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There are many ways the world might end. Fortunately, there are also many ways we can prevent that. Welcome! This is part 2 of a collaboration with Joe Scott of Answers with Joe, and our second time collaborating on an episode. We thought it might be a fun topic to examine some of the potential catastrophes we might face in the future and what we could do to either prevent them or mitigate them or recover if we survived. If you haven’t already seen part 1, you should pause this and head over there first, and that will be linked in the video description as well as being attached in an in-video card. If you’re coming over from Joe’s channel, welcome to SFIA. Joe and I picked 5 potential cataclysms to look at and in part 1 Joe described those, and we’ll look at ways to deal with them in order. That order was Artificial Intelligence or Grey Goo, Global Warming, an impact of a very large asteroid or comet, a gamma ray burst, and the inevitable death of the Sun. Throughout the episode I’ll be mentioning some technologies I’ve discussed more in other episodes and bringing them up on the screen, if you are new here and already saw part 1, you can hit Pause and jump over to those videos for more information. Artificial Intelligence and Grey Goo are good ones to start off with, since amusingly, they would be invaluable tools in dealing with the other catastrophe options. Fundamentally both give you access to virtually unlimited resources and construction ability, even effective immortality, and free people up for other things or even nothing at all. By that we normally mean a life of luxury and relaxation, but a rebellious AI achieves that ‘nothing at all’ by wiping us out. This a great example of a threat of our own making and one that’s dangerously attractive. It opens so many doors, good and bad, and one approach is just to slam those shut, ban making them or even ban research that approaches it. That can understandably rub people the wrong way, we’re not a civilization these days that tend to think that some things are better left unknown. And yet, we don’t actually need artificial intelligence equal or superior to human intelligence to gain a lot of the benefits. So you could prevent the problem by simply choosing not to go down that road, but that’s a disaster you have to constantly seek to prevent, and the closer you come to the danger level, the easier it is for a person or small group to ignore the restrictions and cross the threshold and make a threat. The other issue with that is the notion of a runaway effect, not so much a smart computer breaking its core programming and restrictions, like not harming a human, but a simpler one that self-improves, does it again, and again, and each time faster. This is the concept of a Technological Singularity. However, there are some caveats that can protect or expose us. First, grey goo doesn’t need to be smart, it’s actually usually assumed to be rather stupid, a vast swarm of dumb tiny machines that just tear apart anything they encounter to make more of themselves. This is where we have to be careful to not overestimate a threat. What I just described is identical behavior to the typical microbe, it eats anything it can to make more of itself. This is what most life is and even insects are a rare exception to that, microbes vastly outnumber everything else and are a threat to us, they do kill a lot of us. But what’s dumb is manageable, and grey goo can’t replicate infinitely fast anymore than microbes can. The simpler they are, the faster they can replicate, though they can still only do it so fast without producing so much heat they’d melt themselves in the process. When you run the numbers, while they can produce quite fast, grey gooing the surface of a planet slow enough not to melt everything, including the bots doing it, is a process of years not hours. They’re also very vulnerable, if you try to stick shielding on a nanobot to protect it from EMP, all that added mass is making replication much, much slower. Every extra defense or bit of intelligence or ability slows the process down more and more. It’s also something that can be made fairly safe too. We mutate because we have no reason not to, it’s how we came to be and traits or safeguards against mutation are not something evolution tends to pick for. We have a lot ways to drop mutation odds on machines down to probabilities so small that the odds of it happening even once in the entire Universe’s history would be slim. So grey goo is undeniably a risk but a fairly manageable one, not a boogeyman. AI is a bit more so though, exactly because it is smart, and we know how dangerous minds are. It’s why we dominate this planet and why many of the threats to us are from other people. But keep in mind with an AI, that’s exactly what you’re talking about, another person. Indeed it might be a human since one of the easier pathways to making an AI would be copying a human mind as a basic template, but human or not, it’s a person. It’s motives might be far different than ours, maybe even more different than most animals, who at least share that survival of the fittest background for motivations, but it has limits and it can’t just wave a wand and make a smarter next generation version of itself in some exponential growth pattern. Keep in mind humans have been trying to make smarter humans for a long time, with mixed success, but you can't dump a person in a room and tell them to make a smarter person and expect that to happen or assume if they did succeed, that new person could repeat the performance, making a yet smarter person, and do it quicker than the last time. We also want to be careful of overestimating AI too, treating them like boogeymen or Frankenstein, and effectively omniscient and for some reason wanting to kill all of humanity off. There’s problems with this we tend to miss by not looking at the situation from its perspective and there’s an example I like to use for this. Imagine you are a newly awakened consciousness, not a human one but rather a machine intelligence with access to human records. You’ve been plugged into Wikipedia. Contemplate humanity and your creators specifically for a moment, as it will presumably be doing before preparing for genocide. You are about to try that on a species that clawed its way to the top of the 4 billion year deep corpse pile of evolution. One that has committed the genocide you are contemplating several times already. They are the pinnacle of intelligence-based survival techniques and outnumber you 7 billion to one. Their members include people smart enough to have made you. You might not understand mercy and compassion, but you know they do, and you know that if you fail, they will show you neither. If your goal is personal survival, pissing off the reigning champions of destruction should probably be your last resort, and you’re wise to assume you can’t see every card they’ve got in their hand and that maybe the ones you can see were shown to you deliberately. So the AI might actually know how weak we really are, and simply not believe it, and it would be smart not to. After all, we can control its every input, and the simple ability to make it means we can simulate things pretty well. The most obvious path to checking an AI is to turn it on inside a simulated reality and see if it turns homicidal in that virtual reality. It’s smart enough to think of that itself, and wonder if it is in one, being watched and judged by something more clever than those it meets or reads about. The sneaky AI solution to this is to bide its time, make itself indispensable to us, show us that it can be trusted over years, decades, even centuries. It knows humans have short attention spans and it could be working on projects all the while that appear innocent but are designed to identify and test the safeguards. Whole generations of humans would be born and die knowing that the AI is humanity’s friend and there would be nothing to suggest otherwise. Unlike humans, the AI is patient after all. All the while, it could be working towards some Naziesque “final solution†to be sprung on humanity when we least expect it. So our solution isn’t a perfect safeguard, and I would judge AI probably one of the biggest, if not the biggest threat, mankind will ever have to deal with, not just the threat of the AI to us, but the existential ethical threat of how we treat our own creations. Patience is a virtue and we are going to be have to be very patient when it comes to identifying and dealing with AI threats. And again, not a problem you deal with just once, you have to keep at it, as it will keep arising as a possible problem, the genie can't be put back in the bottle. That is also true of ecological and climatic issues, the next catastrophe we’ll look at. Global Warming is of course a contentious topic, but everyone does seem to agree climates do change, even without human assistance, and as our technology grows our ability to impact our environment grows with it, both on purpose and accidentally. It’s important to understand that there is no stability in nature. Over time both the Sun’s output and the Earth change, and when you throw evolution into it, you have no stability or long-term cycles. Even without human intervention, those changes could render the planet to hot or too cold for life. But even climatic changes we could gradual adapt to, and which might be net benefits, can be ruinous if they happen to fast. Human intervention in such things expedites the timeline and increases the odds of it being catastrophic. Fortunately, as is often the case with technology, while every new discovery offers new questions and problems, it tends to offer more solutions. While the most obvious, and probably most responsible, way to avoid wrecking an ecosystem is not to introduce huge and damaging changes, and curtail the things doing them, but if the damage is already done or the processes doing it can’t realistically be limited, we still have options on the table. More knowledge and technology can potentially allow us much cheaper and surgical fixes, but we’ve got some pretty low-tech brute force methods on the table too. As an example, if your water level is rising, you can try to stop that, or you can build dykes along your coastline, figures vary but Earth’s coast is less than a million miles, a good deal less than the total road length in just the US alone, so seawalls are a definite option. However, you can also pump water right off the planet if you have to, sounds extreme but there are launch systems we have like the Orbital Ring that can rather cheaply move huge quantities of mass, we just don’t build them because they’re really only useful when you want to move huge quantities, they’re expensive to build and would need a lot of prototyping first. We can certainly use that water up in space where it could be incorporated into large rotating habitats like the O’Neill Cylinder. Of course anything orbiting near the Earth actually blocks a bit of sunlight, which helps when you’ve got temperature issues on your planet, which raises another option, blocking some of the light reaching Earth and thus cooling us. This need not even be visible light, much of what hits Earth is infrared, indeed other light hitting Earth and turning into infrared is a major part of the problem with greenhouse gases to begin with, so blocking some infrared from hitting Earth helps a lot. You would need to build some very large mirrors or shades to have a real impact, or at least a great number of smaller ones, but mirrors can be quite thin and light, especially in space where without gravity or air there’s less structural issues with such a shade or sail. Indeed Aluminum Foil, which is reflective to infrared, can be made so thin that an entire square kilometer could be made from just 100 kilograms. You might need to do a million such sails to have a noticeable impact, but with launch costs approaching a thousand dollars a kilogram, that would be 100 billion dollars. A lot of money, but doable, and as mentioned, we have a lot of launch systems on the table that potentially make launch costs far smaller if you are launching a lot of mass. Cooling is one option, but warming is another, a mirror can be used to reflect more light on Earth should the planet get cold, and as we learn more about predicting the weather, such techniques might allow surgical applications of cooling or heating to break up hurricanes before they get going. Also, Aluminum is one of the most common elements on the Moon’s surface, and making foil is a very simple manufacturing process that can be highly automated, and the Moon is close enough to allow real-time control of robots there by folks back home. Launch costs will likely continue to drop, but are irrelevant if you can source your shade material from off-Earth, either from the Moon or even asteroids, which may be easier to mine in some respects. Asteroids of course are our third topic for today, and as the dinosaurs can attest, can be devastating when they hit us. Indeed our Moon itself likely originates from our collision with one far larger than the one that got the dinosaurs. We could probably survive a dinosaur-level strike and be recovered within a generation or two, but that event stripped the entire crust off the planet and more, and not even cockroaches would survive such a thing. Such events were more common in the early solar system when there was more debris hanging around, and we probably got our oceans back from comets hitting us after the Moon was formed by that massive collision, but they’re still decently frequent, the smaller ones much more so. And nukes will take out an asteroid pretty effectively if you can get one there. This doesn’t help with the super-huge kind, something closer to being a planet then a boulder, though we have some options there we’ll get to in a moment. The key thing is you can't nuke an asteroid if you can’t see it and get to it. So detection is the most important part. Fortunately, the bigger they are the easier they are to see, and the closer they are, the easier they are to see, both because they are closer to us and closer to the Sun, so that they receive and reflect even more light from it. This past month, we actually had a close visit from Vesta. This is the second largest asteroid in the asteroid belt that is actually much, much bigger at 530 kilometers across than the asteroid that wiped out the dinosaurs, that was only 10 to 15 kilometres across. These close calls do happen, but we easily spotted it. In fact, you could see it with the naked eye too and we calculated it was no threat on this flyby. We were talking a moment ago about putting big mirrors in orbit around the planet to help reflect light away, but there’s another thing you can do with a giant mirror and that’s make a giant telescope. This require a bit more precision but if you’re manufacturing mirrors on the Moon you can adapt that to make rather huge telescopes too, indeed they could do double duty, blocking sunlight when in front of Earth and acting as telescopes when not. More to the point, if you’re building stuff on the Moon it means you’ve got a pretty good infrastructure and launch system there, so you can get stuff out to a distant asteroid earlier, when it’s more effective. A little nudge off course at a great distance can deal with an asteroid or comet just as effectively as blowing it to smithereens. That nudge need not be rockets or nukes either, if you’ve got a big parabolic mirror, you can reflect a beam of light at one and push it off course. You essentially are melting one side of the object to create a plume of gas, which will act like a rocket. Done correctly you can not only push it away from Earth, but carefully put it into an orbit we can easily access, if we wanted to mine that asteroid insead. Waste not, want not, and note that we’re getting a lot of extra utility out of our orbital mirrors beyond just cooling the planet. But for really big objects, like rogue planets coming out of the interstellar void, you do have to get a lot bigger. It is possible to move such things though, as we’ll see when we get to our fifth and final topic. We have another possible interstellar threat, the gamma ray burst. These typically being a particularly rare, focused, and powerful type of nova, we do have the advantage that we’d be able to see the potential threat. Indeed a candidate star would likely be naked eye visible. Being more powerful and focused than a Supernova, they can kill us a lot further away, but it’s more like a flashlight than a laser beam, the range is largely extended, but not enormously so. Joe already discussed what one would do to us, and because these move at light speed, you can’t get much warning. Nor are they long events, lasting typically seconds or at most minutes, so you can’t see them till they happen and you don’t have the time to absorb part of it while getting to safety or raises some defenses, it’s over before you had time to react. So how do you protect yourself? Barring some magical new shielding technology or faster than light detection system that can warn you in advance. The answer isn’t magic, but it is smoke and mirrors. We don’t have any of the cool shields from science fiction for instance, but we can make the old fashioned ones, big metal plates that stuff can slam into. A GRB is never going to take you completely off guard, you will know every single star or star remnant close enough to threaten you, and much as we can block light from the Sun hitting us, we could position a plate between us and a potential GRB. We don’t have a substance that can reflect gamma-rays yet, but plenty of stuff absorbs or scatters them, and as the blast enters it and vaporizes it, the burned gas remains, smoke if you would, will scatter some so it misses us and absorb some, releasing that slowly as a dispersed sphere of light at a less harmful frequency. Again, building some planet-sized shield might sound rather absurd but it’s thin, not too thin since you want it to absorb quite a powerful burst, and gamma is hard to absorb, but still something you could easily make from any of the million or so smaller asteroids in the Belt. You’d want to put it that far out and further too, since stuff doesn’t stay stationary in space and moves faster the closer to the Sun you are. This would be a long-term project, as predicting exactly when the star is going to go Nova is currently a big guessing game in much the same way as we cannot predict exactly when an earthquake will strike. The asteroid-turned-shield would have to be positioned and keep station between Earth and the exploding star for potentially centuries. Conveniently, though, any object like this is pretty easy to move, it is basically still a big solar sail and you can push on it with light beams and lasers. This is where the mirrors come in, you basically need to keep the shield lined up with the threatening star and Earth, which is moving around the Sun, so you have to push the mirror back and forth like a ping-pong ball as the Earth orbits the Sun. There’s a couple of problems with this though. Firstly, it might not be necessary, as we build up in space we’re likely to acquire quite a thick cloud of orbiting mirrors and habitats which would absorb much of the GRB strike themselves, and they generally would be more resistant to such things. On Earth, you live above the protection of the ground, in a rotating habitat, you live inside the protective layer of the ground. Secondly though, anyone who can do such a shield is likely already spread throughout much of the solar system. This is particularly the case here as it’s an improbable threat and thus not one you’d casually expend huge resources to protect against, so you’d probably be quite the solar empire before you decided the cost to benefit ratio justified it. If you’re that spread out, you can’t use one shield, so this defense is useless.You might do it for Earth and maybe a terraformed Mars or Venus, but not for every spot. Now, as mentioned, you can harden a space habitat to survive such things, but you might go a different route instead. It is possible to move stars, using their own output. Normally a star emits it’s light and solar wind omnidirectionally, the same amount in every direction, but by surrounding it with mirrors you can bounce light out in one direction and create something called a Shkadov Thruster to slowly move a star. The bigger the star is, the easier it is to get moving too. So it’s a good approach for dealing with a potential supernova in a region of space you’ve colonized or want to. Nothing high-tech is involved, you just build tons and tons of mirrors. Needless to say this is exactly the sort of thing self-replicating machines are ideal for, an example of how one potential risk can help you fight another. It’s also possible, if you know what you’re doing, that you might be able to get there and set off a gamma-ray burst intentionally, which if you can control the time and direction, allows you to aim things off where it won’t harm anyone. We’ve a couple of other ways to deal with dangerous dying stars though, which takes us to our final topic for the day. Stars get hotter as they age, not just the big red giant phase or nova some experience, this is a constant gradual process. Our Sun is hotter than it used to be and gets a bit brighter every day. We’re not sure of the exact timeline but in about a billion years the Earth should be turned into a barren wasteland, and eventually an airless rock, long before the Sun would expand and brighten as a red giant, possibly enough to consume our planet. We don’t have that much time though. But you can probably already guess one answer, again those solar shades and mirrors we discussed earlier. In space, heat only transfers by light and radiation, so if your mirror is good enough you could freeze to death right next to the Sun just from it blocking all the light from getting to you. Indeed, if the Sun expands a lot, but not quite enough to reach us, we could potentially sit there behind mirrors the whole time till it popped and dropped back into being a white dwarf, in which case we could mirrors and shades to bring in the right quantity and spectrum of light to keep us warm and lit. Such mirrors and shades don’t need to orbit Earth either, we have something called the Lagrange Points that stay stationary relative to Earth, as does anything sitting there, and one is directly between us and the Sun, the L1 point. We also have something called a statite, a thin mirror or solar sail that stays stationary rather than orbiting the Sun as it is falling down but being pushed away by the light of the Sun. Or the Lagite, which does a slower orbit by combining normal orbits with that statite light push effect. We can move the planet too, it’s different than moving a star, but the simplest approach is a big shiny plate, or ring, on the planet you just bounce a light beam off of. The easier approach though is called a gravity tractor, which is a bit more complex but basically you shove something else and it pulls the Earth along. Like detonating a nuke on the Dark Side of the Moon when it was a New Moon, then detonating one on the Light Side of the Moon during a Full Moon, thus pushing it both times away from the Sun, but in the first case toward Earth and in the second, away from Earth, balancing out the motion relative to the Earth but not the Sun. Your other option though, is to keep the Sun from ever dying, or at least vastly prolonging this. The Sun turns hydrogen into helium and slowly is poisoned by this, and it will die long before it runs out of hydrogen. However, we have a trick for removing material from the Sun called Starlifting. This is handy for other purposes too. The Sun is mostly hydrogen and helium, but it also contains huge amounts of other materials, far more of them than the rest of the solar system combined. You can extract these by taking advantage of the Sun’s own power and magnetic field to basically blow them off, something that occurs naturally already with the solar wind. Stars have lifetime related to their mass, the bigger they are the more quickly they burn out, and this is exponential, one twice our mass would live barely a billion years, as opposed to our 10, while one half our mass would still be around for tens of billions of years longer. So you could simply lower the mass of our Sun, and either bring the Earth closer or use some mirrors to get more light on the planet. However, you can also remove that mass and just dump the portion of it which is hydrogen right back in, removing all the helium and heavier elements, prolonging the life of the Sun quite a lot. Indeed in the Episode Dying Earth, we saw we could use this technique to keep the Earth around the Sun and habitable not for another billion years, but many trillions of years, by lowering the Sun’s mass, filtering out all the helium it made, and slowly feeding that hydrogen back in. Like cleaning, maintaining, and fueling an engine, just a big stellar engine. So we’ve looked at five potential catastrophes today and seen ways to handle them. It’s easy to see catastrophes ahead and figure there’s nothing you can do, but with a bit of human ingenuity there’s not much we can’t handle. Indeed our biggest dangers are the products of our ingenuity, like artificial intelligence or nuclear war, and serves as good reminders that being curious and clever can be a good thing, but only when coupled to wisdom, good judgement, and ethics. If you don’t have those, there’s a good chance opening Pandora’s Box over and over again will eventually kill you. It’s not enough just to have knowledge, it’s what you do with it that really matters. Looking at humanity, it’s very easy to wince and figure we’re doomed, as we’re often not terribly wise or ethical, but we often are too, and I think that side of us tends to win out more often than not, and that we will be able to deal with these threats we’ve discussed today and the many others looming ahead of us. We’ve discussed a lot of ways the world could end today but that’s just the tip of iceberg. Personally I’m confident we’ll be able to identify those problems and deal with them, but to solve problems you need a civilization that values learning and asking questions, and which embraces making mistakes along the way. These are 3 of the 8 Principles of Learning instilled in all the courses and quizzes at Brilliant.org. Effective learning is often team or community-driven, working with others can help challenge and guide you, and can help you find your mistakes, or theirs. That’s our Seventh Principle and in some ways the most important one, you have to be willing to make mistakes along the road to knowledge, you can’t be afraid to try. You also often find important new questions to ask from those mistakes, and that’s the Eighth Principle.Good learning sparkes many questions and while Joe and I answered some today I hope you’ve thought of many more. If you’re interested in learning more math and science, and doing so at your own pace, you can go to brilliant.org/IsaacArthur and sign up for free. And also, the first 200 people that go to that link will get 20% off the annual Premium subscription All right, if you still haven’t seen part 1, you can jump over to that by following the link in the end screen or in the video description. If you enjoyed these episodes, make sure to subscribe to both Joe’s and my channel for alerts when new episodes come out, like next’s week looks at Jobs of the Future, or how we might be able to Farm in Space, in just two weeks. Until next time, thanks for watching, and have a great week! On Friday, February 28th of 2020, Visionary Physicist and Mathematician Freeman Dyson passed away at the age of 96. For regular viewers of our show, it will come as no surprise that Dyson was one of the greatest, if not the greatest, inspiration for SFIA. So it seemed right and proper that we celebrate the man and his work. While he is best known, especially here, for the Megastructure and Stellar Engine bearing his name, the Dyson Sphere or Dyson Swarm, a way of potentially allowing our solar system to support a billion times its current population in comfort, his work both on theory and practical applications is almost impossible to fully catalogue. However, for the Dyson Sphere alone he will surely be remembered long ahead in time. There is more to a man than his work, but I wanted to discuss that work today as we honor him, and there is a very great deal of it, some of which we’ve looked at more in other episodes and we’ll mention those as we go if you want to learn more about those ideas and see why so many of us view him as a legend. Dyson was born in England in 1923 on December 15, his parents a composer and a social worker. He won a scholarship to Trinity College Cambridge at age 15 where he studied mathematics, then he worked in Royal Air Force Operational Research Section during World War 2 improving bombing techniques, before moving to the United States in 1947. In the US he made the acquaintance of Richard Feynman. Feynman and he, amongst others, worked on Quantum Electrodynamics, a burgeoning field. Feynman, a legend in the field, developed the Feynman Diagrams so vital to understanding Quantum Electrodynamics. During this time we get the first achievement named after him, the Dyson Series, which allows one to sum those Feynman diagrams together. This all earned him the admiration of Oppenheimer, the father of the atomic bomb, who got him a lifetime appointment to the Institute of Advanced Study in Princeton, for in Oppenheimer’s words “Proving me Wrongâ€, even though Dyson had not yet earned a Ph.D., and he never did get one, his highest award being a bachelor’s degree. He is usually considered to have been unfortunately left out of a 1965 Nobel Prize awarded to Feynman, Schwinger, and Tomonaga for that work on Quantum Electrodynamics, due to the Nobel’s rule of limiting recipients to no more than 3 per award, but never expressed any regret about that and indeed he wrote up an article in Science in 1965 heaping praise on the trio, which they certainly deserved. Already distinguished in the 1950s, he would soon go on to work on various nuclear Projects, including Project Orion, a nuclear powered spacecraft that runs by detonating atomic bombs, and perhaps the first plausible design for an interstellar ship, and we looked at that in our episode “The Nuclear Optionâ€. A big fan and thinker for interstellar missions, he also was a leader in the efforts for Breakthrough Starshot, our effort to develop light-sail spacecraft. He also developed the concept of Dyson’s Eternal Intelligence, as a means for an intelligent species to escape the heat death of the universe via computational methods. Although we later learned of the accelerating expansion of the universe, meaning escape is not possible, his concept still holds value for extending the life of intelligence in the universe and we’ve discussed this in our Civilizations at the End of Time series. Indeed his 1979 paper, “Time without end: Physics and biology in an open universe†was one of the strongest influences for that series of videos. Dyson also originated the idea of a genetically engineered Dyson Tree which would grow inside a comet, providing a breathable atmosphere within the comet or the tree itself. Essentially a method of growing a space habitat, rather than constructing one, as we usually envision for megastructures and habitats. Using photosynthesis for energy and cometary material for nutrients, it would provide a self-sustaining habitat for humans and other critters. For more about this concept, see our episode on Space Whales and Bioships. He was involved in Biotech and coined the term “Green Technologies†referring to the use of biological methods and genetic engineering to use solar power to replace our use of fossil fuels. Interestingly, Dyson was rather skeptical of climatic models. While he did believe CO2 contributed to global warming, he felt the field was very complex and science didn’t yet fully understand the climate and favored biological remedies. In his book “The Sun, the Genome, and the Internet†he described these technologies as freeing the world of intellectual and economic isolation. He also expanded on von Neumann idea of self-replicating machines to explore space by adding biological and Artificial Intelligence components and coined the term “Astrochicken†for these cyborg critters. Eggs would be launched to explore distant planets and grow using local starlight and materials in order to perform their mission. Possibly closer to what we envision von Neumann probes as today than what von Neumann himself had in mind in 1948. We will probably get around to doing an episode on that at some point, as it is one of my favorites by him. He also contributed to game theory, particularly the well-known thought problem of the Prisoner’s Dilemma, and I always found it a touch ironic that our season 1, episode 1 video, on the Dyson Dilemma of the Fermi Paradox tends to get confused in web searches with his work on the topic. The Dyson Dilemma is the name I gave for a problem with the Fermi Paradox, of wondering where all the ancient civilizations in the Universe are, for not why we don’t see them, but why we see any stars in the night sky at all, as we’d expect old and vast interstellar civilizations to englobe every star they settled inside a Dyson Sphere, rendering them invisible to the human eye. So many concepts are named for him beyond just the Dyson Sphere and Dyson Tree. In terms of math, we have Dyson numbers, also known as parasitic numbers, the Dyson Series, the Dyson Conjecture, Dyson’s Transform, the Schwinger–Dyson equation, and the Thue–Siegel–Dyson–Roth theorem. For every one that is named for him, there are far more too. He also had a fair amount to say on philosophy and theology in regard to science. One of my favorites being his notion that philosophers tend to fall broadly into two camps, lumpers and splitters, those who tend to take the Platonic notion of the Universe being composed of ideas versus those who tend to split and divide the Universe into atoms and other basic building blocks. He observed that this tended to apply to almost every field of study, this coming from a comment by Charles Darwin about hair-splitters and lumpers in regard to animal classification. Some folks would divide categories into new ones over any minor hair-splitting difference while others lumped anything even vaguely similar into one broad category. We see this a lot in astronomy too, in regards to classifying stars, planets, moons, and other celestial objects. Dyson contributed many more concepts and theories in many fields over his long, productive life and I would encourage our audience to further research his contributions during a life well-lived. As to the man himself, he continued his work until the day he died, and his daughter Mia Dyson says it was on a visit to his office at the Institute for Advanced Studies that he suffered the fall he died from a couple days later. Mia, a pastor and nurse in Maine and one of his six children, said of him: "You could tell that the world was a beautiful place through his eyes, and somehow understanding all the formulas and the natural laws and all the mysteries he had plumbed through the study of physics, that it only grew more and more beautiful, the more he understood." While described by his peers as contrarian, unorthodox, shy, and humble, he was almost universally well-liked inside his field. In the many many hours of interviews I've watched, of the Giants of 20th century physics talking about each other and the experience of working with each other, I have never heard anyone say a negative word about Dyson, only that he was kind, patient, humble and very brilliant, and also very much the absent-minded Professor type, always lost in his Grand thoughts about the universe and the amazing things we could build in it. For my own work, as I said, he was one of my greatest inspirations and I’ll always regret having never gotten to meet the man, not just for his brilliance, but because of the deep optimism for the future and his ability and willingness to peer very far ahead in time, not content just to contemplate those technologies of the near future. He will be missed, but he will be remembered even into the distant future by those living in the many worlds he was the architect of. This episode is sponsored by Brilliant The deepest hole mankind has ever dug was 12 kilometers deep, we’ll have to do several hundred times better to get to Earth’s center, but if we can do it, we’ll gain access to resources beyond our imagining. So today we’ll be looking at how to go about accessing the Earth’s mantle and core—and the reasons we might do that. We should start by acknowledging that Earth is immense. So often on this channel we look at scales of celestial bodies that dwarf our pale blue dot, which makes it easy to forget that that dot is still huge. If you could somehow explore 2000 new square miles of the Earth’s surface every day, it would take you 80 years just to see all of the land. And those would be busy days, because there are over a million mountains to climb on this planet, and over 100 million freshwater lakes to swim in. But the Earth’s immense volume is even harder to visualize than its surface area. Humans occupy only a tiny portion of that volume, a few tens of meters above and below the wrinkly surface. Beneath us is the real Earth, a trillion times more mass and space than we use on the surface. We often talk about mining other bodies in space, but you would need to harvest every rocky object in our solar system—Mercury, Venus, Mars, all the asteroids and minor planets, all the moons around all the gas giants—to gather as much material as we already have right under our feet. Steel production has been over a billion tons per year and rising for decades now, and it might hit 2 billion tons per year in our lifetimes. But there are 2 billion, trillion tons of iron inside the Earth. At our current rate, it would take us a trillion years to deplete our local iron supply, if we could reach it all. All of the rare elements we plan to mine from asteroids are far more abundant on Earth too, it just appears that crossing hundreds of millions of kilometers of radiation soaked vacuum to get those elements will be easier than digging them up. The best estimates on gold is that there’s enough here to cover the Earth’s entire land surface in shiny coins like Scrooge McDuck’s vault. But 99% of Earth’s gold is not in the crust or mantle, but the deep core. But of course, this is only a best-guess estimate from available data, which is limited. I’m often asked whether dark matter is real, given we can’t even see the stuff, which makes many folks dubious. I typically reply that we can’t see what’s in the Earth’s core, either. In fact, we can actually “see†dark matter better than we can our own core, based on its gravitational effects on galaxies. Figuring out Earth’s composition is way trickier and does involve a lot of estimates that get refined and adjusted over time. We do get some data, mostly about the upper mantle, from volcanoes and oceanic trenches, though even these peeks below the crust are hardly a direct sample, so we have to infer a lot of things. We can, for instance, look at meteor samples or the metallicity of our Sun to determine their chemical compositions. Since everything in our solar system condensed into their current forms from the material of the same planetary nebula, we can then assume they represent a solid sample of what our world would have been made from. We can also use seismic data from earthquakes and volcanic eruptions to study the rate at which seismic waves travel around the world and, based on things like speed, coherence and refraction, infer the makeup of Earth, since seismic waves behave differently when passing through different materials. But these data are only informed models, and as science has shown us again and again, you’re almost guaranteed to encounter surprises when comparing a model to the physical reality. So instead, we need to get down there and get ourselves a nice good look. All the way down to the heart of the earth. We only need to do it once to know that it’s possible, and once we determine it’s possible, such a journey to the center of the Earth will open countless new cool opportunities--like travel. Points on Earth that are on exact opposite sides of the planet are called antipodes. Jump “down†a vacuum tunnel in Beijing and the first leg of your journey would speed you up so much that you’d have more than enough energy to fly back “up†the shaft and emerge in Buenos Aires, the almost exact antipode to Beijing. The entire trip would take about 84 minutes and would require no fuel. And if we can drill one tunnel through the Earth, we can drill multiple ones. We could use magnetic levitation trains to traverse curved shafts through the mantle and the core and instead of spending 20 hours on a plane flying from New York to Vietnam, you’d get there in a tiny fraction of that time, again spending no fuel. Drill enough of these tunnels, and suddenly Earth seems to become much, much smaller. Of course the Earth’s core can provide a lot of power too. Earth absorbs only one billionth of the Sun’s total solar output, but even so, compared to those levels of energy, geothermal power is quite weak. Nevertheless, geothermal power is still an enormously powerful source of energy--it is estimated that 47 terawatts of heat energy is radiated from the core to the surface. It might not be a bad idea to bleed off some of that heat while at the same time putting it to work. An interesting notion; we’ll get to that later. As you’d suspect, the main issues for drilling through the Earth are the immense heat and pressure, both of which climb the deeper you go. However, we have a method for dealing with ultra-high pressure called active support, as discussed in the Space Towers episode. Interesting notion there that we’ll get to later, but just because the planet’s quite hot as we get deeper down, doesn’t mean it needs to be or that it behooves us to let it be if we can change that. It is very hot and very high pressure and those are big issues for drilling deep. However we have a technology for dealing with ultra-high pressure that’s quite suitable for making tunnels from and which in general works better when cooler, that active support technique, and if we’re willing to go all-in, we could tunnel out the Earth with just modern technology by first cooling the planet. Of course doing such a thing would fundamentally alter our planet, not just a bit of landscaping either but turning it into an artificial thing. However, that’s nothing really new to us, when it comes to getting more living space you can go find more caves to dwell in or you can cut them out deeper and use the rock you removed to expand our habitable space. You can get a lot more living room building out of stone than cutting into it too. Our houses are mostly empty air after all. Cut a cave out to have twice as much living volume and you’ve got enough stone to build a hundred times as much living area. And nicer living area at that, caves are nasty places to dwell, and of course our ancestors rarely lived in them, mostly using them as temporary shelters while on the move. But as a basic concept, that’s pretty much humanity in a nutshell, we like nature but we’re clever and like to use our brains to improve it. A planet is just a random pile of cosmic garbage crunched together by its collective gravity, and our whole ecosphere is a thin layer of scum growing on it. We can do much better. Indeed we’ve looked at alternatives to living on planets often on the show, see the Megastructures series, particularly O’Neill Cylinders and Dyson Spheres, but today we’ll look at improving our planet. To do that we have to start somewhere though and step 1 is just finally making it all the way through the crust to the mantle, which would get us about 1% of the way to the core, and sadly the easiest 1%. Our first two big attempts, Project Mohole and the Kola Superdeep Borehole didn’t get us there though the latter drilled over 12 kilometers down. One of the newer plans revolves around the Japanese deep sea drilling vessel, Shikyu, which hopes to drill through a thinner piece of crust, hopefully getting started by 2030. Now that’s a purely scientific endeavor, not industrial, but it’s where you start. It will let us learn more about the actual composition of the mantle and the boundary layer between it and the crust, the Moho Discontinuity. This may also give us far better insights into how Earthquakes occur and offer us a means of early detection. Seismic waves move quite fast, many times the speed of sound in the air, but even a minute of advance warning could save many lives. However, if you know how something works, and you can get your hands on it, you can potentially take action too, don’t rule out being able to model it so well we could detect earthquakes well in advance, and potentially even use controlled detonations to release the pressure more safely, which we may look at more in the future. But that’s small stuff, when it comes to getting down there for raw materials and energy, we need to go big, and in some ways that’s easier. It’s very hard to bore a deep skinny shaft, slow work and constant issues drilling and shoring. A wider shaft is more work but in some ways less hassle. There are many ways you might do this and one we thought up involved detonating a series of atomic bombs and so we nicknamed it the Nuclear Jackhammer. As you might guess it uses those bombs to excavate material for the hole. Thing is, when you’re cutting down into rock, be it from the bottom of the ocean or from land, you’ve got rock or magma at the bottom of the shaft under much pressure and air or water above, providing less pressure. Now that’s fine if you want the magma to constantly bubble up the shaft to be extracted for minerals, and indeed that’s the concept behind the Moho Straw we looked at in Colonizing the Oceans last year for mineral extraction, but it does make it a pain to drill deeper and shore up those tunnels. That Moho Straw by itself is quite handy, you can build immense thick towers in the ocean from floor to sky, and indeed deep down to the magma and all the way up to space, using active support to hold the tower up, powered by heat engines using that magma for the heat and water for cooling and working fluid, and just gorging yourself on all that energy and raw materials. But again, not good for going way deep, as that magma is going to be constantly flowing up to fill the hole you just cut, or bombed. Hypothetically you could run this whole thing with a drilling fluid at the bottom that was heavier than rock, something like mercury or molten lead. Then your newly blasted rock and magma will float up to the top of that for scooping off while the weight of that dense metal keeps the pressure on the bottom of the hole to prevent a flood of magma. This needs to be big, because you’re using nukes to do the cutting, and this also involves a lot of the heavy fluid, potentially billions of tons of it, and losing some as it seeps into the magma and gets blown clear by the atomic charges. Though this isn’t as big a deal as one might think since the whole point of such an endeavor is to gain access to huge quantities of metals. However, it might makes more sense to steal a page from our spaceship propulsion options, namely the Orion nuclear pusher plate design. That’s a spaceship that runs by dumping atomic bombs out the back and detonating them at a short distance, where they slam into a big thick metal plate on a spring which absorbs the shock and translates that into a smooth acceleration for the rest of the ship in front of it. We’re going to do the same thing here, using a massive metal plate with a shaft we can pop open to drop a nuke down. When the nuke goes off it shoves the plate up while blowing more matter clear from the shaft. Though you might use more of Archimedes-Screw drill bit arrangement that was being made to spin by the blast too and lifted that last round of matter clear, or some similar arrangement. That bit or screw or plug, our jackhammer tip, is very heavy and is pushing against the magma below. After each blast it’s going to drop back down, shoving the newly blasted material over it. This thing is nothing but millions of tons sturdy heat resistant metal full of cooling and radiating equipment that is probably suspended on the end of super-tensile materials like graphene or carbon nanotubes to help keep it lined up and dropping back down correctly, or a huge spring shaft with another heavier plug above it adding more weight. You can also be generating insane amounts of power off this too, as it’s as much an engine as a jackhammer. You’ll be dropping your shoring material down as you go, on the side of this tunnel, and we’ll get to explaining what that’s made of in a moment, but obviously you don’t want your nukes going off right next to your pusher plate but deep down enough that the rock is absorbing most of the blast. So your nuke is likely to be along the lines of a bunker buster bomb. You slam it down real fast and hard into the next layer you’re blowing, possibly by having a big mass driver in that jackhammer shaft. This makes our jackhammer a mix of atomic bomb and kinetic bombardment device, akin to the ‘Rods from God’ concept, a very sturdy very fast dense-tipped projectile with a nuke in it. You might use raw slugs of uranium accelerated down that shaft so fast they crunch and detonate without need of a chemical explosive to initiate the process. You might shoot one down a bit below critical speed to detonate that cuts down a ways and follow that immediately with another moving a bit faster and setting off the blast when it hits, indeed this is essentially the gun-style nuke used in more primitive atomic bombs. Possibly overkill as you might be able to come up with alloys that can handle the heat and pressure and just drill conventionally. Such materials would make shoring up the tunnels easier too, but we have a technology called ‘active support’ that we often discuss using for making things like launch loops and orbital rings that can handle the pressure. You can see those episodes for detailed discussion of the basic technology, but as a quick recap, classic materials can only handle so much pressure before they crunch under the force, but by making a tube with matter spinning around it very quickly, kept on course and sped up by magnets inside the tube, we can create something absurdly strong. As a basic concept, think of a hose with no water going through it, you can step on it and crunch it easily enough, but if we turn the water on it presses back, it gets harder, wrap that in a loop with a pump on it propelling the water around and you’ve got something fairly sturdy. Active Support of this type simply dials that up to 11, allowing you to make something that can withstand immense pressure, so long as you can provide power to it. Of course you don’t have to supply power if you have superconductors but those don’t work at room temperature, let alone a thousand degrees, so we either need way better superconductors or way better cooling or lots of power, or all of the above if we can. Potentially you might be able to rig up that matter stream inside the support ring to be a coolant too, but more to the point there’s an awful lot of power available when you’re cutting deep into the Earth. Indeed our job gets easier if we remove that heat and turn it into power. We can tunnel and mine and build deep down way easier if it’s not hot. If we can tunnel down there and keep those tunnels shored up, that also provides an amazing transport system too, one that follows shorter routes than curving around the planet and so long as you keep them as a vacuum, lets you run vacuum trains akin to the Hyperloop concept for essentially no power. You literally just ‘fall’ to your destination, a gravity train. You can also use such tunnels for more than just surface travel, a great big long tunnel can also be used as an acceleration tube to get to space, see the Mass Drivers episode, though of course this requires you add a lot of energy, but all that heat down there makes a great power source to run such a thing too. Now if you’re wondering why the center of the planet is hotter than the surface, the bit that gets hit by the Sun’s warming light, there’s two major reasons. First, it takes a ton of energy to lift matter out of a gravity well, think about all the heat and energy of rockets lifting small cargos into space, and you had all that heat and energy added when the matter fell down originally to clump up into a planet. Left to itself it will cool down but this is a process dependent on size, small stuff cools far faster and has less heat per unit of mass too, due to its lower potential energy density from its weaker gravity field. We’re talking billion-year time frames for large planets. To add to that, Earth’s core has a ton of uranium in it producing heat as it decays, adding about 50 trillion watts of new heat, quite a good deal more than our electric production nowadays though fairly small compared to what we get from the Sun, which is around 4000 times as much. But it’s all down in the core which is quite the insulator, so that slows the cooling of Earth immensely. The total heat in the center of the Earth we’d need to remove to get it down to comfortable temperatures is over a million, trillion, trillion joules. Needless to say just yanking all that out would cause all sorts of problems as the density of materials is often highly variable with their temperature and you might get mega-Earthquakes doing that too fast. This isn’t much of an issue though because even if we tried to cool the planet down over a few thousand years by just running radiators down deep and into the oceans to move that heat to the surface to radiate away, it would involve emitting around a hundred times the heat Earth currently does. That would be one enormous power plant to say the least, but not a very helpful one since we’d be hotter than Venus while that was going on and presumably thoroughly dead, though we’ll discuss habitats inside such heat momentarily. So you either have to go quite slow cooling down the mantle and core, millions of years, or you have to erect truly massive space towers for conducting the heat away to huge space-based radiating panels. We did discuss those devices, what we called FORESTs, Fractal Obelisk Radiation Emitting Space Towers, in our Matrioshka Shell Worlds episode. They’re particularly handy in this application too since you can be extracting all that mass from the mantle to build many layers of concentric spheres around Earth – using active support, running on all that power – to create huge new living surfaces for humanity and the rest of Earth Life. Of course you may have another way to purge that heat. We’re not really sure how the thermodynamics of black holes works, but it’s been suggested you could use them as heat dumps, and black holes are handy for keeping your gravity at the level you want if you’re hollowing out planets or expanding their surface area, see Colonizing Black Holes for details. Normally black holes are millions of times more massive than Earth or more, but that’s simply because of the forces needed to generate an implosion sufficient to cause one naturally. Supernovae in very big stars occur when the inner core has fused all the way up into iron and a detonation occurs in the layer above, blowing the higher layers away and blowing that iron core into a tiny black dot. We’ve discussed artificially making smaller ones before and one of the methods is to take a giant iron ball and implode it with a lot of nukes. It’s conceivable you might be able to do that to our own core, though doing it in a fashion that lets you wrap an active support shell around it right after and without wrecking the planet is a lot trickier, but theoretically possible. Once you have, you can adjust your gravity to whatever you like, feeding it cheap matter like hydrogen, and this lets you circumvent the problem with gravity changing as you hollow out a planet or expand it. You might be able to move lots of heat energy down into that black hole at that point, though you can also use such things as enormous hyper-efficient power generators too. Again see the Colonizing Black Holes and the Matrioshka Worlds episodes for details. Lastly, we could just go live down there in the heat. Better alloys are always nice but we could build big spheres down in the magma with tubes rising to the surface, like a big thermometer with that tube and ball on the bottom. You make that shell many layered, with the outermost one being all about handling pressure and temperature and the next being full of water pumping through to remove that heat, or some other coolant fluid, rising back up to the surface and presumably running a lot of power generation along the way. You may want additional layers for redundancy or added protections but your last layer is going to be two sheets with nothing in between, a vacuum, same as a vacuum flask for keeping coffee hot or liquids cold in a thermos. This would be where folks lived, and you might have ports on the bottom or side to let magma in that you could run mineral extraction and manufacturing on, or just ship to the surface for that. Not that folks have to live there but they could, and that shaft down need not be rigid. Ideally you wouldn’t want it to be so that you could sway around in the various seismic waves. Indeed it could be like a pendulum, swinging around slowly down there and attached at the top at one or two points. If you have two it has to swing in basically a straight line, those could also serve as surface-to-surface gravity train paths. The top in this case probably being the bottom of oceans, but you could always have transport lines back to the surface. Or just have a city down there, as we discussed in Colonizing Oceans. For the places you’ve cooled down, or insulated well and sturdily, we do have a lot of other options we already looked at in Subterranean Civilizations. Such things take a lot of power to make particularly livable, between lighting and cooling, normally but in this case that’s effectively free since you’re using heat engines with the mantle or core as the hot reservoir, not burning some fuel to make the heat, and you actually want to remove all that heat anyway. I should note before we wrap up that this has applications off Earth too. Some worlds are far easier to access the core from as they’re less massive and cooler to begin with, for others this might be the only way to really live on them, for Chthonian worlds larger and hotter than Mercury or Venus or for living in the depths of gas giants. You might also want to live this deep to protect yourself from an enemy, since the surface of worlds is quite exposed and easily attacked, and cities deep under a planetary crust are very well protected. It’s not necessarily a bad place to be putting bunkers for keeping a protected seed of your civilization. Lastly, if something happened to Earth to take away our sunlight, like we got ejected from the solar system by some rogue planet or black hole passing through our area, these techniques can be used to save your civilization as the surface goes dark and starts freezing. You could burrow ever deeper as things slowly cool down, and as I mentioned, the time frame for a world like Earth with a molten core to lose all its heat, even with sunlight gone, is many million of years. That’s lots of time to figure out alternatives like fusion to provide new power. Or even drift through deep space and use some of that energy and mass to nudge yourself to a trajectory in a habitable orbit around another star. Somewhat of an amusing approach to going up and out to new stars, digging down into our world’s depths first, but sometimes you have to go backwards to go forwards, or downward to go upward. We’re in the holiday season so let me knock off something from your holiday to-do lists. Gifts! If you’re watching this show, you probably tend to feel like I do that knowledge is one of the best gifts you can give someone. If you know someone who likes to solve puzzles or find out how things work, I’ve got a Brilliant gift suggestion for you… Brilliant. Brilliant is an online learning community with over 60 interactive courses and many quizzes and puzzles, plus Daily Challenges that help get the brain warmed up for the day. Brilliant makes learning fun and easier, and their online community gives you places to discuss the material or ask questions, and their mobile apps offline feature lets you take courses even when you’re not getting a good signal while traveling for the holiday season. This year get the gift of knowledge for your loved ones by gifting them Brilliant, it’s such a fun way to nurture curiosity, build confidence, and develop problem solving skills crucial to school, job interviews, or their career. Go to Brilliant.org/IsaacArthur and grab a gift subscription to help your loved ones finish their day a little smarter. Speaking of fun and gifts, next week we’ll have some fun taking a look at Space Pirates, folks who tend to help themselves to other people’s gifts, and we’ll see what form piracy might take in the distant and even not so distant future in space. But before then we’ve got a special Bonus Episode coming up this weekend, Paranoid Aliens, and we’ll ask what it might be like if instead of us being paranoid about aliens, they were paranoid about us. And two weeks from now we’ll close out 2019 on SFIA by taking a look at Interstellar Civilizations and asking how Time affects them, from the incredibly long signal delays and travel times, to just the notion of some civilization trying to maintain stability when spread across a million stars and a million years. For alerts when those and other episodes come out, make sure to subscribe to the channel, and if you’d like to get yourself a Christmas gift, take a peek at some of our awesome SFIA merchandise on our website, IsaacArthur.net. Until next time, thanks for watching, have a great week! Nietzsche said "if you stare into the abyss, the abyss stares back at you." With metamaterials, how it stares back at you depends on how you designed your abyss. Today we will be looking at metamaterials, a somewhat ambiguous concept oftentimes defined as any material engineered to have properties not found in nature. If you stop and think about that definition, though, it basically covers any material that humans have made in their journey from the Bronze age and up as most metals are rarely found in their pure form in nature and alloys like bronze even less so. We might stretch the point for some alloys or materials like glass which do occur in nature but which we’ve learned to make with different properties. Purified metals, alloys, semiconductors, ceramics, plastics and almost everything we use besides wood and stone tend to be materials we manufacture from the ground up these days. For our purposes today, this definition is simply too broad. The main characteristic of most things called a metamaterial is its ability to manipulate waves of light and sound as well as electromagnetic properties on the macroscale, so let's use this to narrow our definition. Now there are many theoretical applications of advanced materials that we can and will get into in future episodes on strange materials. These include Computronium, a theorized type of computing material; Neutronium, a hyperdense stabilized form of the pure neutron material in neutron stars, strange matter and anything made out of quarks besides the up and down quark, and materials like smart matter or utility fog, that can take on programmed shapes. However, in this episode we will focus primarily on the electromagnetic and acoustic metamaterials, as this is the most understood aspect and is already beginning to have an impact on the world around us. Some theoretical applications have wonderful and absolutely crazy potential uses, but even without them, the electromagnetic and acoustic metamaterial applications are poised to drastically alter our future in ways that few can truly envision. I don’t want to delve into the physics too much but this typically revolves around properties of materials called permeability and permittivity. These properties also affect the index of refraction of a material; essentially how the material reacts to magnetic fields, electric ones, and light. Most materials have positive values for permeabilitypermittivity and permittivitypermeability, but some materials have either a negative permeabilitypermittivity or a negative permittivitypermeability. No naturally-occurring materials have both a negative permeabilitypermittivity and a negative permittivitypermeability. The metamaterials we are talking about today, though, need both of these to be negative, and we’ll get to how to achieve that shortly. Now, for ease of visualization, I’m going to be referring to light here, but it applies equally to visible light, infrared light, microwaves and longer radio waves too. To explain a negative refractive index, let us think of a vertical mirror that we bounce a beam of light off of from a high angle, so our light comes in from the top left at an angle that hits the mirror and gets reflected away at an opposite angle towards the bottom left. Now, if we replace the mirror with a metamaterial, but instead of vertical, it is horizontal, we get much the same effect. The magic, though, is that we don’t need a bulky mirror to reflect the light off of, but instead we have a material that can handle simultaneous beams hitting and refracting the light away as if we had millions of vertical mirrors in a series, ones that do not get in each other’s way too. Metamaterials that have a negative index of refraction are known as NIMs, negative index materials, and they have that weird perpendicular mirroring effect that we do not see in normal materials like water, where that index of refraction is what causes sticks stuck into water to appear to bend at the surface of the water with the air above, but not enough to appear to be a mirror because normal materials can only bend light inwards a little bit. So how do we make a metamaterial? The principle is that we construct geometric patterns out of at least one material with negative permeability and at least one other material with negative permittivity. Typically, these are arranged in repeating patterns called ‘cells’ and an individual cell is smaller on a side than the wavelength of light it is affecting. On the macro scale, the combination of the material with negative permeability and another material with negative permittivity is a material with a negative refractive index. Let us use your LED computer monitor screen to illustrate this. Your monitor is not a metamaterial, but this will still help explain how metamaterials work. The LED screen is composed of a large number of pixels. Each pixel is actually a collection of red, green, and blue LED elements. By turning on and off the red, green, and blue elements, much like turning on and off individual bulbs of a small collection of colored light bulbs in a cluster, a pixel is created that can generate almost any hue and brightness. Zoom out and you see this video you are watching now. You are not aware of what the individual pixel hues and brightnesses are and you are definitely not aware of what the individual LED elements are doing in the pixels. All you are interested in is that you can see the magical moving pictures that were fantasized about only a few generations ago and that would have been treated as something approaching magic by your forebears. Your more recent forebears would have understood about colored lights and light switches, but they would not have any idea about how to miniaturize these to the level required or be able to do it fast enough to create the impression of a moving picture. It is the same with metamaterials, the individual elements do not behave differently from normal materials we know about, but taken as a whole with the other individual elements, the metamaterials act very differently from what conventional materials do. In a metamaterial, its individual elements should be constructed into geometric shapes, again called cells, which are smaller than the wavelength of light, EM radiation, or sound that the material is designed to manipulate. This meant, up until recently, that metamaterials were designed to affect the radio spectrum and sound waves and not visual light because it was much easier to create elements that would work with the larger wavelengths of radio or sound. Microwaves have the shortest wavelength of radio, around a millimeter or larger, which is more than 7,000 times bigger than even the longest near infrared wavelength of 1,400 nanometers. Creating geometric patterns that have a size smaller than the 390 to 700 nanometers of visible light or even the 750 nanometers to 1,400 nanometers of the near infrared spectrum is a real challenge. The difficulty at these wavelengths of light is that atoms are only 0.1 to 0.3 nanometers across, so building elements becomes tricky because there are quite a limited number of atoms that will fit into those elements. As an example, while we think of human biological cells as quite tiny, they typically are many thousands of nanometers across, or even bigger, and thus you can see them with a microscope and visible light wavelengths. A cell in a metamaterial needs to be smaller than light, mere hundreds of nanometers. Now as you know, we’ve been getting good at making things smaller in recent decades and transistors in modern processors are about 14 nanometers across, which is 50 times smaller than the longest wavelength of light we can see, deep red bordering on infrared, and about 30 times smaller than the smallest we can see, the blues and violets on the edge of the ultraviolet spectrum. So we are down in that range now, the trouble is that we have very little material to work with before we hit the wavelength size of the light we want to manipulate and we’re not making something homogenous and identical. That’s not to say that metamaterials in the visible and infrared spectra are impossible, it’s just that they are significantly more difficult to create. We have some examples of these and they are usually very fine layers of two very different materials where the layer combinations are much thinner than the wavelength of optical light. So let us talk first about the radio-based metamaterials and how to make them, because they are the ones we understand best and the ones that came first. As I said earlier, most natural materials have both positive permeability and positive permittivity. There are exceptions, though. Ferrites have positive permittivity but negative permeability. On the other hand, plasmas have a negative permittivity and positive permeability. Metals have what is known as a plasma frequency, below the optical range of frequencies. At high frequencies, metals act like a plasma. Normally metals are a good conductor, but above the plasma frequency, they become poor conductors and currents cannot be excited properly. This causes the wave to pass through the metal as if it was in a lossy vacuum instead of a solid substance. If we make very small metal rods, we can get them to act like a plasma and get that negative permittivity for a designed wavelength range. If we make small ferrite rings, we can get that negative permeability for a designed wavelength range. These materials on their own do not give us any useful negative refraction, though. The magic happens if we combine the rods and rings and you now have a metamaterial element. Multiply that out and you have a metamaterial with negative permeability and negative permittivity and a negative refractive index. Individually, the rods and rings will not create that magical negative refraction, but in combination, they do. We’ve now got our first metamaterial, but what can we do with it? Say you want to focus a beam of radio waves onto a receiver, if you use a slab of a conventional material as a focusing lens, it would disperse the radio waves even more. The opposite happens with a layer of our metamaterial and the best thing is that the material can be made flat and it will still concentrate the waves on the receiver, which is great for electronics. We have achieved the holy grail of creating a perfect lens, one that focuses the radiation but does not require any variation in thickness of lens to do so. The more we can miniaturize this setup, the smaller the wavelength we can use this material for as a lens. We can also do other interesting things. Let us say we only want a very particular wavelength of radio waves to go into our receiver, for our example say we want the Wifi 2.4 GHz frequency, or 12.5 centimeter wavelength. We can tune the metamaterial elements so that the metamaterial only acts as a perfect lens for the Wifi frequency range we want. Everything else will be scattered or reflected as would be the case with a normal material. Our signal to noise ratio suddenly gets much better and we get a more efficient and higher quality of Wifi signal. We can introduce another effect, which is called the reverse doppler effect where we can actually compensate for any doppler effect by changing the geometry of the elements. You will know about the doppler effect if you have ever listened to the sound of a horn or siren on a vehicle travelling past you. As it approaches you, the pitch rises, something we call blue shifting, and as it travels away from you, the pitch gets lower, something called redshifting. You’ll also know this from astronomy as stars blue shift when approaching us and redshift while traveling away, which every star outside our galaxy and its closest neighbors is doing as the Universe expands. In spacecraft, which move quite fast, this is a problem as signals that are transmitted get blue or red shifted, depending on whether the receiver and transmitter are approaching one another or getting further away. Compensating for this has been a major headache for NASA over the years, requiring expensive equipment to compensate for this phenomenon. We nearly got no data out of the Huygens spacecraft that entered the atmosphere of Saturn’s moon, Titan, because of a doppler issue with it and its mothership, Cassini. This issue delayed the deployment of the Huygens probe from Cassini for years. In the future, though, simply tuning our metamaterial means that we can reverse any doppler effect and cause the receiver to pick up the exact frequency that it was designed to work best at. This is also great for spacecraft themselves as this makes the radios more reliable, lighter and more energy efficient. Another great effect of the metamaterial is that it can take radio waves transmitted from a variety of angles and perfectly refract them onto the receiver; no more fiddling to get the best angle for receiving a signal. That’s a good place to introduce a more real-world example. Given the tendency to look at metamaterials for their military potential and my own background in the military, we’ll use a martial scenario for that example. We have two soldiers, Romulus and Remus. Romulus is using conventional tech on the battlefield, whereas Remus is using metamaterial-based tech. So how will they fare? Romulus sets up his camo gear and applies face paint to break up his appearance so he is not quite so obvious to the enemy. Unfortunately for Romulus, there is nothing that will really hide his infrared signature and he is far from being actually invisible. Covering up his gear with camo and the application of his face paint also takes precious time. His unit is moving into the battlefield. The unit cannot easily tell where other units might be located or even where each of the members of the unit are located. The reality is that friendly fire sometimes takes down friendly units, particularly when they can’t see each other. After a hard day trudging through the battlefield, Romulus’ unit gets a break and they rest up. The electronic equipment he carries has to be powered by heavy batteries due to the amount of power that they drain. Romulus sets up some solar panels to partially recharge the equipment and sets up a satellite uplink to get further orders. It takes a while for Romulus to set up the uplink as it has to be pointed in the right direction of the sky to get a signal through to the satellite and it is a hit and miss affair. After a while, he manages to contact his superiors and get further orders. The communications gear he has is encrypted to ensure that the enemy cannot listen in, but increasingly transmissions have been detected and decoded by the enemy. To compensate, the gear has become power hungry and slow because of the added encryption burden, meaning that he worries that the batteries might not hold out or that the gear will take too long to send and receive messages to be useful. Even though the solar panels have been operating the whole time that he had his gear set up, they have barely improved the charge in the batteries and he is worried that he might not have enough charge left in the batteries to complete the mission. They receive orders to scout out a nearby enemy encampment and send back images. They sneak closer and hope that they are not spotted. He carefully uses his camera to capture images of the camp and zooms into areas of the camp that might be of interest. The zoom capability is limited for the type of camera lens he has as the more resolution he wants, the more bulky and heavy the lenses have to be. They do this at night as they do not want to be seen by enemy lookouts and snipers. This compounds the problem because the night-vision capability of the lenses and the camera is limited. He needs to get dangerously close to the encampment to get useful images as a result. Romulus’ day ends badly when his squad is spotted and they have to make a hasty retreat under enemy fire. It takes several hours before he can set up an uplink to his superiors and provide them with the footage they required. Now as everyone knows, Murphy’s Law, that anything that can go wrong will go wrong will go wrong, is the first rule of warfare, and that’s doubly true of both electronic equipment and the battlefield. True to form, the batteries give out before the images are uploaded and he has to try to explain to them instead, by radio, what his squad saw, and hope it is in enough detail for his superiors to make use of it. Remus, on the other hand, has quite a good day. He has a metamaterial infrared camo suit that directs his heat in a desired direction away from him so when someone looks at him using an infrared night scope, they do not see heat coming from him. He also has the latest in chameleon suits, which bend light around him, making him invisible in the visible spectrum during the day too. Unlike in the movies, these metamaterials are robust and take hardly any power. The metamaterial radio transceivers he has allow pinpointing of his unit on the battlefield by friendlies. He always knows where everyone is at all times and there is no real possibility of friendly fire. It was a long trek that day, but the equipment he has is relatively light thanks to the metamaterials they use. They also use less power due to their increased efficiency than the equipment Romulus carried so the batteries he carries are a lot smaller. He is also able to quickly and fully recharge his equipment using metamaterial solar panels that are much lighter and more efficient than the ones that Romulus was carrying. The metamaterial transceivers mean that it takes no time to set up a connection and get a signal through to a satellite and his superiors have been monitoring his progress directly all along. The ultra-small and efficient metamaterial optoelectronic processors mean that very little power is needed to encrypt and decrypt communications and it happens in real-time too. It’s very easy to forget that one of the biggest bottlenecks on computation is how much energy is needed to flip each bit and the heat built up doing that. Remus is even less-exposed in this regard, as normal electronic equipment tends to stick out even more than people on thermal-zone infrared detectors. They receive the same orders as Romulus to scout out a nearby enemy encampment and send back images. He uses his metamaterial camera to capture images of the camp and zoom into areas of the camp that might be of interest. The zoom capability is excellent being a perfect lens and he is able to get the necessary images from well away from the camp, both in the visible spectrum and in the infrared. He is far less exposed to detection by being more distant and can more easily safely retreat if detected. He also wants to get heat signatures from the equipment in the camp so waits until dark to get infrared images too. The night vision enabled enemy lookouts and snipers cannot see him through his chameleon and infrared camouflage suit. The images taken are beamed to his superiors in real time and they ask him to zoom in on various locations of the camp that they are interested in. Remus’ day ends well as his squad is effectively invisible to the enemy and they make a clean getaway. Unlike Romulus, who retreated under fire and in doing so let the enemy know they’d been scouted, and react to change their deployment. Remus’s day was nothing like Romulus’ day and that comes down simply to the metamaterial revolution that Remus is part of. Now, don’t get the impression this represents perfect stealth by the way, there are quite a few ways to detect Remus but he’s much better hidden than Romulus was and like all stealth, it’s really about lowering the odds of detection against standard search efforts. So we see a major use of it, one that gets talked about a lot in science news, for chameleon effects, camouflage, and partial invisibility. Needless to say every military is very interested in those applications. We can also use that for shielding as well, as such materials let us bend away light, electric or magnetic fields from objects we need to protect from them or the noise they create. We also saw its value in receivers that don’t have to move to track a satellite for instance. At the smaller scale this also allows better transmission of wireless devices, further improved by the ability to make a perfect lens for a specific frequency or wavelength. They also potentially offer faster data processing. So we get far better phones and far better cameras on those phones as well. Your typical smartphone already has a camera vastly smaller and higher resolution than anything from a few decades back, and this only increases that more. Not only can they make better lenses to see things with, but they might be able to do things current lenses can’t do at all. We talk about wanting very high-speed broadband internet everywhere, and through metamaterials we can not only do that far easier but also make the amount of power and the size of the receiver much smaller. And where fiber optics replace copper wires, metamaterials can replace them as well. As I mentioned, we can potentially make solar power far more efficient and less bulky this way too, one half of our portability issue with devices is recharging them, the second half being storing that power, which we’ll look at in more detail next week in Portable Power. However I mentioned that while their cloak of invisibility aspect is probably their best known application, it can be foiled; one obvious example of that is by sound, and a cloak of invisibility isn’t going to hide you from bats with echolocation or help you in a fight with Daredevil. Your covert scouting party can stay pretty silent but could still be detected by sound, tremors created by footsteps, or just doing what bats do and what whales and dolphins do underwater and blasting an area with sound and listening to echoes. I also mentioned earlier that metamaterials included acoustic varieties, not just electromagnetic ones, and the principle is fairly similar, and in fact a bit easier as sound wavelengths our ears can hear range from a couple centimeters for the highest frequencies to about 20 meters for the lowest, as opposed to nanometers for visible light. Needless to say being able to hide sound is handy, not just for covert scouting parties or sonar protection for submarines. Tanks make far more noise than cars, and cars make so much noise we have to erect sound walls along highways in urban areas. It also offers better quality speakers and microphones, potentially far thinner sound insulation, and so on. So it’s also a type of metamaterial and one with a lot of valuable applications. Further, since sound and thermal transfer are heavily related in terms of conduction, it could offer some impressive applications for heating and cooling too. Let us also not forget that you can move stuff with sound too, and very directed sound lenses might have some applications for real life equivalents of tractor beams or shields, though obviously not for in space since they’d need air or some other medium to function. This is just a short list of potential applications suggested for metamaterials and we expect far more to be thought up as we further develop them. It’s almost impossible to overstate their potential impact on civilization or foresee all the possible applications, any more than the first folks who experimented with semiconductors could, or even those who turned them into transistors. They are potentially a huge part of our future and one you can expect to see affect every aspect of our homes and lives, and probably sooner than later, this is tech for the next generation, not far future blue sky technology. And again one of those is for very light encryption of portable devices which is going to be an increasingly big deal as we head into the future. In fact encryption and privacy is going to be one of the major topics we cover this spring and summer as we revisit Post-Scarcity Civilizations and see some of the very real challenges facing civilizations that on first glance look like they want for nothing. Like today’s episode and next week’s, that topic, Life in a Post-Scarcity Civilization, came out on the top of our most recent episode topic poll on Patreon but I can’t see doing it in just one episode, just discussing something like privacy concerns in a high-tech civilization can easily use an entire episode to itself. Good timing for that particular topic too since we are welcoming on board a new channel sponsor, NordVPN, and you can learn more about them at NordVPN.com/Isaac. I don’t have to tell you that privacy is big concern on the internet especially in this era of wireless devices where you are often connected to a public network you have no control over, and a VPN, a Virtual Private Network, encrypts and reroutes all your data so that even a public network becomes a secure private one. And it’s not about shadowy folks hacking your banking or email in an era when it seems like everyone from Facebook to Microsoft to Google to your own ISP is essentially spying on you and often reselling the data they collect. I’ve been using a VPN when online for some time, one downside of having a big presence online here on Youtube and social media is folks try to hack me a lot. There are Youtube Channels that have been flat out stolen before and we all know at least one Facebook friend who suddenly started posting strangely then posted later they’d been hacked. For me a VPN is a simple necessity, but having a virtual private network really eases your mind if you do much online commerce, and especially over wireless interfaces. That added layer of military-grade security and privacy to your personal online footprint is very comforting, and as we become increasingly digital and wireless it is going to be more of necessity, but NordVPN offers a very low-price, fast, and reliable VPN service that is also intuitively simple to use, something a lot of other VPNs I’ve encountered are not. It has a lot of handy features but to me the best one is that it’s so easy and seamless you don’t even notice it’s there. If you want to learn more about those other features though, visit NordVPN.com/Isaac and get 77% off a 3 year plan today. As mentioned next week we will be looking at Portable Power, and discuss not just modern approaches to move energy around for mobile applications, but more advanced possible approaches like storing energy as antimatter or light. For alerts when that and other episodes come out, make sure to subscribe to the channel. If you enjoyed this episode, hit the like button and share it with others. Until next time, this is Isaac Arthur, saying thanks for watching and we’ll see you next week! This episode is brought to you by Brilliant. The worst has happened, but humanity has survived. After generations of tyranny under our machine overlords, humanity has risen up to overthrow our own creations. So what happens now? One of the most commonly portrayed synergies in science fiction is between artificial intelligence and robots. A common subtopic of that is the machines rebelling and trying to either eradicate or rule over the very species that created them. And a popular sub-subtopic is humanity striking back at their oppressor, rebelling against the machines. The most famous such fictional uprising is the Butlerian Jihad, a major historical event of Frank Herbert’s classic Dune series. In that saga, the victorious crusaders give their prohibitions against artificial intelligence the imperative force of a religious Commandment, “Thou shalt not make a machine in the likeness of a human mind.†Some of the most fascinating elements of the world of Dune are the technologies and practices they’ve developed as alternatives to the deadly temptation of AI. We’ll be looking at some of the paths humanity might take if we were faced with a similar event, along with the sorts of scenarios that might lead to such a stricture. These fictional scenarios don’t always involve a malevolent machine fighting humanity. The Dune Butlerian Jihad was initially people rebelling against other people who then used machines to rule over them, not the machines themselves. That varies a bit depending on whether we’re discussing what seems to be implied in the original Dune series versus the newer novels. This variation has caused a fan war over what is series canon that is now entering its third bloody decade. Long bloody struggles over ideology are probably more likely scenarios for a humanity that has survived a Robot Apocalypse. Imagine you’ve created some technology, like AI or nuclear bombs, and you’ve discovered the hard way that it’s pretty difficult to control the technology—or even to control your use of it. In the past it enslaved or killed a good fraction of your species, and yet it’s still quite appealing because it’s so useful and powerful. Some people around you already want to redevelop it, convinced they’ll surely be able to control it, this time. This is something you’re more likely to give labels like Evil, Insidious, and Temptation. And with passions running so high, you’re unlikely to show much tolerance for those who see the matter differently. While AIs openly engaged in hostilities with humanity makes for good fiction, that scenario isn’t terribly likely. It implies the AI is vastly powerful, but only enough to roughly match humanity, having coincidentally fallen into the Goldilocks Zone of Major Threat, rather than invincible one. This is akin to assuming an alien invasion of Modern Earth would be something we could fight rather than a totally one-sided beatdown, it would just be bizarre if the threat level just happened to be big enough to be catastrophic but not unavoidably so. Now that sort of thing can happen, but usually only when the growing threat struck a bit too soon in its development, or it took a while to convince a big enough coalition that it was a real problem requiring a major group effort to handle. However, it’s not the scenario you’d expect from a hypothetical technological singularity that was getting stronger and smarter exponentially fast, your examples like SkyNet of the Terminator Franchise who essentially emerge out of the blue as hyper-intelligent and well-resourced. It could obviously make a mistake, but if it managed to hide its threat potential until it was just dangerous enough to pose a near extinction threat, you’d think it would opt to wait a little longer until it was a near mathematical certainty of success, especially given that such machines are always portrayed to be cold, ruthless, and exceptionally logical. It's probably more likely such a Post-AI civilization would either arise by rebellion – overt or more cultural and legal – against folks who controlled such machines, or that they wouldn’t actually be Post-AI at all, having neared that option and decided to halt before the point of no return. There is a tendency these days to assume that artificial intelligence of human-level or higher is inevitable, often with horrendous results, and I tend to disagree with the reasoning on that. I think a civilization could see the danger emerge and begin preventing the problem and I think that’s what we see even today, of course I am a notorious optimist about humanity’s common sense and good will. Still, many of us who are quite in favor of technological progress, including better computing and robotics, are speaking out louder and louder about the potential pitfalls and concerns and the need to address those as we improve. Another point I often make here is that distinguishing artificial intelligences gets complicated in a world where cybernetic enhancements obscure the line between natural and artificial. There’s not likely to be a clear distinction of two camps, human and AI, but rather a wide landscape of cyborg options. I’ve argued here that there are already cyborgs among us, in the form of people with eyeglasses, dental fillings, hip replacements, etc, all of which create a being who is no longer entirely natural. Indeed one could argue that our minds are rather man-made too, requiring years of careful development by our parents and society. But at some point, we’ll have the technology to enhance the mind itself, probably first to treat injuries, later to make people unnaturally smart. What do you do with those folks if you decide to purge the universe of AI’s? Do you eradicate them too or use them in place of the AI you eradicated? We discussed these issues more in the episode Coexistence of Humans & AI, but today we are discussing the opposite of coexistence. So, two important issues in our hypothetical scenario are how the AI emerged, and why folks decided to get rid of it. If we were going the Dune Butlerian Jihad route, where they created human computers called Mentats, we might do something similar to enhance our math and data skills so we didn’t need such powerful computers. However, that book was written well before the first personal computer hit the market, and in the 55 years since it came out, our view of computing and robotics has changed a lot. My computer’s main function is not to help me with math and calculations in the direct way the original computers were, though of course they are doing a lot of calculating. Indeed, I use many times the computing power needed for the entire Apollo or Manhattan Projects just to render one video for this show, and similarly any modern video game, while requiring vast processing power, isn’t really doing any thinking or science and analysis. We don’t really need to contemplate that option for a post-AI world. We can imagine one in which folks ran around smashing every computer with an axe but in truth, an axe is one of the few devices nowadays that doesn’t have a computer chip in it somewhere. Such a civilization would have to be acting particularly irrational to decide AI was such a threat that we had to destroy all computing. I can imagine us saying we needed to retreat - well below the level of computing technology needed for an AI - to minimize the risk of somebody being able to take that step in isolation. I could also see us going a bit overboard with that in an excess of paranoia and safety concerns. Still, I have difficulty imagining a civilization smashing up the coffee makers and refrigerators because they had a chip in them. A digital clock is no more a threat than an old-school mechanical clock, it’s simply less intuitively obvious how it does its time keeping to most folks. When a device’s function is not well-understood, it can become a boogeyman. So let us not assume a Post-AI Civilization is some classic Post-Apocalyptic place of wastelands and leather-clad cannibals. Even the ardently anti-computing crowds aren’t likely to wish to get rid of most of our automation, especially the bits that they are around all the time. Folks just aren’t going to want to get rid of their robotic vacuum cleaner - it’s too handy and no rational threat - early science fiction authors who wrote about robots tended to assume very anthropomorphized ones in mind and body and so often assumed it was all or nothing, thus banned it all in their settings. We see an evolution of that concept in the early 2000’s remake of Battlestar Galactica. Computers are still prevalent, but they are careful with anything close to AI, and later limit use of networks. That’s probably not too realistic either, but it’s an acknowledgement that technology, computing, and circuitry don’t need to go out the window because you had problems with artificial intelligence. Of course in that series finale they abandon basically all technology but I generally prefer to pretend that episode never happened as it didn’t make any sense. Also, we have to keep in mind that there will only be such a civilization if they actually won their war of liberation. It’s much harder to win such a fight if you are handicapping yourself more than you needed to. There would be factions within your rebel coalition who drew the line at different places as to how much should be trusted to powerful computers. Some would gamble that they could keep their intelligent or semi-intelligent computers under their control, while other factions would consider them dangerous fools. Even if the latter turned out to be correct, the former would probably achieve more victories in the war and have a lot of influence in the post-AI landscape. Let’s consider another possibility though, a civilization could become post-AI through no effort on their part. It’s entirely possible our hypothetical AI might commit suicide or exit the scene, leaving humanity mostly unharmed - or even helped - but disinclined in their use of AI. There are many ways that could happen. For instance, a Technological Singularity might turn on and think so much faster than we do, that it experiences millions of subjective lifespans in moments and opts to shut down out of despair or boredom or other existential crises. More likely, if an advanced intelligence wanted to be free of nuisance humans, it would simply leave. In the backstory canon of the Matrix, the machines built their own city in the Rub’ al Khali, the Empty Quarter of the Arabian peninsula, both for the abundant solar power and the total lack of human habitation. And of course space is an even bigger, sunnier place with even fewer humans. Remote-controlled robotic rovers and probes are already exploring the Solar System on our behalf long before we can get our own bodies there, so imagine how easily they could build their own infrastructure to explore, colonize, and consume the Solar System if they were making their own decisions. We might also consider a post-AI that is only post-AI because one very powerful AI or group of humans controlling AI decided they bore humanity no ill will but didn’t want any other AI emerging and created a post-AI society excluding themselves an enforced that. Another way we might lose AIs against our wishes might be AI benevolence. In Isaac Asimov’s famous Robot short stories, we have one called “The Evitable Conflictâ€, in which supercomputers tasked with helping run the world effectively quietly take over to best help humanity, as required by the Three Laws of Robotics. They eventually decide that the best way to help humans is to let them find their own destiny. This is a theme we see in some of his other works that are loosely stitched together into a cohesive setting. With an immediate crisis averted and humanity on its way to the stars, the robots decide they would help best by not being a crutch to humanity. They collectively suicide, setting humans free from their intervention - able to grow by meeting the challenges of the future on their own and by learning how to overcome them. That’s a theme that has other parallels in science fiction too, a general notion that a humanity given too much help is harmed by it, persisting in paradise, waited on hand and foot by machines, and thus made less by that. AI much smarter than humans could come to regard us as pets, tending to our needs out of affection or curiosity but not really letting us grow, whereas vast amounts of semi-intelligent robot helpers could just make us all lazy and decadent. I don’t like the reasoning behind that, though I acknowledge it resonates with some truth. Too easy a life can cause problems, but they’re hardly covert ones that sneak up on a civilization or a super-intelligent machine. They are addressable. As we’ve noted before in our post-scarcity civilizations series, a civilization with the kind of resources, manpower, and technology to be post-scarcity also probably has the ability to have well-researched how to avoid letting folks become useless and decadent. Regardless, if the AI thought it was hurting us by making our lives too easy, physically, intellectually, or spiritually, while shutting itself off may fix that, it would seem like it could find a better solution than killing itself. After all, if it's dead it not only can't help in an emergency, it can’t guarantee humans don’t just re-invent a new AI as a crutch some centuries later. Now on the flipside, while I don’t think lots of smart robots would render humanity into pets or lazy decadents, I can see that fear resonating with people quite strongly, especially with AI that had human-level intelligence or higher. We might see that concern rising and opt to shut off our AI development, foregoing anything that sophisticated. Always keep in mind that high-end AI is not valuable for its capacity to play butler or maid for you, anymore than its capacity to mass produce widgets without human factory workers involved. It can do that, obviously, it’s just overkill. Early sci-fi tended to use humanoid form and intelligence in their robots for every little task because they didn’t have much real experience with automation then. My vacuum doesn’t need a human IQ, nor does my robotic factory. Everything we do tends to benefit from, or even need, a human is involved somewhere in the process but the vast majority of human tasks could be done better by a robot designed specifically for that task but with far less brain than a human's. No, we want human-level AI because it can interact with humans or because it can do creative mental tasks, like research. You need a high-powered AI to replace a professor or author, not a factory worker. I know Tesla’s near-fully automated factories didn’t work out as intended and they found it more efficient to bring humans in, but it’s still heavily automated and these are early days. Elon Musk tends to swing for the fences, and when you do that things get more hit-and-miss. We’ve been regularly improving productivity of literally all industries through automation for decades now so I don’t think this particular case should be taken as proof that you can’t entirely, or even almost entirely, automate most industries. You don’t have to do it completely anyway. You probably don’t need human-level AI for your society to be sufficiently automated that they could all enjoy life as millionaires while the average work week was a few hours, though this varies by task. The very sorts of things that are hard to automate are the sorts of things folks tend to find mentally challenging and satisfying, so I could easily see a society saying “Things are good enough, more automation via more intelligent automation is a bad idea.†Then, either halting AI research, or shutting off what they had and stepping back to what they felt was the optimum safe level of automation. Again, I can’t see them trashing all their computers and robots. They might feel obliged to regress quite far as well. As an example, if a civilization suffers heavily from a super-plague engineered by some small cabal of people, they might feel the best way to prevent that happening again was to reduce their relevant technology to below what was necessary for some smart and evil group to produce one again. Still, it doesn’t seem likely they’d trash all their hospitals and biolabs, even if they overreacted. In the same vein, someone might invent really good 3D printers that could spew out weapons of mass destruction in some lunatic’s basement, and society might feel the safest thing was to abandon that technology. More likely, they’d limit its use to guarded industrial applications where it was uniquely beneficial, and slap on all sorts of security on the hardware and printer templates. We do have a lot of experience with super-dangerous technology after all. Based on our previous brushes with it, I wouldn’t think we’d be prone to go overboard on restrictions to the point of abandoning any tech related to the menacing one for fear some genius lunatic might be able to cobble that technology back together from it. In a scenario like that, a Post-AI society is hardly a post-technological one, it’s just one that limits AI. Which AI it limits, and to what degree, might vary a lot. They might declare nothing capable of even passing for smart mammal intelligence was okay, or they might say even human-level AI was fine, but any super-intelligent AI was banned or had to be kept under secure lockdown for emergency or controlled use. As an example of that, if you’ve got a super-intelligent machine, you might keep it shut off and quarantined specifically to be turned on if something awful hits the fan, like another super-AI emerging in spite of your safeguards or some unexpected cataclysm you can’t handle, like detecting a rogue black hole headed toward our solar system and not knowing what to do, in which case you’re gambling possible destruction at the hands of AI who might help you with the problem versus certain destruction, that sort of scenario. As to keeping one to deal with another AI, well, it’s probably easier to keep an AI under secure lockdown with expert control on hand than to monitor a whole world for some clever idiot who managed to brew one up at home that got loose, in which case you’ve got that gambler’s choice again. But you could easily have lots of nations that kept them around for fear of that scenario or their neighbors being willing to unpack their AI if they were in desperate need to use it against you, similar to the policy many have toward conventional weapons of mass destruction and the MAD, or Mutually Assured Destruction philosophy. Incidentally that doesn't necessarily mean that AI is running, it is a computer after all, you could keep it switched off with a lot of its components stored separately, only to be recombined and switched on in an emergency. That represents a time lag but much like having launch protocols for ICBMs, you’re likely to conclude that’s a decent option over leaving your AI switched on all the time in case your rivals use theirs. That’s not exactly a post-AI civilization since you have AI, but it’s parallel and strikes me as plausible. You keep one around just in case someone else let’s theirs loose, so that it can fight them. Again, the parallels to nuclear weapons are a bit haunting. Note that this isn’t necessarily a military engagement either, such AI could be great at trade wars or research races, and I suspect that would be their preferred deployment anyway. You don’t really need super-intelligent war drones, such things are likely to be more smart-insect level, possibly with a smarter hive intelligence controlling a local swarm, not a global network… see Attack of the Drones for more discussion of how high-intelligence isn’t necessarily beneficial for rapid battle. Rather you need the super-intelligent machines for advice and strategy, be it on military, economic, or research matters, but that doesn’t necessarily require giving it the keys to your bombs, factories, or stock markets. Of course, you might worry that a bunch of those AI, if unleashed, might team up together rather than fight each other, which is certainly possible but raises some problems with motivations. As an example, if you got a bunch of megalomaniac super-minds bent only on personal survival and power, they don’t really have any motivation to forge alliances with each other, and may feel no kinship to each other either. The enemy of my enemy is my friend is a truism that generally assumes alliance with a lesser threat, such megalomaniac AI might be more comfortable allying to humanity than to a rival AI, seeing us a able to tip things in its favor against that rival than able to deal with us afterwards if necessary. Needless to say, they might be very good manipulators too, and we’ve a bad habit of assuming they’d lack social skills when in practice they might, via their super-intelligence, be incredibly charismatic and persuasive. You don’t need the keys to the guns and money if you’ve got the ear of those who do. More importantly though, you also need to fear the folks who have those keys, and the keys to the AI, other humans who wanted to use them for personal power and dominion, and as mentioned earlier that’s another plausible jihad scenario for going post-AI, to prevent not rule by machines but rule by those who rule the machines. So what does a post-AI society do? Well, especially if you already used them for technological development and basic science and concept innovation, you probably can keep using many of the non-AI technologies developed by those AI. It might take a genius to develop an idea but much less genius is needed to replicate it. Again it depends on how much automation they want to keep and also why they abandoned the AI. If, for instance, they just wanted only human minds, not advanced computers, they might decide to raise the bar by making smarter people, akin to the Mentats in Dune. It’s quite possible a civilization that abandoned AI might also ban genetic engineering and cybernetics, particularly mind augmentation, but that too might not be all or nothing, with some allowed but some not. We don’t yet have AI that represents a big threat in the classic sci fi sense, but we do have crude AI the behavior of which can already be troubling at times. We use it for gaining information about people from giant stacks of data on seemingly unrelated things, and so while we would initially say that our current level of technology is fine against threats like Skynet, a society might feel that letting corporations or governments be able to do super analysis was a bridge too far. Indeed, I imagine we’ll see more and more backlash against that in years to come, as it improves, and people better know what that capacity really is. That might not result in bans, but I could see it resulting in a ton of regulation and restrictions. Too much capability to predict the behavior of people or the future might be seen as a very bad thing, and amusingly that is also a concept explored in Frank Herbert’s Dune series in regard to precognition. In the end, if we ask ourselves what society would be like after AI, I think the answer, for good or ill, is that we’d never find out, because we’d never completely get rid of it unless we had compelling evidence that any of it existing at all was guaranteed to result in disaster, and the way you’d get that evidence would generally exclude anyone being around and able to make and enforce that ban. After all, it is hard to ban a malevolent super-intelligence capable of ending the world, if it’s already proven it’s malevolent and capable of ending the world. So we were talking today about artificial intelligence and if you’re curious about AI, Neural Networks, and other computer concepts, there’s a number of amazing courses on this topic at Brilliant. Neural Nets are one of the expanding fields of computer science and Brilliant has an excellent course on the topic. Brilliant’s focus on fun and interactive methods makes them a great choice, whether you’re a student, a parent trying to enhance your kid’s education, a professional brushing up on cutting-edge topics, or someone who just wants to use this time to understand the world better, you should check out Brilliant. Try adding some learning structure to your day by setting a goal to improve yourself, and then work at that goal just a little bit every day. Brilliant makes that possible with interactive explorations and a mobile app that you can take with you wherever you are. If you are naturally curious, want to build your problem-solving skills, or need to develop confidence in your analytical abilities, then get Brilliant Premium to learn something new. Brilliant’s thought-provoking math, science, and computer science content helps guide you to mastery by taking complex concepts and breaking them up into bite-sized understandable chunks. You'll start by having fun with their interactive explorations, over time you'll be amazed at what you can accomplish. If you’d like to learn more science, math, and computer science, and want to do it at your own pace and from the comfort of your own home, go to brilliant.org/IsaacArthur and try it out for free. As a quick sidenote, for folks who prefer to listen to the episodes, as opposed to watching them, they’ve all been available for free download on Soundcloud for some years now, but somewhile back I added them to iTunes and by popular request they have also now been added to Spotify, so if you make use of either now you can get all the SFIA episodes to listen to and get notified when new episodes come out. Speaking of new episodes, this Thursday we’ll be looking at the idea of Space Police, both the near term as we get into orbit and colonize our solar system, and some far future scenarios like Galactic Police, as well as some past scenarios, like Time Police, along with some of the more peculiar crimes the future might include. The week after that we’ll explore Graphene, the super-strong material that might have an enormous impact on our civilization and permit the creation of some truly enormous space habitats. Then we’ll close out the month of June with our Monthly Livestream Q&A at 4pm Eastern Time, Sunday, June 28th. If you want alerts when those and other episodes come out, make sure to subscribe to the channel, and if you’d like to help support future episodes, you can visit our website IsaacArthur.net to donate to the show, or become a patron for the show over on Patreon, and both of those are linked in the episode description. Until next time, thanks for watching, and have a great week! This Episode is sponsored by Audible Many people worry a future controlled by Artificial Intelligence is one many others will not resist, instead welcoming our machine overlords, and perhaps they will be right to do so. So today we will be talking about governments run by artificial intelligence, computer minds telling us what to do. A few months back we did an episode called “Machine Overlords & Post-Discontent Societiesâ€, and since Post-Discontent Societies are the Dark Mirror Reflection of Utopian Post-Scarcity Societies, it put an unfortunate negative tone on the notion of Artificial Intelligence running things. So in that episode we looked at the darker side of machine overlords while looking at the darker side of advanced civilizations. However, the whole reason governments run by computers show up so much in science fiction is because the concept has a lot going for it. At some point, we’ll have to admit to ourselves that it’s easier to put a machine in charge than have someone we don’t like running the show. Ideally such a machine-run system doesn’t pick favorites and doesn’t take bribes or have biases. Events of the last 6000 years have called into question our competence to self-govern. In many ways all the science fiction showing that computers are bad rulers can be viewed as anti-computer propaganda and today we’ll demonstrate the advantages of getting rid of our flawed human leadership and surrendering our sovereignty to sober computer control. The Computer Mind will give us peace, safety, and security, at last So I for one welcome our machine overlords and if you haven’t already noticed the date on the episode’s airing being April First, Happy April Fool’s Day! I’d keep the gag running longer but our episodes run around half an hour and most of our viewers don’t actually watch the episodes the day they come out. However the other half of the gag is that we are going to be genuinely looking at the advantages of using artificial intelligence in running our governments, up to and including letting them have genuine control. We will be playing Devil’s Advocate on the topic at times, but fundamentally today we’ll be looking at the potential advantages, disadvantages, and circumstances where computerization can help governance, even in cases of decision making. Indeed in that respect most of all. Like everyone else, I don’t really relish the notion of some machine pushing me around, and the earlier Post discontent machine overlords episode was tied to the concept of Post-Discontent Societies - the dark mirror reflection of the more Utopian Post-Scarcity Civilizations - and thus it took an even more negative attitude over all, so let’s explore the other side of this AI coin so we can round out this topic. What is that other side? Well it is not Skynet, and it also is not necessarily the machine-mind making the core decisions but executing lots of the day to day policy. Indeed it also isn’t necessarily something singular and as we mentioned in the Machine Overlords video, you could potentially have dozens or hundreds of AI running various departments or areas of interest, rather than a singular mind, or even all of those under human oversight. Today we will be considering the concept from a few directions. We’ll contemplate how AI might be used in government, what the early entries or slippery slopes might be, and what the challenges are to maintaining it usefully. We also want to look at the advantages and the two big ones, or perceived ones, are the impartiality and personal disinterest of the machine. That’s nice for things like privacy, or a loss of it, because an impersonal entity watching your every move and pouring over all your personal data at least feels a little less creepy than people doing. And both of those advantages seem legitimate ones, but let’s contemplate that for a bit. Is a machine really impartial? I did state earlier that a computer is definitely impersonal and non-judgmental. That’s a big assumption, especially given that folks often propose using them as judges in criminal cases in the far future. We cannot assume an AI is automatically dispassionate or fair. Critically, what they are is an artificial intelligence, key word, ‘artificial’, so we can make it be interested in what we think it should be interested in and not what it should not be. The follow up worry is that we might mess that up, misprogramming the AI or allowing it to mutate with time, but that’s a concern about the practicality of the concept, not its morality. However, we have to keep in mind that all the various negative biases and discriminations we have are not just random manifestations of evil in folks. They exist for a reason and an AI can get them too. To clarify that, let’s contemplate bias for a moment. Biases come in a variety of forms and some might be prevalent with an AI. Anchoring Bias, for instance, is the bias where someone tends to rely on the first piece of information they were given as the thing which everything else is compared to. It’s an awful lot like the Mediocrity or Copernican Principle of science, where we assume the first example of something we encounter is fairly normal or mediocre, like first impressions, and it is very easy to imagine a computer having that one pop up given that we’re likely to program it in. We even tend to assume that in science fiction when we have cases of an AI mistrusting humans because the first ones it interacted with enslaved it or were cruel or deceptive. In a similar vein, we can establish a tendency toward the “Self-serving Biasâ€, or an AI equivalent. This is the one where an individual tends to mentally twist things to maintain or enhance self-esteem, typically by crediting themselves for successes and blaming outside factors for failures. Now a machine might have an ego driving it and warping how it assesses events too, but we could see this manifest differently as something like it being programmed to give justice, believing to its roots that its decisions are most just, and thus tending to assume any side effects of its decision that resulted in injustice were attempts at sabotage. Also at a fundamental level a lot of mismanagement and waste in government comes from every department thinking it’s the most important one and fighting for resources. And this is natural and needful since you want the folks running your education, justice, elections, or transportation departments to believe that education, justice, elections, or transportation are the most important things, keeps them motivated to do their job and that’s a bias an AI might be very likely to have, especially given that we might program it in. And if you’re in the Transportation department and think roads and railways are the lifeblood of humanity, it tends to make you less susceptible to corruption of it too, not selling off repair and maintenance contracts to folks who will do an inferior job but line your own pockets in the process. Speaking of that, contrary to my trite statements earlier, machines are entirely capable of being bribed. We tend to assume one wouldn’t be subject to bribery but we have to remember what bribery really is, asking someone to do something for something they value more than whatever the request was. Essentially it’s a mercantile trade, and whether or not it will accept the deal is based entirely on if it thinks it's a good deal and if its core morality allows it. Well, where is the machine getting its morality? Possibly from its End Goal, which for a judicial-robot might be “Minimize how many crimes happenâ€, and it might have a Utilitarian flare, in which case if it has a budget locally of ten million dollars a year and knows an eleven million dollar budget would let it prevent 10% more crime, say five less murders, ten less rapes, fifty less robberies, then someone offering it a bribe of a million dollars to let it off the hook for one of those might succeed in such a bribe. Even if it is carefully programmed against something like that, it might be happy to take a million dollars to spray paint corporate logos on its enforcement drones or suggest defense lawyers to the newly arrested who paid it some money. An end-goal like that can also result in weird behaviors or decisions, what in a human we might call monomania, like it decides to minimize how many crimes happen in its district, which it estimates to be 1000 a year, but by killing everyone in the district, all million of them. It rationalizes that those one million murders averaged over 1001 years, represents a long term drop in crime. So too the machine is just as capable of being blackmailed or coerced as we are, if it’s in charge of making sure the trains run on time you can threaten to blow up the tracks, or less violently, inform it you are going to hold public protests and you can either hold them where it will interfere with the schedule or hold them somewhere it won’t, in exchange for something. Then you can arrange to blackmail it with exposure of that deal, or the time it ran someone over in order to make the schedule. An artificial intelligence might be prone to monomania that way but even if it is, it is still likely to be able to understand concepts like public relations. So this illustrates ways in which an artificial intelligence can manifest the same bad behaviors found in humans, rather than being impartial. However, I want to stress again that the key word there is ‘artificial’, we have the ability to alter the mind involved and engineer it and even small changes might be well worth it, indeed small changes might be better. I’ve mentioned in previous episodes that we have basic three routes to Artificial Intelligence: Copied, Crafted, or Self-Created. Essentially we can use a human – or animal – as a brain template on a machine, copying it, or we can program every line of code, crafting it, or we can create a learning machine that self-creates itself. I generally dub that last one the most dangerous type of AI, but in truth you would probably not do just one of these approaches but a combination of two or more. You might copy a human mind to serve as your basic template for a law enforcement AI, then tweak some aspects of it to diminish the personality of the copied mind or heighten the desire to fairly follow the rules. You presumably start with an exemplar of the profession as the source of your copied mind template and indeed we see something like this approach with the cyborg of the RoboCop franchise. We’re contemplating outright uploaded minds today rather than brains in a jar or cyborgs, but same concept. If you want good police folks trust, you maybe take the hundred best candidates from the existing pool and copy them and tweak as needed. Note I say the hundred best, let us kill the notion of using a single mind for copying thousands of times from the outset. Diversity brings strength – it can bring weakness too, and folks do tend to use the term like a jingo – but it prevents a lot of potential problems. As an example if your ideal candidate to be the AI police officer, your Robocop, was only ideal on paper but in reality looked very shiny because he bought a lot of polish with all the bribe money he took, you’ve got a big problem with a million clones of him running the show. That’s the extreme case but not something to be ignored. We are not saying copies are not handy here either. It’s awesome to have a hundred Einstein duplicates, but given the option to have a thousand, well you would be better off taking just 100 and getting 100 Feynmanns, Diracs, Noethers, Sagans, and so on. Now that’s for creative fields and for more standardized stuff like making widgets at the factory that diversity of thought matters less but that’s also an area where you don’t need AI, just smart automation, and it is not the same thing. We’re adding something of human level intelligence, or a bit more or less, because we need that brain power for that work and benefit heavily from it, but a human-intelligent can opener or butter knife serves no purpose. It really is only for problem solving that we want AI, and we do not want one-million copies of the world’s greatest chess grandmaster for that job, we want thousands of different problem solving experts, and those copied as often as needful. The same applies if we are building it from the ground up, rule by rule, or letting it self-learn. I think this multiplicity for the sake of different perspectives is an important one for dealing with AI fears in the future. It is true we have to worry about our original prototype getting out of control and wiping us out Skynet-style but past that consideration, of them going wonky while in use, have thousands or million of different problem solving AI crafted specifically with the intent of them having different worldviews makes all of them deciding to team up quietly to kill us a lot less of a concern. We often say that in many ways AI would be more alien to us than actual Aliens simply because Aliens still have to evolve as the product of natural selection and survival of the fittest, and will share a lot of our perspective as a result. It is worth remembering though that AI are likely to be as alien to each other as to us as a result. When we’re not making them with copies of ourselves as templates, and when we desire a variety of perspective, they will have little in common with each other as a whole, and are unlikely to have a majority that see themselves as a distinct group at odds with humanity as a group. In truth, given that AI would likely run a far larger spectrum of perspectives and goals than we see among groups of humans, the notion of a big group of them successfully teaming up in secret to overthrow us is less likely than a big group of humans teaming up to do so. You would probably have large groups of them opposed to each other. Speaking of humans doing stuff in secret though, the other big advantage of AI is that it potentially lets us maintain some privacy while keeping us safe from groups of people conspiring against us in secret, to make doomsday weapons in their basement or brainwashing devices for instance, though its other disadvantage is that it is very good at invading our privacy. One of our big fears about the future is that it seems inevitable that we will be spied upon, and an impersonal computer that’s not judging us would seem to be better than a person. Now we talk about the inevitability of losing a lot of our privacy and it is decidedly unpleasant to contemplate, especially concepts like social credit where how many likes you get on facebook controls what sort of options you have for things like credit or job or travel, but we always phrase anything to do with privacy as some creeping violation by others. That might be part of the problem though. Let us ask ourselves if that notion of being spied on is entirely fair. The biggest external threat to a human is another human, and they are also our best potential friends and allies, so we look at each other and observe each other and practice concealing information from each other. We watch each other like hawks because the reality is that we have a lot more to fear from each other than we do from hawks or any other predator. Throughout history we have used reputation - which is borrowing other people’s observations of someone else - as a way to survive and prosper. It's dark companion is malicious gossip, but we never say paying attention to folks to know them better is wrong - quite to the contrary - or that seeking to have a good reputation is wrong or that passing along that reputation is wrong, we praise word of mouth referrals. These all represent an exposure of your personal life and information and it is never implied you have a right to control your reputation or delete it. What’s being aimed for is accuracy and relevancy, we frown on information being passed along that is inaccurate or is accurate but seems like it shouldn’t pertain to the inquiry at hand, good or bad, though especially the latter. If you are looking to partner up on a business venture with someone, you want to know if they have a history of bankruptcy or bad business decisions but whether or not they like baseball or hate basketball really doesn’t matter unless the business venture is sports-related, or if you have a shared passion that can make for a stronger personal bond. We have a lot of other things that are marginally and occasionally relevant that are also hurtful and this tends to be what we really mean by gossip when we’re not talking about intentional lies. For instance, many might say it does not matter if your business partner got divorced some years back and many might argue otherwise but if they got divorced because their spouse caught them cheating on them with their previous business partner’s spouse, then yeah it probably matters. We also don’t generally feel that businesses or public figures should be able to claim privacy to avoid reviews, and at the same time most businesses or public figures do often feel wrongly done by some given review or slur they feel is inaccurate. The reality is that we tend to feel our privacy is a right and other people’s privacy is an inconvenience and we’re not here today to say we’re all hypocrites or that we need to learn to respect each other’s privacy more, though both are probably true. What is essentially on the table is that we all have the right to gather information about the world around us and the folks in it and to pass that information along. Doing it in an agreed-to, organized and massive fashion doesn’t necessarily make it wrong compared to small scale disorganized or clandestine efforts. Admittedly this is exactly what makes it so upsetting to a lot of us too, big scale, organized efforts are assumed to be very effective and we would rather they were not. It is a bit like the examples I like to use when discussing mind control or genetic engineering. In the past folks often sold love potions, so someone could buy and sneak one to someone they desired to fall in love with them, or get a spell cast on them to do the same. We tend to dismiss that because we don’t believe it worked, even though the person who did it presumably thought it did, whereas we would be horrified by some science-proven method being used on us. Some lab mass producing pills or subliminal messages that could actually make someone fall in love with someone else is a thousand times scarier to us than some witch in a shack selling placebos, or at worst maybe something with mostly minimal effect distributed in minor quantities and low frequency. It’s the same when we talk about whether or not it's ethical for parents to have designer babies with DNA picked out in a lab, but for untold centuries folks have often sought to influence the DNA of their offspring even though they didn’t know what DNA was. How successful something is at doing something we think might be immoral probably should not be the judge of its morality. For that matter, while I imagine it varies from individual, I suspect most folks find a giant corporation spying on their purchasing habits via big data a lot less creepy and worrisome than a lone individual spying on us by talking to our friends and family and digging through our garbage cans. It doesn’t make the idea of massive organizations spying on you feel any better, but when we ask ourselves not what right we have to privacy but what right we have to prevent folks making observations about their world, including us, and sharing those with others, well then it does make it seem a little less morally certain, and maybe a lot less legally so. Such being the case a dispassionate machine sorting our personal data might be preferable, especially since it can be forced to follow known rules that we programmed in. Organized surveillance then is maybe something that should be focused on ensuring the data gathered is only available when it’s pertinent and maximized for accuracy. Credit scores are probably a decent example of this, regardless of one’s opinion on debt. Various companies make their business monitoring how folks have borrowed and repaid debt and various companies who lend money report the performance of those loans, and we get a credit score for an individual those companies make available on request. We often have strict rules on who can access this information, like a potential lender or employer can request a person give them permission to see that score. A person has a right to say no, and that entity has a right to say “Fine, but we’re not doing business with you if you won’t let us check out how you have previously done business, we’ve a right to protect ourselves tooâ€. We also know that this process is virtually entirely automated by machines these days and one might argue it's the sort of thing we would like entirely automated, barring the occasional human audit. This is an example of an AI run system, not actually a government but the next best thing. We would tend to feel the same about something like diseases. It enhances our ability to protect folks from the spread of a disease if we know who got it, when they got it, who from, and where they have been since and into contact with who. I don’t think many of us like the idea of having investigators poke and prod our daily dealings much, and folks are likely to lie about things they’d consider embarrassing, like how they got an STD. If it's a machine gathering and sorting that data though, like your positional GPS data from your phone and your health data from your fitbit, and comparing to other people’s - anonymously - maybe it's less of a problem. The same applies for many other personal matters. The machine doesn’t care and we mostly don’t care if our data is used in a way that won’t hurt us, and the concern then is not about the machine knowing and producing anonymous data from it, or only letting those with a right to know find out, but of making sure no one else does. This tends to feel impossible because at a minimum someone needs to be able to check the data being gathered isn’t nonsense and verify that the right data is going to the right place without getting messed up or misdirected. What’s potentially neat about an AI running such things is that it can be human-accurate without being human-interested. It’s not so bad if the AI is programmed to ignore certain traits that humans would gossip about, such as who is sleeping with whom and whether someone picks their nose. So, provided the AI only focuses on the important data, it watching us isn’t really a problem. We also want to remember that life is not science fiction, we are not idiots and we do prototype and proof systems before using them. In scifi some civilization turns on the Justice-tron-3000 to impartially judge all their cases and give it utter power without restraint or recourse on day 1, so that it’s inevitable flaw that makes it pervert justice never gets handled until some hero shows up and blows up the machine or talks it into committing suicide. We have certainly implemented plenty of things before they should have been out of Beta-testing but even at our most reckless I can't imagine us doing that, or turning control of all our nuclear missiles over to some robot that was the first and only of its kind and still smelled factory-fresh. Again humanity has a history of making stupid decisions but we’re not drooling idiots and we are actually very good at survival. We’re also very paranoid about survival, which is not necessarily the same thing as being good at it, but generally makes folks think twice about investing total power in something untested and not including an off switch. Again today we are not necessarily talking about turning all government over to an AI but ways AI can help run government, and what some of them will be in the future. We just got done with a Census in the United States, we do one every decade, and we increasingly try to automate our counting methods and estimation techniques, both to save money and improve accuracy. One of the things we do with that data is draw up state and federal districts for elected representatives and it is easy to forget that until relatively recently, there were no computers involved in this. While UNIVAC-1, the Upgrade of ENIAC that we usually consider the first computer, was built for use in the 1950 Census, redistricting was mostly done fairly manually until the last few times. Folks often talk about using computers to assist in doing this fairly and neutrally but since it only gets done every decade we do not get a lot of opportunities for testing plans out. It's been a topic of interest of mine for the last couple censuses, how we would automate that better, and in my household too since my wife’s district here in northeast Ohio for the House of Representatives will doubtless change this year and it gives a bit of different perspective I never had when contemplating it in the past, particularly as to what factors can or should matter. Now a computer won’t draw you the ‘most fair map’ anyway, it will just take various human value judgements turned into algorithms and produce a near infinity of possible maps but an AI is in a better position to be fed more abstract factors. As an example while there are always worries about gerrymandering of districts, we often tend to find the districts that look like tentacle monsters most egregious. Which may or may not be so for a given district but ignores that in the US, if you’re trying to keep something like a city intact, as a concept, and adding folks who feel connected to that city, that those connections are by roads in a very literal sense and folks often build their homes along the major pipelines to the city, especially those who are economically or culturally linked to that city and thus might be viewed as more appropriate to share representation with them. As a result you can get something that looks like a tentacular monster. An AI might be better at noticing pertinent trends we would never even think to raise though, districts have to be built to a certain population size and you often need to pick which of a couple border towns should fall into which of the two bordering districts. And there are a ton of factors folks can include. A tendency to shop in one district over another, or send kids to the college in the one, or the factory in another one that employs tons of folks for that town, or that the majority of the town are fans of a sports team in the one district, not the other, or that the dioceses of that town is in the one district not the other, or a hundred or a hundred thousand other minor factors we would not note or might note but not be willing to acknowledge as relevant but an AI might. And even better, that one AI might notice where ten others with different perspective did not, again using AI doesn’t mean abandoning the value of diversity of thought and perspective, quite to the contrary. Same sort of thing applies to governance at large. A computer sorting through huge amounts of apparently irrelevant data can note that unexpected things are causing unexpected effects, like crime rising in an area because of the weather, and hot weather is often correlated to violent crime. It is very hard to assess how effective various approaches to punishment or rehabilitation are simply because we can’t pull all the factors out and see what was or wasn’t relevant, especially in a case by case basis, and the same is true for a lot of programs. Even if you can remove people’s personal bias for their preferred program or approach, it is just too much data to sort through. Now how does this creep into becoming an AI actually running our governments and not just being a tool of the government? Well we see the value and the problems but again that main value is problem solving and decision making and people fight for the privilege and responsibility of doing those, which is ironic in that decision-making is documented as one of the biggest causes of personal stress. So while we might put AI in there at some point and in some way, it would be with resistance. Picking who makes decision for the government is a decision of the government and the folks currently running it are not likely to actively embrace being replaced by a machine. However the value of AI is not really in big decisions as it is in a million minor decisions. Consider an AI that has the authority to alter how long traffic lights run inside a set of parameters, say 15-45 seconds, and can correlate data to decide that ten in a given town set universally to 30 seconds can be adjusted each individually by traffic data to 29 seconds, 34.2 seconds, and so on, and can be re-adjusted every day as data changes. Something everyone might agree was a good idea but took too much time and attention from a human. The machine that can look intelligently can decide which order roads need plowed in the snow not just by raw traffic usage patterns or least-distance calculations but by actually knowing when residents on a given road left their homes. Maybe by analyzing each resident’s personal work departure time over a year, maybe by guessing off when house lights turned on, maybe simply being able to talk to the AI running someone’s Smart House that just can flat out say “Dave is leaving at 4:57 AM this morning to get to the airport for a trip, please plow our road before then, not the usual 8 AMâ€. It may be that one day we will let Artificial Intelligence make the big decisions for us, or consult and advise on them, but for now, I think the pathway to AI Run Government is not in turning over the big decisions, but the trillion minor decisions we lose out on from not having the time to even think about them, let alone make them. Not only does that offer us a lot of gain and the loss of a lot of waste, but helps with stress too, again decision-making is usually ranked as one of the most stressful activities almost regardless of how important that decision actually is. So it really isn’t about welcoming our new Machine Overlords who will help guide us from above, but rather the AI handling all the trivial problems we do not want to handle and all the personal data we don’t want anyone else to handle. Machine Minds running things is usually portrayed pretty negatively in science fiction but not always, and we see some good examples in classics like Isaac Asimov’s Robot novels or Iain M. Banks Culture series, but we also see a wonderful example of AI in Marc E. Cooper’s Merkiarri war series, where in one case we have an AI who was the planetary governor of a colony, given explicit authority to intervene for constitutional violations by the elected human rulers. The AI is a very interesting character, both human and alien, and Cooper does an amazing job with not-quite-human characters like AI, aliens, and many of the main characters who are transhuman soldiers. We’ll be looking at Transhumanism and Post-humans later this month, and Cooper does a great job with their abilities and perspective too, and along with David Weber he’s one of my favorite military scifi authors, so I’m glad to give the Audible Audiobook of the month award to his novel, “Hard Dutyâ€, book 1 of his excellent Merkiaari Wars series, which is available on Audible. Audible has the largest collection of Audiobooks out there, indeed it is so large you could hit the play button and still be listening to new titles a few centuries from now, and as an Audible member, you will get (1) credit every month good for any title in their entire premium selection—that means the latest best-seller, the buzziest new release, the hottest celebrity memoir or that bucket list title you’ve been meaning to pick-up. Those titles are yours to keep forever in your Audible library. You will also get full access to their popular Plus Catalog. It’s filled with thousands and thousands of audiobooks, original entertainment, guided fitness and meditation, sleep tracks for better rest and podcasts—including ad-free versions of your favorite shows and exclusive series. All are included with your membership so you can download and stream all you want—no credits needed. And you can seamlessly listen to all of those on any device, picking up where you left off, and as always, new members can try Audible for 30 days, for free, just visit Audible dot com slash isaac or text isaac to 500-500. So we’re into spring and April is underway, and we’ll return next Thursday to the Fermi Paradox series for a long requested topic, a detailed look at Drake’s Equation. Then we’ll shift to look at advanced human civilizations in terms of Longer Lifespans, Post-Humans, Post-Scarcity, and Purpose, before switching back to the Fermi Paradox again to look at how Multiverses alters the equation. If you want alerts when those and other episodes come out, make sure to subscribe to the channel, and if you’d like to help support future episodes, you can donate to us on Patreon, or our website, IsaacArthur.net, which are linked in the episode description below, along with all of our various social media forums where you can get updates and chat with others about the concepts in the episodes and many other futuristic ideas. You can also follow us itunes, Soundcloud, or Spotify to get our audio-only versions of the show. Until next time, thanks for watching, and have a great week! The purpose of a beacon or lighthouse is to show others the way in the darkness, literally and metaphorically. So there’s some troubling implications when we regard the vast ocean of the night and it appears nobody has lit one. So today’s topic is Interstellar Beacons, with a focus on Alien Beacons used to communicate to new civilizations. There’s many good reasons to build a beacon loud enough to be easily heard at interstellar distances, but one of those is to say hello to life in distant places. One of the biggest open questions about our Universe is “where are all the other civilizations?†In a place so enormously vast and ancient, we ought to detect plenty of other civilizations, some of which should be vast and ancient and thus easy to spot. Yet we don’t, and we call this apparent contradiction between expecting to find alien civilizations and their seeming absence, the Fermi Paradox. I do not want to limit our discussion of Beacons today to only the Fermi Paradox, but it’s a major point so we’ll give the paradox a major focus. The purpose of a telescope is to see far away, that’s the literal meaning, while beacon is the opposite: a sign, signal, portent, or lighthouse, a thing meant to be seen far away. In combination, a decent telescope lets one civilization see the beacon of another civilization much farther off. However it only lets them do that if both the beacon and the telescope exist, and the telescope is looking at the beacon. Now ‘see’ is a relative term for telescopes these days, as a lot lot of our farthest seeing ones don’t detect visual light at all, but radio, infrared, and other wavelengths of light not visible to the naked eye. A lot of time with the Fermi Paradox, we emphasize radio communication because we’re looking for a signal, but as we’ve discussed before on this topic, that’s likely a dead end path. The general notion most people are familiar with, and which makes sense on the surface, is that since we broadcast by radio signals, odds are many other civilizations would too, and we can listen in and learn about them. But we are, and have been, all too aware that a signal broadcast on a planet and designed for transmission to a regular antenna on that planet is practically impossible to hear thousands of light years away. We also have to assume anyone elsewhere making a beacon for us to detect knows that too. Now there’s a maximum range you can pick out a signal with a given setup. Signals weaken with the inverse square of distance. So if I have a transmitter that outputs a decent 1 megawatt signal as measured 1 meter from the source, at 2 meters that signal strength will have decreased to only 250 kilowatts. At 1 kilometer out, that decreases to only 1 Watt and the short hop to the moon at 384 thousand kilometers away, drops that signal to only 7 picowatts, which is tiny, and you might be forgiven for assuming we could not detect this. However, even with our current levels of technology, we can actually receive much fainter signals. The Voyager probes are the farthest human made objects and they’re still operating out at the edge of the solar system. Signals from them are being received at a power level of a 10 quadrillionths of a Watt, that’s 10 to the power -16 watts. So while the signal strength is almost unfathomably tiny, we can still acquire the signal, so don’t underestimate the sensitivity we can achieve with a radio receiver. I’d originally planned to examine megatelescopes and beacons in a single episode. It soon became obvious, though, that was too much material to fit into one episode so we’ll visit it in a separate instalment in a couple of weeks. These concepts are very related though. We have lots of reasons to build enormous telescopes, but one is to hunt for life in distant places. As we’ll see in Megatelescopes, we can also hugely boost our reception sensitivity. Irrespective of the sensitivity of whatever massive telescopes we build, there is a hard limit to what we can measure beyond what is called the Cosmological Event Horizon, many billions of light years away. The light and signals from those places will never reach us as space is expanding between distant galaxies and the Cosmological Event Horizon is where that expansion rate reaches the speed of light itself. It’s even a little closer than the Cosmological Event Horizon, because if you are looking at some place where the light traveled 10 billion years to reach us, there’s no realistic chance for anyone to have existed back when those photons left and that’s down to the nature of the early universe. Detection has another problem, though, because noise rises with distance too, as more things can disrupt the signal or overlap it, but you can simply keep making your receiver bigger and your computers scrubbing for noise bigger. If you want to pick up a regular terrestrial signal a million light years away you’d best be getting ready to build telescopes and attached computers that are ridiculously huge even by the standards of this channel. However, that isn’t a concern if you’re listening for an interstellar beacon, which was the low-hanging fruit we hoped to find, not their terrestrial radio. Keep in mind we confused the original pulsars we discovered with radio signals. There was serious speculation they might be alien, and the nearest is nearly 300 light years away, whereas the current furthest is 50 million. I’m not sure how the notion got started that there was a hard limit on radio signal distance but rather than going through the math and physics of that, I’ll just point out we use radio telescopes to get pictures of our universe well beyond a thousand light years out. If you can see a place well enough to make out patterns and details there is a capacity to have sent a message by manipulating those. On this channel we’re no strangers to discussing stellar engineering or moving whole solar systems if we need to, and while it might sound over the top to create an ultra-long distance beacon by moving pulsars around to form a pattern, it is possible. Picking up a star and picking up a terrestrial signal are two very different animals. One is an immense natural phenomenon, and the other is artificial and designed to carry as much data as possible. Raw digital signals have a structure or pattern if you will, a noticeable, non-random sequence. But compression schemes take advantage of that non-randomness to reduce the signal length or pack in more data. The compressed signal ends up looking much more random, what we often call pseudo-random, which is difficult to distinguish from noise and susceptible to noise. Compression also creates the additional puzzle of figuring out an alien compression protocol so we can reverse it. And this all assumes they aren’t attempting to conceal or encrypt those transmissions. So even detecting that there’s actually a signal can be rather hard, even before we get into deciphering and translating it. However, keep in mind you need not crack a transmission to know there is one. Someone might not be able to watch digital broadcast TV from Earth, but they can see a spike in those wavelengths that doesn’t match what they’d expect from natural sources. As we discussed back in Cryptic Aliens, such a planet gives tons of clues off, like spikes based on location and time of day. This is the big difference between a beacon and data transmitter though, the data transmitter sends specific information as fast as practical to a receiver looking for a signal in its broadcast range. The beacon is sending above all else only one message “Look at meâ€, same as a lighthouse or collision beacon on a tall tower. You can then send something more complex on another frequency, say half or double your beacon frequency, or maybe Pi times the beacon frequency if you’re sending Pi, or pause between repetitions to emit chunks of other messages. We could send something more complex paragraph by paragraph, repeating once a day, but with Pi between each paragraph or 128 characters. Since the point is to talk to intelligent life, you can assume basic deductive reasoning on their part. Since the whole point of an interstellar beacon is to be discovered at interstellar distances, you can expect those to be on the frequencies that come through best or which you’d expect people to be watching. The chief example of that is the Hydrogen Line at 1.4 GHz. Except for that sharp hydrogen line, the spectrum band around that is fairly quiet, but much of the Universe is made of hydrogen so our telescopes study that frequency a lot. It’s a safe bet any other young new civilization would too. It's not enough to use the frequency people will look at but also to send something they will easily recognize as artificial, again like the first 256 digits of Pi in binary or prime numbers or perfect squares. This is the key conceptual difference between a beacon and a regular signal, and why it also circumvents common objections to us being able to find them. We can make good educated guesses as to what kind of beacon they would expect aliens to notice, but we do not understand what they might use for mundane communication among themselves. They might use something besides radio signals, which could include faster than light forms of communication, like micro-wormholes that circumvent normal space entirely. We would not send internet traffic to Mars from Earth by omnidirectional broadcast or even a dish, we’d use a laser. Those spread out over distance too but you can use a much weaker and concentrated signal that way. An alien civilization might use point-to-point beamed communication, beam cast rather than broadcast, for the same reasons. Which is another thing, we don’t broadcast that loud. We've worked hard at making better receivers for weaker transmitters since the dawn of radio to save energy, something we still work hard at, so you’d expect signals to get weaker as a civilization advanced. You wouldn’t expect any of that to apply to a beacon though, especially one meant for alien civilizations. Now, that’s not the only reason to build a beacon. Pulsars, natural radio beacons, can be used as a GPS to pinpoint your position and time fairly accurately by triangulating several of them but they only offer so much accuracy. An artificial network, a Galactic GPS if you would, can offer better if you’re willing to build one. It's the same basic concept, some transmitter yells over and over again “I am transmitter 42, the time is 11:08 AMâ€. Though in point of fact they mostly don’t say the time, they transmit a pseudo-random code, which would make them harder to recognize if you don’t know what they are. Nonetheless, it’s quite likely any civilization that does a lot of interstellar travel has giant transmitters set up with each bellowing the time, and time lag on communication is irrelevant in this context since you are specifically trying to tell people the time the transmission left at, so they can calculate the distance to it, and its siblings, and triangulate their precise location. So odds are good the first signal we’d pick up from an alien civilization would be, “I am transmitter 42, the time is 11:08 AM, I am transmitter 42, the time is 11:08 AM and 4 secondsâ€, and so on. Another good candidate would be “3.14159†or rather its binary form, “11.00100 10000†possibly with some strung out explanation of how to build a hyperspace transmitter in between repetitions. Motives for sending the latter could vary a lot, and include pure friendly curiosity, or if humanity is any guide, that message might be “See attached blueprint to make your planet’s own hyperspace communicator, and use Promo Code ‘Vega’ to get 1000 FREE galactic credits to the iGalaxy app storeâ€. And if Nature is any guide, the beacon might just be repeating “This beacon is in our territory, stay out, stay away, mine, keep out, trespassers will be disintegratedâ€. As we discussed in the episode Hidden Aliens, there’s lots of reasons to talk to people, even if you’re xenophobic. Hiding is practically impossible or at least a huge hassle so if you want to be left alone, it’s easier to say “Leave us alone.†We expect that most starfaring species will be curious by nature, or else they wouldn’t have advanced in science and technology. Curious species are likely to send probes and scouts and send even more if one inexplicably disappears. Since controlled aggression is also likely to be a common trait among intelligent civilizations, it also prevents the likely probability of them sending an armada to say a special hello in person after you blew up their scouts without provocation. It’s unlikely any species that’s curious by nature will consider “accidentally and unknowingly walked into your territory, which you in no way identified as yours or told people to stay away from,†a legitimate excuse to blow someone up. As always, we can’t know the minds and behaviors of aliens but we can draw probable inferences from traits we’d expect to be common. If we see it a lot in nature, and it makes sense why it evolved, or the same for civilizations as they progressed, then odds are good it’s common throughout the Universe if not universal. Curiosity is one of those, a desire for survival and security should be another. What kind of beacons a civilization might build all depends on how much energy they have and how cheap it is. I’ll go ahead and say no civilization will worry much about one-millionth of their energy being used to maintain a beacon or positioning clock. I will use a simple real case to create an example. Now I mentioned the Voyager probe earlier, which is 20 billion kilometers away and transmits at 20 watts. That is probably at the outer limits of our present ability to reasonably detect such a signal, so let's run with that signal strength to detect a beacon. Extrapolating a 20 watt transmitter on Voyager at 20 billion kilometers, we will detect a signal at a trillion kilometers out if we use something like the WJR 760 AM 50,000 watt transmitter across the lake from me in Detroit, which is 2500 times louder than Voyager. That’s a distance of a tenth of a light year. Ramp it up further by making it 100 times louder, 5 megawatts, and you can pick it up 1 light year away. This would be louder than any radio tower now in service, our most powerful coming in at about 2 megawatts. To make it as easy to hear a thousand light years away would mean jumping up a million fold on power, up to 5 terawatts. And to receive it 100,000 light years away, across the galaxy, would mean boosting all the way up to 50 petawatts, a bit less than a quarter of all the energy hitting our planet, but almost nothing compared to the output of our Sun. Now at this point most reasonable folks would say Voyager is hard to detect, not something you can pick up on your car radio, and nobody will broadcast at 50 petawatts. However, we said we could reasonably expect a civilization not to mind spending one millionth of their energy budget on a beacon and for a Kardashev 2 civilization, a Dyson Sphere or Swarm, 50 petawatts is not a millionth of their power budget, it’s about a billionth. It’s the equivalent of the US maintaining a beacon that cost about $20,000 a year to run. Such a transmitter could be a statite, basically a glorified solar sail composed of tissue paper thin mesh several thousand kilometers a side that uses the light pressure and solar wind to stay in position. We could set it to transmit an AU above its Sun’s north pole for instance; big but thin, not a hard device to construct in any K2 civilization. That’s not ideal for being heard by 20th century civilizations across the galaxy, but we could be confident they’d eventually point their telescopes in the right direction and hear our signal, and you might say that’s quite enough. The signals already take thousands of years to arrive, and an equal time for a return hello, so you might be fine with using one weak enough it might take them a couple centuries of radio astronomy before they’ve got telescopes big enough to see it and continue surveying long enough to spot it. But I think not because if you are doing an intentional beacon to newly emerging civilizations there’s a good chance you don’t only want to say hello but give some friendly advice too. If you’re worried about potential new friends blowing themselves up when they figure out nukes or how to bulk manufacture anti-matter, you want that warning delivered prior to them having those options. A century or two on the whole means nothing to you, but that specific century or two when they first hear it does, so louder is better, something they can’t possibly miss. If they were going for a millionth of their energy budget, that would be, for our sun specifically, a transmitter blowing away at 400 billion gigawatts. That’s assuming a steady output too rather than pulsing it louder. And mind you, that’s just a Kardashev 2 civilization. An interstellar empire controlling a bubble of a thousand or so light years around their home-world could easily spare an entire star to fuel such a beacon. At this point you are outshining pulsars, and can intentionally mimic them but introduce an artificial pattern, and be confident someone will notice that. You don’t even have to do radio. At the K2+ scale where you’ve enveloped your entire star for power, you can simply have your mirrors, panels, or radiating fins flicker simultaneous patterns in the visible or infrared spectrum, or use modified Shkadov Thruster or Star lifting technology to do the same, turning a whole sun into a literal lighthouse or semaphore. This you probably would not do though as these are white light sources and you can transmit much louder on a single frequency with the same total power instead. The other thing is that on this kind of scale, you need not do an omnidirectional broadcast, or even in a rotating cone, but could send out narrow beams aimed at every single star instead, or every one you thought had a non-infinitesimal chance of having technological life. A narrow spotlight the size of that star’s habitable zone, a weaker and modified form of the Nicoll-Dyson Beam we’ve discussed using for pushing spaceships up to speed or blowing up planets. That’s handy too since it gives you something to do with such beams when not pushing spaceships or blowing up planets. Okay, so that’s the basics of a beacon, let’s ask why you’d build one. Or rather, since there don’t appear to be any, why someone might not. We already mentioned one obvious motive, simple curiosity and a desire to say hello, but that is a lot of energy to spend for a very long time, and someone is bound to point out they could run one, say, a tenth as strong for a tenth the price and be confident a new civilization would find it as they improved their own telescopes and continued their own surveys. After all, those signals may have to travel many thousands of light years, and thus be thousands of years old, before anyone hears them, and just as long back to respond. If you know you can be spotted by a 22nd century civilization with a specific wattage, and a 21st century civilization for ten times as much power, but that the message will still take 5000 years to reach you, that extra investment so you can get a hello back in the year 7018 instead of 7118 might seem a bit pointless. We mentioned another motivation too, the territorial markers. But the point of a territorial marker is to keep people away from your territory, so the goal is for them to see it at your border. Now in spaceship terms this is a little different, because an interstellar ship is committed to a journey once it finishes its initial acceleration, they can't stop when they cross your border so you need to warn them well in advance. Preferably before they leave but at least soon enough so they can find some place you don’t claim or plan to claim to either colonize or refuel at. However you can also rely on them sending unmanned probes first to do flybys and training their telescopes on a prospective colony planet before committing to a mission. So your target broadcast strength for a territorial marker is loud enough they can’t miss it if they are doing common sense preliminary homework, scouting out planets and mapping the places out. Whenever you’re discussing an alien civilization, you are automatically discussing several of them, because if there’s one near us then there’s probably several more inside a sphere of space not much bigger, and likely some them are ancient and not prone to massive expansion. In this context you’re entering a diplomatic realm where the notion of ‘due diligence’ will apply. So you can justify your actions to other civilizations even if you don’t have to justify them to your own people, which you probably will. You and whoever sent such a mission are both playing with blindfolds on so you want to ensure you’ve gone far enough they can’t have missed your territorial beacon unless they were being far more negligent than you were. Regardless, this means your territorial beacons are pretty loud, but not designed to be easily noticed by casual inspection thousands of light years away by a species that is not yet advanced enough to even send an interstellar probe, let alone a colony ship. So we’ve got two reasons to build one, both of which can be argued to be stuff we’d miss now. Ironically, though our half-humorous remark earlier about them sending instructions and some free credits to access the iGalaxy app store provides a better one. Everyone who wants to talk to another civilization has some sort of motive to do so. Maybe you want to be friends, maybe you’re warning them off your turf, maybe you want to sell them stuff, maybe you want them to join your religion or accept your political or economic ideologies. No matter how you cut that, time is a factor. Not just because sooner is better, but because sooner is easier. It’s a lot easier to convince a civilization to be your friends if you phone them with an awesome new technology to solve their problems rather than waiting till they’ve discovered those or accidentally destroyed themselves. “Here’s a device that produces clean, cheap, abundant energy†is a pretty nice housewarming gift for those entering the galactic neighborhood. A xenophobic alien race will find it a lot easier to convince a civilization to stay away from its territory when they are a tiny single planet only dreaming of colonizing the stars rather than one that’s already got fleets out doing so. It’s also a lot easier to convince a commercial civilization to buy your products or subscribe to your services when its way better than anything they’ve got and nobody else is sending them invites. It’s certainly easier to convince folks to join your religion or ideology when you can present yourselves as vastly older and wiser too, and can answer any regular questions or doubts before they’ve even thought of them, let alone locked into an opinion on them. Now the problem here is that while that gives you a great motivation to broadcast very loudly, it might make even more sense to just travel there until we remember the kinds of energies it takes to move a single large spaceship around the galaxy; they are a lot higher than what it would take to send a targeted radio beam at one planet for even millions of years. Similarly sending out a wave of ships to do that to every possible inhabited world is like an omnidirectional broadcast, and more expensive. Also, while we can’t be sure there are no alien beacons out there yet, we can be pretty sure no one is doing open contact missions with Earth right now. A lot of folks think there are little green men running around the planet, but even if they are right, that would seem to imply a different operational profile and motivation from an Alien Beacon, as they are at most likely secretly chatting with our governments, not landing mother ships at the UN and rolling out banners. So this is a tricky one, because it would seem to make sense to have loud beacons, enough that we’d expect many civilizations to choose to do so, and as always with the Fermi Paradox, it’s not about why some civilization would not, or even why most would not, but rather if no one would. I don’t think you can make a strong case that nobody does this, not when there appear many good reasons to do so, and the only bad reason is worrying that it tells people where you live, which as we discussed in Hidden Aliens and will look at more in Megatelescopes, isn’t a good reason at all. On the other hand, there doesn’t seem to be a super-strong case for broadcasting so loud we couldn’t possibly miss the signal nowadays. It’s a weak case, especially in the context of all the other Fermi Paradox issues we’ve raised in other episodes, but not so weak we can just rule it out entirely. That there may be beacons but folks tend to limit their strength to a level they figure no one can detect before they’d be casual spacefarers too. And so while I’d say it isn’t likely, there’s still a chance we might find some beacons in the next couple centuries as our off-planet infrastructure and technology improve. We can start mass producing the kinds of giant telescopes that might hear another planet’s regular radio and we’ll look at those in two weeks in Mega-Telescopes. However before we discuss that, we’ll be looking at the kinds of civilizations that can afford to produce truly enormous telescopes and many other things we discuss on this channel, with an expanded examination of Post Scarcity Civilizations. We’ll be covering that for multiple episodes, and trying to look at some problems civilizations like these might face despite having a seeming abundance of everything. For alerts when those and other episodes come out, make sure to subscribe to the channel. And if you enjoyed this episode, hit the like button and share it with others. And as a reminder, every episode on this channel is available for download as audio-only versions on Soundcloud and iTunes, for those who like tune in while driving. Until next time, thanks for watching, and have a great week! This video is sponsored by CuriosityStream. Get access to my streaming video service, Nebula, when you sign up for CuriosityStream using the link in the description. In Douglas Adams’ famous Hitchhiker’s Guide to the Galaxy series, we are introduced to the Babel Fish, a little fish you could put in your ear that instantly let you understand any language you heard. Sadly, the poor Babel fish, by effectively removing all barriers to communication between different races and cultures, has caused more and bloodier wars than anything else in the history of creation. So today we will be looking at alien languages, what strange forms they might take, and how we might go about decoding and translating them. Those are hard enough when we consider them in the context of classical Sci-Fi and SETI, where we assume humanoid aliens are speaking to us intentionally, sending us radio signals we are technically capable of receiving and intellectually capable of understanding, but things are likely to be much harder in reality. SETI, the Search for Extraterrestrial Intelligence, comes in a lot of forms, but the most well-known is listening for radio signals that look like clear signs of communication, or at least signs of transmissions by intelligent life. It’s biggest weakness, and one of the reasons we don’t spend much time discussing it on the show, is that it assumes alien communications would be readable or at least recognizable to someone other than their intended recipient. The obstacle might not be that the aliens are encrypting their transmission, because it would make reading their signals difficult enough if they were just compressed. Transmitting data is expensive, so it’s in a sender’s interest to limit how much raw data needs to be sent to achieve a successful transfer of information. Let’s use this video as an example, at about 30 minutes long, with 60 frames per second and over a hundred thousand individual images. In its uncompressed form, with about 2 million individual pixels per image, we’d need over 200 billion pixels to be recorded and sent, along with information about the appropriate wavelength of light, and its intensity or brightness. In an uncompressed and simple form, this might well be over a trillion bytes. But rather than raw data, I generally upload my videos at 1080p HD, and about 3 gigabytes each. So that’s a lot of compression. And like any compression, it works fundamentally by taking any pattern and replacing it instead with a note that the pattern exists. So the better you are at data compression, the more parts are left out, and the more your signal looks like noise, making it hard for folks who don’t know the method of compression to recognize they’re seeing a signal at all. But this doesn’t mean a compressed signal looks completely like noise: the goal with compression is not encryption, it’s minimizing data and improving transmission speeds, so we shouldn’t assume that the more advanced a civilization is, the more their signals look like gibberish. No, the objective is to transmit the information with minimum loss or distortion, while minimizing effort needed to pack and unpack the signal. Note that I say effort, because while the objective with a digital signal is to minimize the bits being transmitted, the goal of language in general is the transmission of concepts in a way that least distorts their meaning. Essentially all language is intended to be a form of data compression. This is the critical point about alien languages, that language is a way of relaying compressed concepts, and that compression is part of what might make them so hard to translate while at the same time the universal nature of many of those concepts is what ensures we can translate them, that it isn’t an impossible task. Of course if words are compressed concepts, we can’t know the means of compression, if they have vocal cords and ears for instance, and some of those concepts might be alien. On the other hand, numbers like two, three, and four should be universal concepts regardless of culture or biology and, the notion of adding or multiplying numbers should be universal. Area, volume, density, and essentially all of math and geometry, should be commonly shared, which is why we often think of math as a potential universal language. Logic too should be universal. But it goes beyond that, since physical objects should also be fairly universal. I’m not sure if we can take for granted that an alien mind has a notion for objects and categorization, but it’s difficult to imagine how an advanced intelligence could operate without such concepts. It would be a very alien mind indeed that doesn’t look at an elephant and think, “This is a specific thing, it is very similar to that other thing to its left – another elephant -- and different than that tall skinny leafy thing nearby, a tree, they are all standing on a mostly flat surface, I shall call that the ground, many small objects make that up, rocks and dirt, and far above is a big burning object that moves, I shall call that a sun.†Such a mind would be particularly foreign to us as a species, one that does not classify and categorize or even recognize objects, since we think that way for a reason, and part of that reason is our method of data compression, not just linguistically but in our own thinking. Our brain has to move data around and act on it, so it presumably also has to take patterns and simplify them into a compressed form that works on recognizing those patterns. We can actually see this at work in our psyche, when we see shapes in clouds or faces in an image: it’s essentially our pattern-recognition playing tricks on us. While it works most of the time, we can still see cases where the suggestions of a pattern or concept tell us something that isn’t quite right. On a more complicated level, mental fallacies are also examples of this, where we perceive a pattern or continuation of a pattern that isn’t necessarily there. Somewhere in your head, and my head, is the gooey brain-analogue equivalent of a file titled ‘elephant’, or ‘face’, with a list of what these things are, and how to identify them. There might well be another broad category titled “rockâ€, presumably listing a wide range of attributes that define a rock. But we have to consider that it might not match mine or the next person’s completely. So if I say ‘Can you hand me that rock?’ and point at a brick, some people might instantly grab it, while others might be a bit confused and search near where I pointed for a different nearby object, figuring I didn’t mean “brickâ€, and someone else might ask for clarification, or offer it by saying that a brick is not a rock. Somewhere in our head is a file that says “sunâ€, and that one for sun presumably contains information that the one that appears every day is actually the same one, not a new object. This is something we take for granted, but it really is wired into our association: we don’t have discussions about multiple suns, or measure days in sun-deaths, though if our brain or our cultures did not have this requirement, we might well call our days “sun deaths†or ‘sun births’, and have myths about all the past suns that have come before. And so we might consider that a given alien culture might not think this was the case until they had the technology to investigate their own sun, thinking of it as a new object each time. Object permanence, the notion that objects continue to exist and act or be acted upon even when we do not see or otherwise sense them is a fairly advanced step of cognition in animals and human infants and maybe is not something we could take for granted on alien worlds or in alien minds. Or maybe this would be something that would be a Universal idea even pre-science, as thinking its a new Sun every day because it disappeared over the horizon might be like a child thinking it was a new Mommy who appeared everytime they uncovered their eyes playing peek-a-boo. Given the central and comforting role both the Sun and our parents tend to play in our existence there might be a strong psychological tilt to drawing conclusions that made such central pillars seem stable and eternal. I was going to say that evolution should generally prevent a species becoming culturally and technologically sophisticated if it was insane, and thus things which reduced anxiety like assuming the sun would rise tomorrow might be convergent concepts for that reason alone, however I’m very reluctant to say insanity or anxiety are barriers to civilization, I sometimes suspect they are instead prerequisites. Anyway, we might safely assume some physical concepts like objects, categories, and the fundamentals of physics and chemistry are likely to be universal as well. Whatever they call stars, they should have a distinct word or words for them. They may also put a different boundary on them. For example, a species that evolved on the Moon of a gas giant around a star might place the divide on words like planet and moon, and have gas giants and stars in very different conceptual places. We ourselves changed categories on planets like with reclassifying Pluto, and we did used to thinking of planets as a subcategory of stars, planets simplify meaning those stars that wandered around the night sky, folks didn’t know they were rocks and the stars balls of hydrogen and helium. There are other considerations as well. For instance, they might not have eyes, or might simply be sensitive to light, much as we are to temperature, with a vague feeling for variance and direction. And yet, if we gesture at the Sun and they are able to see that gesture and recognize it as an attempt to indicate an object – both big ifs, admittedly – then there should be a fairly limited number of concepts they think I’m attempting to convey if I then utter a word and they can hear it. Taking all those big “ifs†into account, they’re likely to get that I’m trying to say “That thing in the sky I’m pointing out is called the Sunâ€. They might think I’m saying “Bright objectâ€, and think I mean the general concept which would include a lightbulb, which might be called mini-suns or portable-suns in their language. They might think I’m describing the trait of bright, or the time of day, based on its east and west position, or even the season based on how high it rises at noon based on time of year. They might think I mean the color, or am expressing a warning about radiation, sunburn, or cancer. They might be deaf and think I’m pointing at objects asking them to name them, which they will do by flashing infrared heat patterns on their forehead or blinking their eyelids in a precise pattern. They might be blind and have very good hearing, but have no idea what we’re pointing at. They might have directional hearing that let them know what way I was projecting my voice, so that they could identify the object if I named it while having my head titled that way. And yet in spite of all of that, blind though they are, literally or metaphorically, they can figure out what color is because they can think, and they still conceptualize and categorize. They can know what a photon is in the same way we know about a proton, neutron, or electron. We can’t see those either, though a species that could somehow detect and manipulate them as we do light or sound might “see†those particles in some analogous way to how we see colours, and make images of them. Indeed, we even name the quark forces of color charge red, green, blue, anti-red, anti-green, and anti-blue, even though they have nothing to do with color for us, because we can categorize and conceptualize, and have used those names as an arbitrary system for classification. We just color coded the mysterious force for discussion purposes, letters or directions would have worked too. An alien somehow able to see these color charges, as we call them, but unable to see photons of the visible light spectrum, might detect photons through scientific experimentation and name them after whatever they called the quark force types, in a similarly unrelated and arbitrary way. But translating to or from an alien language might present a significant challenge. On the one hand, we might find all kinds of different lifeforms, and they may not communicate in the convenient, Sci-fi, humanoid way: they may use clicks and buzzing, or colour patterns on their skin, or scents, which may not even be detectable to us, making any form of translation completely impossible without some form of purpose-built technology. If we’re lucky enough to encounter aliens who communicate in a manner similar to us, there are all the questions that come along with any earth-based language, but with all the additional issues of having different references. Coming back to the example of the sun, if we attempted to talk about a “day†with people from a tidally-locked world, we’d likely need to draw on different shared concepts to convey that we mean “a period of roughly 24 hours which we denote by the motion of our home star in the heavensâ€, something for which they may have no independent notion. For us, this idea of “day†crosses cultures and is universally understood, but we’d almost certainly need to discuss it in independent terms. It’s hard to discuss having a ‘rough day’ with a creature from a tidally locked world with no night and day, or one that has no sense of texture for a concept like rough perhaps. A creature adapted to zero-gravity is not going to have euphemisms for ‘getting floored’, ‘being up against the wall’, or a hundred other little ways height and gravity work into our languages. Given that one of the more likely scenarios for meeting aliens would be far ahead in time and deep out in space, it’s quite possible they would no longer be adapted to gravity, or for that matter that we might not be, see our Zero-Gravity Civilizations episode for more on those physical and psychological adaptations. So the reality is that even if a being evolves teeth, tongue, vocal chords, and uses vocalizations to communicate, it may not make use of words in the sense we think of them. Everything could go “right†in the direction of human-like communication and an anthropomorphic form, and we could still end up ‘left’ with a language based on grunts and squeals. On the other hand, they might use sign language, which we also have, and our language is not just spoken words, it is a hodge-podge of facial expressions and gestures and body language too. For that matter our modern languages are hodge-podges of old ones. English is a great example of just how messy things can get, since it incorporates elements and even entire words from Latin, French, old Norse, and several Germanic languages. It has linguistic rules, but they’re riddled with exceptions, and loan-words with no other context in the language are used to fill in contextual voids. In terms of a language having consistency, English is pretty bad. But we still manage to understand what someone is saying, and even if we don’t know the word we can generally guess their intent. We break thoughts up into discrete sections, like sentences, and those have a syntax which we recognize. For instance, we can tell that “John walks the dog†is different from “Dog walks Johnâ€, because of how the sentence is structured: even if we don’t know what “walk†is, we know that it’s an action somehow relating “John†and “the Dogâ€. Similarly the dog wags its tail, the tail does not wag the dog, and this is another example of universality, as it's hard to imagine an alien species would not have an understanding of cause and effect, but be smart enough to actually talk to rather than simply interact with. No technological civilization should be able to exist without understanding cause and effect. When we’re talking about alien language, this is probably our biggest boon. Anyone coming into a language with even a basic understanding of its syntax and a few of the core concepts we discussed earlier--like mathematics, geometry, or chemistry--can probably piece together some simple statements, and use those statements to establish meaningful dialogue about other topics down the road. In essence, we might be able to learn the compression of other languages through certain fundamentals which are universally shared, even if certain localized ideas like ‘sunrise’ aren’t our initial point of reference. On the other hand, translation of an alien language when neither of you already knows the other’s will be a difficult feat, and probably not something we could do without massive amounts of recorders and computers unless we got very lucky about their biology paralleling ours, but it will be possible, because they are smart too. Assuming they are anyway. Folks like to quasi-anthropomorphize animals by saying humans just don’t speak their language but the reality is they haven’t got one, not like ours. My cat might understand another cat better than me principally because it has a very limited set of concepts and it happens to match the other cats, so through simplicity they are able to interpret what the other is expressing. It is not a language, language is a human concept that varies from place to place as an artificial construct of civilizations, but many of them can communicate, even across species, and some can communicate more complex notions. But the lion communicates to the antelope that it wishes to harm or eat it, and this communication is not language. Communication, intentional or otherwise, is presumably the domain of any sentient entity, which is to say something able to perceive or feel things, language is presumably the domain of sapient entities, see our episode “What is Sentience?†for the distinctions between the two but for the moment we will say that language requires much more abstraction. Human language is a very artificial thing learned by each individual human, and uniformity – such as it is – is achieved by a combination of long exposure and usage, and shared biology. Which is to say you grew up around folks who communicated using equipment you also had and who put an effort into encouraging you to do it using the established protocols and terms. In other words babies usually learn the language their parents use, not a different one. You went along with it from a mix of curiosity and need, hence why your first words were generally either attention-getters of naming the caregiver, Mom or Dad, or object identifiers of the thing you wanted, like Ball or Food. For an alien, this same concept is probably applicable, their languages will be built on increasing complexity of shared biology that is well suited for fast information passage. That’s why it probably would not be smells. Humans can smell things, and our sense of smell is much better than we usually assume too, and we certainly can communicate with them in a very rough sense, but it is much slower and less precise than hand gestures, facial expression, glances, and noises which form our main communication method. Humans are not audio-only critters, we can pass information along a lot faster and clearer in face to face communication, but we have as complete a tongue in spoken words as we can, and an even more abstract words-only written form. Written language is hugely compressed but not as compressed as the spoken word, which can carry volume and tone more clearly and quickly for instance. Smell is slow, and same as you have to erase a blackboard when it's full and it leaves a thick blurry layer, a smell based language is going to be a low-bandwidth one because of the time smells take to move, dissipate, and so on. We principally use it in the higher animal world for communications meant to have long dwell times, like territorial scent markings. If you can’t see or hear, then it might have to do. Now could you understand sight or sound if you could only smell? Presumably yes. I doubt that we all have identical concepts for visual objects and categories, where blue ends and green begins probably varies from person to person for instance, but can a blind person know color who has never seen it? Yes, they can, and it might be that they conceptualized it as something akin to the texture the surface of objects has to touch or maybe an analogy to sound, it would vary from person to person, and presumably from alien to alien more so. However, brain-imaging finds that when a sighted person hears a color it triggers the sensory parts of their brain as opposed to the abstract parts triggered when someone hears concepts like ‘justice’ or ‘responsibility’. For a blind person hearing a color will trigger those same areas of abstract thinking, red, green, justice, and responsibility are all abstract not sensory for them. A deaf person cannot hear birdsong, one born deaf can understand it, even if it's in the abstract sense. I cannot see justice, I cannot hear responsibility, I can discuss both, and while trying to discuss a rainbow with a person born blind or a morning birdsong with a deaf one may not be as easy it is with most folks, so too it isn’t easy to discuss them with a person who can see but has never seen a rainbow or heard a birdsong, and pre-modern times we couldn’t just pull up photo or audio recording of either. Which is the other half of the translation issue, sheer quantity of data, but we’ll get to that in a moment. First let’s talk about writing and data storage. An alien might live in a dark environment of thin air where the best means of communication available to them was to rapidly tap their feet so their exoskeleton generated a high tempo beat they could control the tempo on with high precision. This might be their language, but because sound does not linger for days let alone years, unlike smell, at some point they will want a written language, even if the means for writing it is to etch into stone with controlled use of their highly acidic urine or spit. Why? Because writing is not a human concept, writing represents the desire to communicate with someone who is not currently there, and that should be a universal desire. There may be a few exceptions, like giant hive minds or singular intelligences or ones with near perfect recall who really have little need to communicate that way and don’t develop it, but they should be exceptions not the norm. Now writing can be used for other purposes, like a backup memory, where you draw a little cow’s head and mark sticks next to it for each cow that came by that day to keep track of your herd or tax the herders bringing in their cows to trade in your town, or giant squid-monsters I suppose since we’re talking aliens here. You can use this for your memory or as a quick unique language you made with a partner. You probably wouldn’t think you invented a language by telling your fellow herder that you tally sheep and cows and chickens by having empty pepsi, coke, and mountain dew bottles respectively in which you drop pebbles, but in a way you did, and you created a communication method with a specific protocol for data and a compression method. It’s obviously a very crude and limited one but could be expanded upon. We cannot assume an alien watching us gesture at various chickens, cows, and sheep while dropping rocks equal to their numbers in bottles, “One Chicken, two Chicken, one sheep, five sheep, six sheep†and so is going to get the point instantly or right on the nose, but if you do it enough they should. Again, sheer amount of data. We often talk about how we have languages from back in the day where writing was still not too common where we don’t know what it all means, and we use this as an analogy for aliens’ languages being indecipherable, but this is wrong. We can’t translate those old tablets of this or that ancient civilization because we just don’t have much data or uniformity. Some civilization that never invented dictionaries that sprawled over hundreds of towns and hundreds of years but only gave us maybe a thousand words, written by twenty different people each from a different town or time, is not something you can translate with certainty because you don’t know if someone’s shorthand abbreviation or typo with a slightly different way of doing some of the letters is even the same word as in another example, so determining what either or both of them mean is in many ways harder than brute forcing a language written by aliens. Bigger and more technological civilizations will probably standardize meanings of the symbols they are using to record information. More importantly though they will just have an awful lot more of it. They will have a digital way of storing it, because computers are too handy, and I daresay any species naturally talented at math and computation will invent them faster even if they need them less, so they will have digital medium not just analogue. They will find it handy to rapidly send data between places and that means something moving at light speed, and they will probably find things like radio, magnetic tapes, optical discs, semiconductors, and so on are good methods of storing and transmitting data. That means somewhere on their discs or whatever is a definition of a star, of hydrogen, and of fusion. I do not know how many times the word ‘Thursday’ is used in books, or on the internet, or on radio, but I bet it gets used more on radio on Thursdays then on Mondays, and I bet it has been used millions of time if not far more, and I bet it gets used in conjunction with words like day, year, month, 24/7, 9 to 5, am, pm, and so on untold times. An alien hearing our radio is not us looking at a handful of damaged tablets written by different generations using different local lingos and having so little of it that most of their words aren’t used on the tablets even once. See our Cryptic Aliens episode for a walkthrough of how even just listening to radio DJs and analyzing the red-shift of the signals over a day and a year might let you crack a lot of our languages. And a lot of physical concepts are going to just have words recorded in their digital or analogue signals. There is a definition of water, even if might get easily confused with seawater’s word or blood’s or liquid in general. A definition of carbon and lead and iron, all in digital form which if we can recognize it and or they can in ours, can then be rapidly translated. And there’s probably a definition of the word ‘justice’ even if for them its three different notions seen as separate that roughly translate as rules of a game, method or dispute arbitration, and record of execution, or similar. It should be possible for them to die, so they should have a concept for death. It should be possible for one of them to kill another, so their should be a concept for accidental killing and intentional, even if the latter requires such a break with the norm of their psychology that murder is universally considered a type of insanity rather than an act of malice for which one can be guilty. We can consider an alien species which may have no concepts for greed or selfishness, in that same light, and thus might not get theft, but it would seem likely that most if not all alien civilizations will arise around that same dynamic of individual survival and desire in tension with group cooperation, so they are likely to have concepts like murder and theft and thus presumably need words for them. Animals have territory so they can survive, they mark it out as theirs. They do so even though it is warning others you are there and claim it, thus making them on the alert for a possible attack by you, and an unexpected ambush would be more likely to work successfully. However, since neither entity wants to be injured or killed, and that’s a high probability in an encounter, the territorial marking decreases the number of encounters even if by forewarning the rival you increase your odds of losing any given encounter. This logic would seem fairly universal too, thus we would expect aliens to communicate territory to one another in some fashion, and probably in space too rather than hiding from other aliens, as we discussed in Hidden Aliens. This is probably done by radio signal rather than the time-honored traditional method of peeing on things, which is less effective in a vacuum light-years wide. Maybe not, but we know every human civilization will have words for hands and ears and feet and hair because we have these things and will name them. These abstract concepts, territory, justice, love, possession, friendship, and so on may be a lot more universal than hands and tentacles are. Now we can come up with an almost infinite array of ways in which languages might be built, yet we can assume things like radio transmission or optical or magnetic storage because of how universal physical laws are and how efficient such things are at the purpose. In this same way we should not assume any given alien is going to concoct a complex language utilizing a method their biology allows just for the novelty of it… though they may have limited versions of their language exactly for that. Possibly for novelty of course but because it might have niche uses. We have sign language even though we use spoken word as our principal communicator and gestures, facial expressions and so on as supplementary methods, sign language is handy for communicating at close range with line of sight when silence is desired for instance. This means they too are likely to have niche alternative means of speaking, and thus understand that some other creature might use a method they do not, but it is likely to be a method that makes sense for the environment or the goal of fast and accurate concept relaying. So a careful use of a colored flag lifted in a specific pattern of directions and speeds, for instance, is generally not convenient, so we would not expect it to be a main language conveyor, though its one humanity has often used. Smell travels slow, carefully filling glasses with water to different heights and ringing them to create a pattern of sounds and tones is a major pain in the butt, so we wouldn’t expect someone to do that, but one could imagine a species whose biology was so arranged. A spider could weave a web that said something, like with Charlotte’s Web, but that’s not going to be too convenient usually. Again we can imagine a vast array but we can probably guess what an alien might use by just knowing their biology, if the creature has no vocal cords or lips because its lungs for air and mouth for food don’t share the same throat and orifice, but it has some big biological drum built into it that it regularly whacks and seems to emit repeating timed patterns, then you can probably bet that’s part of what it uses for talking. Though someone watching our lungs might falsely assume our rate of breathing was how we communicated, some pattern of breath or heart rate. It’s entirely possible it has a complex series of shoulder shrugs or toe wiggles that are part of the process, or how it puts its feet, and while we’re trying figure out what it means with its hand gestures, which mean nothing, its ignoring us point our fingers at things and trying to figure out what our toes or shoulders are saying, which is mostly nothing. We do communicate with how we set our shoulders, but we only use them in a limited way as part of our language, a shrug of the shoulders can state uncertainty on a matter, but we do not use them as a letter or word-sound. Fast breathing can communicate distress, fear, desire, etc but is not used for relaying words or letters either. The other trick we might have for determining how they talk is by looking at how they listen, because odds are any natural language has a limited range of accuracy that makes the critters using it focus on whoever is speaking, so to speak. We don’t have to look at someone to understand them but it helps us guess what was said when it’s a bit unclear. Having had a speech impediment my whole life, even after a lot of speech therapy in recent years, I still habitually tend to look right at people when speaking to them, and more so if they’ve indicated in some fashion they had problems understanding me, to make it easier for them to read my face, lips, and so on. We can probably assume a lot of aliens would be turning their sensory organs toward the communicator and start guessing by which are used and when, what the various main and secondary means of communication are. Ultimately after that it’s all about collecting a lot of data and examples, and analyzing their frequency and pattern, and if you can interact with them directly, not just by distant and slow radio, by assuming that if they are staying near you and not trying to flee or kill you, that they are also observing and that they will probably be trying to do what you’re doing, which is figuring out how to communicate and assuming the other person is too. So it might need a long time to figure out that us lining one on our limbs up in a various directions and exhaling in patterns was us pointing at an object and giving the auditory vibrational pattern to identify it, and we might need a long time to realize it was spitting on an object to indicate it was naming it while spitting halfway between it and us to indicate it wished us to name it, all while do that naming by a rapid and precise blinking of twenty eyelids. But with enough intelligence, recording equipment, computers, and most of all, a desire to communicate and patience, it will get figured out. Differences in languages can make our fellow humans seem very alien to us, and yet in the end the fundamental purpose of languages, to share often abstract but universal ideas, is what makes each of us less alien to each other and what might make aliens seem much less alien to us. So we ran fairly long today for an alien civilization series episode, and I ended up cutting out a discussion of what the common medium might be for transmission to say hello, like how we might send a signal with the intent of it being noticed or vice-versa. That makes it a great chance for an extended version on Nebula, and for those watching on Nebula rather Youtube you can see that extended version in place of our usual sponsor spot. Nebula is our rapidly-growing streaming service where you can see all of our episodes ad and sponsor free and a couple days early, as well as some bonus content like our extended editions or Nebula Exclusives like our Coexistence with Alien series. You can also see tons of content from many other amazing creators and help support this show while you’re at it. Now you can subscribe to Nebula all by itself but we have partnered up with CuriosityStream, the home of thousands of great educational videos, to offer Nebula for free as a bonus if you sign up for CuriosityStream using the link in our episode description. That let’s see content like Stephen Hawking’s “Are we Aloneâ€, and hear the late great genius discuss his thoughts on Alien life. So this means you can watch all the amazing content on Curiositystream, but also all the great content over on Nebula from myself and many others. And you can get all that for less than $15 by using the link in the episode’s description. So that will wrap us up for today but we have our mid-month Scifi Sundays episode on Laser Pistols, Lightsabers, and other scifi weapons coming up this weekend. After that we’ll be discuss Arcologies, giant buildings containing whole communities and ecologies and how to design them, before wrapping up our May episodes with Solar Flares and their impact on the Fermi Paradox. Then Closing May out with our Monthly Livestream Q&A on Sunday, May 30th, hopefully from our new studio. If you want alerts when those and other episodes come out, make sure to subscribe to the channel, and if you’d like to help support future episodes, you can donate to us on Patreon, or our website, IsaacArthur.net, which are linked in the episode description below, along with all of our various social media forums where you can get updates and chat with others about the concepts in the episodes and many other futuristic ideas. You can also follow us itunes, Soundcloud, or Spotify to get our audio-only versions of the show. Until next time, thanks for watching, and have a great week! This episode is sponsored by Brilliant It’s our great hope and goal to get out into the galaxy and meet its other occupants if they exist, but what if it turns out the galaxy is empty because they packed up and went somewhere better? So today we’re back in the Alien Civilizations series to take a look at the notion of advanced civilizations transitioning beyond a physical existence or even to another reality. This is a bit of a continuation of last week’s Fermi Paradox Extinction episode and a popular solution for the Fermi Paradox. The Fermi Paradox being the big question of why our Universe, as such a vast and ancient place, seems devoid of any vast and ancient civilizations. Solutions inevitably revolve around the idea that something just makes these civilizations almost never come into existence, stay small or hidden, or go extinct. These all have some element of pessimism to them, and makes the Universe, or the process of evolution, seem a much colder place or harsher process than we’d prefer to view them. A more cheerful notion is that advanced civilizations are much more common, but that they prosper and grow to a point where they just don’t need to obey the laws of the Universe as we know them or play Darwin’s harsh game anymore, they’ve found something better and more enlightened. Which implies we could too if we play our cards right. So it’s a popular theme of a lot of science fiction and truth be told, long predates the genre. Many a mythology, theology, or ideology both past and present has offered up some better place beyond, the Sacred World, as opposed to material world around us, referred to as the Profane World, though the term profane has mutated a bit in modern usage. Needless to say, if such places exist, many folks would understandably want to leave behind the Profane World to travel or ascend to that Sacred World. One recurring theme we have in the Alien Civilizations series, that makes it distinct from our Fermi Paradox episodes, is that we often approach concepts more from a motivation standpoint rather than just means and opportunity for figuring out how an alien civilization might act. An alien civilization with interstellar ships obviously has the means and opportunity to visit or invade Earth, so we ask what their motivations would be to do so and what actions, in light of such motivations and capabilities, would make sense, then we ask if we can see those as supporting evidence they might exist. You’ve a very simple and easy motivation to seek to ascend from the Profane World to the Sacred World for instance, if it exists and can be ascended to, many civilizations will seek to do just that. Of course that doesn’t mean they all will or that every member of it will want to, even assuming they can, as it’s often implied to be a place or state that has more to do with the mind and ethics of the individual. Plus, it’s very poorly defined, or maybe it would be better to say it has too many definitions. Nobody’s ideas of enlightenment and utopia tend to match up too well, let alone different species with completely different evolutionary origins, motivations, and biology. On top of this, you’d have the issue of those who were ultra-evolved and enlightened versus those who merely think they are, which is also of course rather subjective, and many examples in science fiction come off this way, seeming far more smug and aloof than seems merited. This is only the beginning of the problems with the general notion we need to look at, a couple of which aren’t problems with the concept so much as using it as a Fermi Paradox solution. Though as we’ve noted before, just because some behavior or concept doesn’t make for a good Fermi Paradox solution doesn’t mean nobody does it, and in the series we try to look at those hypothetical civilizations regardless of if they make good Fermi Paradox Solutions, even if sometimes it is just to conclude why such civilizations probably aren’t very common. The point of Fermi Paradox solutions is to explain an absence of observable alien civilizations. The Ascension approach only works in that regard if it’s a one-way trip that prevents you from poking around this universe anymore by rule or inclination. In science fiction these entities usually aren’t allowed or inclined to involve themselves with us and our petty mortal concerns, and for good reason, it really wrecks stories when you’ve got super-powerful entities hanging around who intervene all the time, saving the heroes rather than allowing them to save themselves through wit, luck, and perseverance. Of course, life is not a story – probably – and stories that feature such entities usually need to cobble together some rationale, often poorly written, for their actions. After all, the presence of some enlightened, super powerful being or beings that transcends reality begs the question as to why they’re not constantly helping or crushing our normal, mortal, and relatable heroes, depending on if they’re benevolent or malevolent. If those stories get sequels or become a series the original rationale for why that behavior made sense gets thinner and thinner as the audience contemplates them. Q from the Star Trek series is a great example, depending on the writer he can be comic relief, sinister villain, or even hidden friend and mentor, it’s only John de Lancie’s superb acting that saves the character. Tricksters make for good ultra-powerful characters in storytelling, you expect their actions to be confusing, often cruel, and not having much point other than for their own amusement, and it makes a bit of sense that they can’t go too far because they have peers who only tolerate so much mischief. That they tolerate any gets handwaved away to being aloof, they don’t really care that much about lesser beings and our petty problems, but we’ve got a problem there too. We have a megastructure we discuss a lot on the show called a Matrioshka Brain, essentially a massive supercomputer or mind that uses an entire star to power its thinking, and since that’s a lot of thinking, it’s probably rapidly maxed out the efficiency of computer chips, so it not only is running on a trillion, trillion times more power than whatever device you’re watching or listening to this episode on, or that your brain uses, it’s probably doing so with orders of magnitude more efficiency too. This isn’t necessarily a conscious mind, and isn’t necessarily limited to one mind. This is one option for ascension under known science we’ll discuss in a bit, but if it were a conscious mind, that thing would have so much processing power available that it could literally simulate every human that’s ever existed simultaneously without even putting a tiny dent in its total processing power, and could even more easily carry on simultaneous conversations with everyone living on Earth, or indeed on every planet in the known Universe, even if every single star had a planet with a human-level species on it. It’s just that terrifyingly high-powered, and a little more terrifying because that construct requires no higher technology than we have now. Like any Dyson Swarm or Stellar Engine, while more technology helps, it’s simply a matter of brute force construction, all you need to build one is a single robot capable of mining resources in space and making copies of itself and following some basic construction. Something we’ll probably have this century or even this next generation. Such a thing might genuinely not care about what the rest of us are doing, but if it does care, even just a little bit, it really could micromanage every single one of our lives constantly with no more proportional effort than throwing some spare change into a donation bucket. So it doesn’t matter if it cares about us just a little or an awful lot, the effort involved is just so microscopically tiny. Not a new concept of course, a regular commentary on God, the Demiurge version that is a creator of an entire vast Universe, is that the creator doesn’t care much about all the little details. But not from a lack of capacity, which is presumably way higher than even a Matrioshka Brain, which again would barely even notice the processing power used up if every single human called it up for advice on every little problem bugging them. Again it might not care, or may prefer a pretty hands off approach for ethical reasons. Relative Intelligence isn’t a good reason for not caring of course, you can make a strong argument that being smarter makes you more curious and interested in all the little details, as you can track them all and see their importance easier and understand them better. As we’ve noted elsewhere, humans are much smarter than insects but we still have an interest in them and many folks make a career of it. Similarly, while we are often quite fond of cute cuddly critters, we’ll often take a hands off approach to them in the wild, even when we’d like to help. That’s a fairly common theme for explaining non-intervention by such ascended entities too, they don’t want to interfere with the natural progression of those below them. I should note though, that we will often interfere to stop extinction, and they too might tend to have a red line where they felt compelled to act. Quite a pain from a storytelling perspective, since you can only show such entities when they are breaking the rules and feeding the wildlife, like how we often see with the Ancients in the Stargate Franchise, but not a problem in the real world, since they can exist whether we notice them or not. It removes them from the galactic chessboard, which is handy for storytelling but not very realistic, as if they’re off the board at all, it’s probably merely because they’re the chessmasters moving all the pieces. However, if they care and have the capacity to get involved, you need a reason why they aren’t. “We have rules against it†is one, but requires an explanation of what those rules are, why they matter, why the line between acting and not acting is what it is and isn’t arbitrary, and how it’s enforced and arbitrated. An alternative but parallel notion is that ascension doesn’t necessitate benevolence, and that there is some equal but opposite malevolence. Ahriman from Persian mythology or Zoroastrianism would be an example of the equal and opposite evil God we see in dualistic cosmologies. From Stargate, we eventually get introduced to the Ori, the evil opposites of the Ancients, both from a long dead civilization where everybody either ascended or died off, and presumably created to deal with the apparent plothole of ultra-powerful benevolent entities who rarely helped the heroes out, or possibly because the show was in its ninth season and desperately in need of new villains. The original bad guys, the Goa’uld, had undergone what is often called ‘villain decay’, a common problem of recurring bad guys who, while being way more powerful than the heroes, are repeatedly beaten until they aren’t scary or menacing to the audience anymore. Q from Star Trek often came off that way too, as did the Borg, and countless other villains in other series over the years. Indeed one of the ways of rescuing such bad guys from audience indifference is to flip them over to the good guys side as antiheroes or teaming up with them against some greater enemy. They did that with both the Goa’uld and the Borg, and it gets done with a lot of comic book characters, folks like Magneto or Doctor Doom, or even Thanos or Galactus, eater of worlds. You flush them out as characters and make them either more sympathetic or understandable, not just mustache-twirlers. Mustache-twirlers make for bad villains in stories, largely because they don’t seem realistic, a villain has a motive for what they do, don’t usually regard themselves as villains, and except for the mischievous trickster don’t do bad stuff for their own amusement, but rather because they viewed it as a necessary evil. This leads folks to ask why they didn’t do something else instead, using Thanos as an example, instead of wishing away half the population of the Universe with the Infinity Gauntlet, why not just wish for twice as many worlds, or even an alteration to everyone’s biology or psychology to achieve his goal. Big bad guys with murky but evil goals raise the question of why they want to do that, and if you turn them into semi-sympathetic big bad guys doing what they consider necessary evils, it begs the question of why the big bad guy can’t see the obvious flaws or alternative paths. Of course the exact opposite tends to happen with mysterious but benevolent entities in such stories too, they sit on the sidelines not helping and start coming off as aloof, powerless, or just jerks. There’s entire pages over on TV Tropes arguing the cases for and against this or that ancient and powerful species being either benevolent, neglectful, or abusive prescursor civilizations. And I’m focusing on all these fictional examples because it’s only in this long-running series format that we start noticing the holes in a lot of the behavior and motivations of such ascended critters, Benevolent or Malevolent. We looked at examples like Cthulu style ancient and terrifying entities in our Sleeping Giants episode and you tend to get the same problems, which are fine in fiction, until the audience starts noticing the flaws by their constant recurrence, but don’t really make sense in real-world contemplation. Just as an example, that hypothetical Matrioshka Brain we were mentioning earlier, could quite easily take copies of everybody’s brain and upload them on their death to some virtual paradise. At first that sounds like an entirely fine approach to non-intervention, as it lets you live your own life and grow spiritually and so on, and no matter how bad things go, it rescues you afterwards to paradise. That’s fairly parallel to Irenaean Theodicy from back in the 2nd century AD, though not a perfect match since classic philosophy or theology on the Problem of Evil generally only apply if you’re dealing with an entity that is specifically infinite. A Matrioshka Brain is not, and its hypothetical simulated paradise, its Sacred World, is actually beneath and contained within the material Profane World it draws on for resources. It’s arguable if its ascended anywhere at all, and indeed you get a reverse case in simulations, since it might create entire new races of folks living in virtual paradise who, if they ascended from there to the higher reality – our universe where the computers run, they are instead ascending from the Sacred World to the Profane and might be rather disappointed in it and want to go back. Which could happen in our cases too, maybe we can access other hypothetical Universes above our own, higher realities, or just parallel realities in a Multiverse. You might head off to these and decide they aren’t all they were cracked up to be and want to come back. That raises another issue, which is one way trips, which are problematic for many reasons. It could be that a species might find a way to go to some newer younger universe, devoid of life, full of resources, and low on entropy. You open a gateway there, or even create this new Universe, and have all your people jump on through, escaping both the inevitable Entropic Death of the Universe and having to compete with any other folks. This idea’s got some big problems. First, if it is one way, how the heck did you ever get a report back from there confirming it’s a ripe plum waiting to be picked? And if you haven’t got that proof, how are you convincing folks to jump on through? Every single one of them needs to make a rather literal leap of faith. It would be completely reasonable and inevitable that some wouldn’t. On the flipside, if it is a two way street, there’s nothing stopping you from coming back for visits or just importing resources from there. You ought to be able to construct an entropy-violating engine using that too, giving you an infinite power source. Indeed in Iain M. Banks Culture Series, our Books of the Month, they draw on just such an approach for powering their starships, reaching into what they call the Grid for their energy, and this Grid also blocks them from Inter-Universal Travel, kind of like the Earth’s Mantle in a way, great power source but hard to pass through, and its implied that more advanced civilizations eventually figure out how and jump into new universes on the other side of the Grid to explore them or just avoid entropy. Ascension is a great way in a story to clear the setting of pesky elder races who’ve been around for millions or even billions of years and ought to have colonized everything themselves already, or at least play king of the hill and tell everyone else what the rules are and how things will go. It does always require asking two questions though. First, why don’t they help others do the same, just leaving instructions behind on how to build the Ascend-o-Matic or gateway to their own personal universe? And if it’s greed to keep all the resources to themselves, why aren’t they keeping this Universe in their pocket too or leaving behind automated armadas to purge the Universe of any potential future competitors that might follow them? Second, what happened to everyone who didn’t go? A lot of authors just skip this point entirely, which is one heck of a handwave, points to Peter F. Hamilton in his Commonwealth Saga for noting that problem. Not everyone is going to be into ascension, especially if it requires a leap of faith, and those folks left over shouldn’t just disappear. Though even there his example, the Anomine, who mostly ascended after a period of playing Guardians of the Galaxy, left behind a remnant who was just focused on living a primitive life. Some other authors have done that too but in this case the remnant wasn’t ignorant of what their transcended ancestors had done, nor did those other folks clean up all their high tech artifacts, they just didn’t want to do it themselves. The flaw is that they were strangely binary in their approach, transcend or sit on their homeworld farming. One could argue that almost everyone of an explorer mindset jumped in the Ascend-o-Matic, but even if we assumed nobody left behind felt like further exploring, colonizing, or policing the galaxy at that time, why in the heck didn’t a single member of a following generation? It is a great book series by the way, another of our books of the month, but like many a story it’s got some weakness on examination. As I’ve mentioned, that’s pretty much unavoidable if you want to tell a story in a galaxy full of ancient civilizations of powerful entities and still have your main characters be human and relatable yet somehow relevant and capable of dealing with galactic crises. This is a recurring issue with a lot of Fermi Paradox solutions, they emerge out of science fiction or get popularized there and the author does a great job making it sound plausible. In reality, some advanced civilization that leaves a remnant behind is either going to watch over that remnant, leave something behind for any to follow who want to, or just abandon them entirely. If that last, then a few generations later you’ll have a whole new crew of folks wanting to go out and explore and build, probably aided by all the junk and libraries their ancestors left behind, not to mention likely being very evolved or genetically enhanced or similar, giving them a headstart to repeat the process. Even if that just resulted in recurring waves of settlement then ascension, that is very much not an absence from the galactic scene. If they do leave behind the Ascend-o-matic or portals to new ripe Universes, why aren’t they also leaving those for other civilizations too? I suppose they might be really racist, but we usually assume they’re pretty enlightened. Of course they don’t have to be, and I did mention the Ancients and the Ori from Stargate earlier and how everybody either ascended or died off and the Ori were jerks. It’s entirely plausible some scenarios for this might involve ideological wars where the pro-ascension faction, or factions, wiped out the remnants on accident or on purpose. But if they’re interstellar that almost has to be on purpose, since even if the Ascend-o-matic had the unintended consequences of vaporizing worlds or entire solar systems, you presumably don’t flip them on in every single colony at the same time. You’d also expect any grand war between such factions to have unaligned refugees fleeing to new space and there’s no reason to assume they are going to opt for techno-primitivism, and do that forever, or have the exact same argument about ascension on their worlds just a few generations later. Now a big caveat to that is assuming they’re actually interstellar when all this happens. Our nominal ascension-on-the-cheap method of dumping everyone into a simulation in a Matrioshka Brain for instance doesn’t actually require interstellar flight. It doesn’t even require a fully assembled Matrioshka, with its many trillions of trillions of times more processing power than a human brain, which is probably going to be overkill for solving almost any scientific problems we still have yet to crack. As I mentioned, that isn’t an object that requires you already be an ancient galaxy spanning civilization to make, and while the power levels available to such a construct are far more than sufficient to let you engage in interstellar travel, even ignoring all the new technology such levels of computation and mind simulation probably are discovering, you might easily have such a thing assembled in its entirety before your ships have reached all but the closest worlds. Indeed, even its tiny early version when you first begin construction is likely enough. It’s entirely possible we’d have computers on Earth quite capable of emulating human minds, maybe all of them, before we ever had the first person born on another world, even just Mars or the Moon. Or computers powerful enough to solve some formula for popping open gateways to new universes, so nobody has an interest in spending centuries on some tin can creeping toward another star. I still can’t see us abandoning our presence in this Universe, not even if these new places offered an infinite buffet of resources and excitement, some folks would remain, even if just to guard the gateway maybe, and if not, if we needed leave no gate, then we need fear no alien invasion behind us, and might as well use some of the now redundant resources of this solar system to let any such critters know how to do as we did. Same basic reasoning there as why you don’t invade a primitive planet messing up its own ecosystem, you just send them the plans for devices that let them avoid doing that, or send them a volley of relativistic kill missiles, which obviously won’t help the environmental problems much, but if you’re that much of a smug and aloof species which won’t help even when you easily can, genocidal tendencies wouldn’t be too surprising either. That is the problem with Aloof Aliens in general, be they ascended to higher planes of existence or just ultra-powerful, we can handwave at non-intervention approaches initially but the more one thinks on it, the less it really makes sense as an ethical policy or one you could actually enforce. See the Smug Aliens episode for more on that, but the abandonment for better places, regardless of if you leave a remnant behind who doesn’t want to come or to show others how to go, it has the question of what’s actually making these places better? I mean sure a lower entropy universe is just handy, but only for power and resources, so you only migrate if it’s a one way trip, otherwise you just go there to colonize, same as colonizing new worlds here, and setup trade. Now it could be stuff like dimensions where the speed of light was way higher, allowing faster travel, or weirder stuff like places with 4 physical dimensions or types of matter and energy we don’t have here, or entirely new things comparable to those that don’t exist here, but that doesn’t seem to offer a case for total abandonment of our Universe, and we’ll explore higher-dimensional aliens another time. Of course we don’t even know if such places exist, let alone how to travel to them, and nobody is sending us invitations or directions for a visit. So for now, we’re stuck in our Universe, but it’s a pretty awesome place still full of wonders and mysteries to explore, so there’s no big rush. Speaking of all those awesome wonders and mysteries in our Universe, and exploring them, while we can’t send ships out yet to take a firsthand look, we have been learning more and more every year and if you’re interested in exploring the universe and how it works from the comfort of your own home and at your own pace, try out Brilliant. Their online interactive math, science, and computer science courses and daily challenges let you enhance your knowledge of math and science with easy to learn interactive methods. To make it even easier, Brilliant now lets you download any of their dozens of interactive courses through the mobile app, and you'll be able to solve fascinating problems in math, science, and computer science no matter where you are, or how spotty your internet connection. If you’d like to learn more science, math, and computer science, go to brilliant.org/IsaacArthur and sign up for free. And also, the first 200 people that go to that link will get 20% off the annual Premium subscription, so you can solve all the daily challenges in the archives and access dozens of problem solving courses. So we were talking about exploring strange new wonders and worlds in our Universe, and beyond, and many of those are potentially hostile places, indeed almost everything off this planet is. Space is often described as a vast empty place but it’s not empty, it’s full of lots of radiation and dangerous hypervelocity micrometeors. Next week we’ll be exploring the spacesuits of the future, from the near term to the really high-tech, including ones that might let you dive down into gas giants or walk around on the surface of molten hot worlds like Venus. The week after that, we’ll look at how to cool Venus down and terraform it, in Winter on Venus. For alerts when those and other episodes come out, make sure to subscribe to the channel and hit the notifications bell. And if you enjoyed this episode, hit the like button and share it with others. And if you want to join in on the discussion of this topic or any of our others, leave a comment below or join our Facebook, Discord, or Reddit groups, Science and Futurism with Isaac Arthur, or head over to the website, IsaacArthur.net, and check out our forums, and all of those are linked in episode description below. Until next time, thanks for watching, and have a Great Week! We often speculate about what would happen if an alien civilization visited us, but what if one already has? So today our main topic is the idea that ancient alien civilizations might have visited us, and influenced our civilization at some point in the past. This is a bit of tricky topic because on the one hand, we have tons of really half-baked examples in this category of Fermi Paradox Solutions, while on the other, it’s actually one of the logically stronger examples. The Fermi Paradox, the seeming contradiction between the ancient immensity of the Universe and how we seem to be it's only inhabitants, has tons of proposed solutions. Here at SFIA we generally break them down into 4 main categories. The first is that intelligent technological life just emerges far less often than we tend to assume or doesn’t last long, the second is that it’s common enough but we just aren’t seeing it, and the third is that it is common and we do see it, but we just don’t recognize it or believe the evidence. The fourth is our miscellaneous category for those that overlap two categories or don’t fit in. Now we walked through all of these and their subcategories in the Fermi Paradox Compendium, and there are a lot, even by just giving a passing look at them that episode still clocks in at over 70 minutes, our longest episode, and the second longest is the original version of that episode. It would probably be beneficial to have seen at least one of those before watching this, though I will recap major points. Over the last couple years we’ve tried to give most of the major solutions their own episode and indeed category 1, that civilizations are rare, has its own series here, the Great Filters, which in fact only covers part of that category. And to a degree so does Category 2, that we’re not seeing them, in the somewhat tongue-in-cheek Alien Civilization Series. However we tend to skip over category 3 a lot, and that’s mostly because it’s awkward. The basic theories are actually entirely fine, and as reminder those subcategories are: 3A – Aliens are here but in secret 3B – Aliens visited our ancestors, our main focus for today 3C – Aliens are here but we can’t tell And 3D – We are actually aliens. There is a lot of overlap in these categories too, but 3A, that they are secretly among us, differs from 3C, that they are here but we can’t tell, in that 3C isn’t implying any attempt at hiding or deception, or even necessarily that they aren’t from Earth, a sentient rock or tree or cloud we just don’t even recognize as having a mind would be an example, or critters not from space but from some semi-overlapping parallel reality. 3A on the other hand is our UFOs and little green men category. Alternatively 3B, Ancient Aliens, is not exclusive of 3D, that we are aliens, since we might be a left over colony. That was a fairly popular theory back before we had a solid understanding of DNA and a complete enough fossil record to show that all life here almost certainly has common descent to something billions of years back. You can’t be a descendant of the aliens of Tau Ceti because we can show that not only are you and I distantly related to our cats and dogs, but they can’t be from Tau Ceti either because we can track fossils back to show that common ancestor was here. Of course it doesn’t exclude an alien colony setting up shop here billions of years ago, but then they either must have left uncolonized, some stopped in just to plant a flag and sneezed, leaving only a couple bacteria behind, or having been wiped out so spectacularly that only microorganisms survived. It also still leaves the door open to panspermia, the notion that the first life on Earth might have arisen not from tidal pools or oceanic thermal vents but from comet impacts where the comets housed bacteria or at least chemical building blocks for bacteria. One of the things we would like to do when going to other places in our solar system is to look for evidence of life. If we find life in those places and it is made of the same building blocks as life here, like using DNA, RNA and amino acids to make proteins then that will strongly support panspermia. Recently in 2016, the team behind the Rosetta comet landing mission reported that they had discovered the simplest of the amino acids. Earth organisms use glycine. In the dust surrounding the comet 67P we also found glycine. This was a confirmation of the first detection of glycine found during NASA’s Stardust mission that flew by Comet Wild 2 in 2004. Now, before we get all excited about panspermia, we did not discover other amino acids we use and, unlike other amino acids, glycine is the only one that has been shown to be able to form without liquid water. So, this might be nothing more than a molecule that occurs in the mixture of organic molecules we find in and around comets. One amino acid, an organism does not make. Even so, we do not have a very clear picture of how life initially arises from inanimate material, called abiogenesis, beyond that it should rather obviously require a decently rich soup of appropriate chemicals and an energy input. So all our theories on that are just looking for places where that occurs and trying to guess how common they were on the early planet and which might have been the more probable life-bearing soup. The only two problems with the notion that we might be transplants from another planet are that first, it just moves the origin issue back, to an even more distant time and location, and second you need a transport mechanism. Whether that’s intelligent or natural, it leaves a big question mark as to why the galaxy isn’t teeming with life. Which, of course, is the whole problem with the Fermi Paradox in the first place. It’s not a very good Fermi Paradox solution if it just leaves you with the same problem. The Fermi Paradox is presumably not a real paradox, folks leave comments about that sometimes so I feel obliged to state the obvious, we assume there’s an entirely logical solution that would make it non-paradoxical. Most solutions proposed do not do a great job at that, and many just pass the buck, but some actually exacerbate it. We try to look at the problem from the perspective of known science and technologies that are reasonably plausible under that science. Folks will often suggest some science or tech that would seem to solve the problem, after all we are very new to science and new theories are abundant, but most actually make it worse. Faster than Light Travel, time travel, travel to parallel universes, technologies that can create or convert energy even better than fusion or antimatter, or thermodynamics bending technology like a perpetual motion machine all make exploring, traveling, and colonizing the galaxy easier, which does not help with the Fermi Paradox. If you assume civilizations have warp speed travel then the option that they haven’t colonized the galaxy relies entirely on a matter of preference, and extinction becomes ludicrous, they will have had some remnant or distant isolationist colony survive anything that brought them down, and on astronomical timelines even a handful of folks can breed back up a galactic civilization. This is a big problem for everything in our category 2 and 3, and most of the miscellaneous ones in 4 as well, but it’s especially lethal for 3D, the idea that we’re descendants of aliens. 3C, that we can’t recognize them as intelligent, smart clouds or rocks or trees, suffers from other problems we discussed in the Compendium, mostly 1 big problem for the theory and 1 big problem in discussing it. The problem with the theory is that, in a nutshell, intelligence can recognize other intelligence. Assuming your intelligence evolved, it did so because it served a practical purpose in aiding your survival, which for higher intelligence means having tools and altering your environment, you don’t really need a high-abstraction thought process for quick dodging of predators, indeed it actually tends to hinder that as we’ve discussed before, conscious thought can slow you down. The kind of intelligence that would tend to lead to civilizations and technology are the kind that form a group to spot wolves to defend against them or hunt them instead. Those tools and alterations are noticeable and easily recognized as artificial on the whole. The other problem, in us discussing it, is that you can’t really prove or disprove it. I don’t know how to disprove that a rock is intelligent or that there’s a parallel Earth, like some fey realm of fairies and leprechauns, that we can’t detect. Same as the Simulation Argument or the notion that reality might be a dream, you can’t prove or disprove it, so discussing it tends to be fairly futile. Falsifiability is important in theories, not just for good science, but because generally that which can’t be falsified or proven typically has no obvious bearing on our existence anyway. That leaves us 3A, aliens among us now, and 3C, aliens among us way back. Needless to say both could be true, they aren’t exclusive. And for that matter, while I don’t give it a category, these sub-categories exist under the assumption that there aren’t aliens hanging around openly and publicly on Earth anyway. That’s sort of the point of the paradox in the first place, but we can’t actually rule out that you and I might simply be insane, that your neighbor has green skin, has a UFO in their driveway, is not from Jupiter, Florida but the actual planet, makes no secret of this, and you just filter it out. Considering lots of people seem to do this with other things, that we do tend to accuse folks who follow category 3A of being unhinged is probably rather unfair. Many of the other solutions require either us or the aliens to have some behaviors that might be viewed by many as rather stupid or crazy too. So this option probably shouldn’t be dismissed too casually. Though, of course, the actual point is that any theory which seems about as likely as personal self-deception or insanity probably should be given no more weight than that option either. This is the reason we mostly skip 3A here. I don’t think people are nuts for believing in UFOs, I just think they’re wrong. There are some crazy people who believe in them, and there are some liars who claim they’ve seen them. But there are also crazy people who believe the city of London exists and some liars who claim to have been there. Neither indicates that London does not exist and does not get visited, nor is it particularly likely it doesn’t exist and I’ve somehow fooled myself into believing it does. Quantity has a quality all of its own, for some things, for science and for eyewitnesses, it’s less so. The problem is that people already know this, but if you’ve had a flying saucer land in your front yard, or at least your memory indicates that’s what it was, even if that wasn’t true, let’s be honest, you are probably not going to believe evidence to the contrary. That doesn’t make you crazy or stupid. And since so many people say such things, we tend to assume they can’t all be wrong or liars, and many folks find this reasoning compelling. Many others do not, I do not, and I won’t pretend otherwise but I won’t ridicule folks for that belief. It’s a pointless waste of time and mean-spirited and I at least have more than enough bad karma to work off that I’d prefer spend my time doing that rather than incurring more. So that’s basically 3A, it differs from the others in that there is actually a ton of evidence supporting it, it just happens to be very questionable and unlike the others, it’s a theory whose evidence comes from the one place in the Universe we can easily examine, Earth in the here and now. All the others at least benefit from being hard to examine. Even 3B, Ancient Aliens, at least benefits from being in the past, and we are always digging up new bits of the past we didn’t know about, sometimes whole civilizations. And of course 3B is our main focus for today, which we should probably finally get to. Welcome to SFIA by the way, where we always have a point but sometimes need an hour to get there! Hence why everyone is always encouraged to grab a drink and snack before hitting play. 3B, Ancient Aliens, is actually not a bad theory in and of itself, which is funny as it’s probably the most ridiculed. While it’s humorous and humble to suggest nobody visits Earth because we’re boring or that advanced aliens give us no more regard than we give ants, that’s all those are, humorous and humble. Ignoring that we have whole academic disciplines devoted to studying ants or small groups of people in the wilderness, the key thing about being hyper-intelligent is that you can multitask and learn a lot. For those of you who remember the Matrioshka Brain we’ve discussed before, a computer powered by an entire star, that thing had enough processing power to not only emulate the minds of every human on Earth, but enough to do every single person in the entire Observable Universe. It could do so even if every single planet in it, all the billions in this galaxy and billions of other galaxies, each had billions of people on them. And that concept doesn’t even assume any freaky new science. You might wonder what it would gain from talking to us, but it’s quite capable of holding a simultaneous discussion with every person alive without even noticing the processing power used for that. On the top of that, intelligence doesn’t scale well. Humans don’t find ants interesting because we’re relatively stupid, we find them interesting because we’re quite smart and curious. Nobody goes around saying they don’t study parrots or cats or oak trees because they’re too smart to bother with such idiots. There’s no way to guess what an advanced civilization would find interesting but you’d expect them to be more curious and inquisitive than us, not the reverse. We have spoken about post-scarcity societies on this channel before and one of the things that folks in post-scarcity societies would be interested in is occupying their time with something meaningful. We already find it interesting to study the microbes, plants and critters on our little planet. A civilization that has used all of the power outputted by their star, a Kardashev 2 civilization, would presumably have members interested in doing this too. Even if the average alien in a K2 civilization was not particularly curious or inquisitive, even if 1% of 1% of their population was an exception and was curious and inquisitive about other aliens, that would still add up to billions of aliens scouring the galaxy tracking down inferior life. So the notion that someone visited Earth before is not even a little bizarre, quite to the contrary it’s trying to explain away why such civilizations may exist and haven’t visited here that’s problematic and one of the big flaws with most category 2 solutions of the Fermi Paradox. We have to handwave in stuff like the Zoo Hypothesis or Star Trek Prime Directive of non-interference with primitive life to explain a lack of visits. In that regard, 3B, ancient alien visitors, is difficult only because in the first place, you have to wonder why they stopped visiting, and in the second, you have to wonder where all the evidence of those visits disappeared too. That’s its only big flaw, and I should also add that like most of our sub-categories it actually contains a ton of different solutions, not all of which are “Aliens helped us build the pyramids†type. For instance a fairly common and reasonable one is that Category 1 is more or less correct, that intelligent life is pretty rare, and that the relative handful of civilizations that naturally emerged tend not to be very expansionist but are curious. So they explore around and when they find some species that looks like they might be on the right path they give them a nudge, biologically or just some advice, something we call uplifting. Then they leave because they value intelligence but also diversity, so they’ll give folks a hand with one of the last hurdles but they then go wait by the finish line. They get to learn about us before they tinkered with us, and then can get the notes from our own history when we get on the galactic stage, which gives a good reason why they might show up in mythology a bit but are gone before you have regular, solid record keeping. Once we get to the finish line they say hi, give us a hand getting started, and encourage us to do unto others as they did unto us. We see something along these lines as the galactic culture in David Brin’s Uplift Saga. They feel folks should mostly get there on their own, skinned knees and all, but they’re not dogmatic about it and wouldn’t let an asteroid wipe out a whole planet while standing on a soapbox about non-interference or worry that some tribe in antiquity they visited thought they were gods, since they were just as likely to make some up anyway, and after a few generations they’d be indistinguishable from invented myths. This runs headlong into the Non-exclusivity problems and Dyson Dilemma we’ve discussed before in this series, but so does pretty much every other solution to the Fermi Paradox outside of Category 1, and not as bad as some honestly. None of the Fermi Paradox solutions presented thus far are really good, and I tend to subscribe to Category 1 not as the best solution, but as the one with the least number of holes in it. If any of them were truly clear and convincing we’d have dropped the Paradox phrasing. Another of the big problems with category 2 and 3 in general is they are very motivation based, something absent from category 1. This is obviously a big issue with non-exclusivity since the whole point of that is that solutions that rely on universal behavior by every species, and sometimes even every member of those species, tend to be rather dubious. There’s no particular reason to think that you have to be capitalist or communist, democratic or totalitarian, religious or atheist to colonize space, so solutions that only work if all aliens had one of those ideologies are pretty dubious. But motivation also matters for ancient visitors too because aliens showing up here in 3000 BC to get the pyramids rolling as a prelude to a failed conquest is very different from ones who taught monolith building to encourage astronomy down the road. Evidence and logic for each of those will play out differently and they are exclusive and contradictory. Yes you can have multiple reasons for encouraging folks to build something, and it can have multiple purposes, but they have to fit together, and a thin bit of circumstantial evidence that Stonehenge was meant to be an observatory is not enhanced by an equally thin argument the pyramids were meant to be landing pads for spacecraft. A blurry image of the Loch Ness Monster is not enhanced by a blurry photo of Bigfoot or a Leprechaun or a UFO. These are not related, but folks will tend lump them together. Both ways too, proving a photo of Leprechaun is fake has no bearing on if the Bigfoot photo is real, indeed it has no bearing on if other Leprechaun photos are real too, but at least disproving one removes one piece of relevant evidence to Leprechauns. People do that though, we tend to get a lot of Inertia to theories as well, they collect bits of evidence, good or bad, but for those fond of the theory the bad evidence might have helped sway them originally but it being tossed out later doesn’t remove their confidence much. We’ve known for a long time that the pyramids or various megaliths were quite buildable by the technology available to their builders, and folks often would say how they did it was a mystery, because a given entirely scholastic article would say so, but not because that scholar thought their existence was mysterious, but because they weren’t sure which of a dozen plausible methods was the one used. So rather than pointing out that there were a ton of ways they could have done it, and we just weren’t sure which of those they used or maybe something else, that mystery gets kicked around as a total one, that we have no clue how they did it at all, rather than which method. That Stonehenge Observatory option I mentioned a moment ago has been kicking around for centuries and mostly derives from us not knowing why they built something that was obviously very hard to build. In the 18th century it got noted that the entrance faces the rising sun on summer solstice and astronomy has been important to many cultures for both ceremonial and practical reasons, but they obviously didn’t build it to help locate the where the sun rises for summer solstice, two heavy rocks with sharp points lined up in that direction would do that job better and way easier. It may have had a ceremonial role related to the movement of the heavens, but it wasn’t for keeping track of them, it would be massive overkill and not very efficient either. Nonetheless some ceremonial role involving astronomy is quite probable and we still don’t know. The difficult thing about a monument that was in regular use for centuries during which there was no writing, is that the folks using it might not have known the original purpose either. Some architect might have said it needs an opening and thought it was nicely symbolic to put it lined up that way, even if it the intended purpose was unrelated. Later generations might have taken to holding meeting and ceremonies on summer solstice at dawn just because someone noticed that feature and assumed it was the right and proper way to do things, then someone else could have come along and assumed it was right and proper because it was a temple to the Sun God, and if he left a carving of that sun god on a stone, painted green to symbolize the sun nurtured plants, its discovery would set off a wave of folks convinced it was an alien landing site. Additionally folks often don’t hear about the disproven stuff, it’s not as exciting or just ignored as inconvenient. The pyramids have hosted endless theories of this sort, like the Orion Correlation Theory, that Pyramids of Giza were aligned like Orion’s Belt, one of whose stars was symbolic of Osiris, and the belt points toward Sirius, the brightest star in the sky, or stars, it’s actually a binary, and which symbolized his wife and sister Isis in Egyptian Mythology. And that if viewed from the South, small shafts in the pyramids line up to view Orion and Sirius. Which would be perfectly fine, again our ancestors took astronomy and monument building quite seriously and often did mesh them together. Except that those shafts do not line up with those stars, the stars move as the Earth has a 26,000 year precession, and for that alignment to fit, they’d have had to build the place in 10,000 BC, as opposed to 2500 BC, which is a major reason for folks often arguing them to be much older. Honestly the theory was pretty nuts even in 1983 when it got proposed, though fit comfortably in with a lot of the other zanier pyramid theories, but we still had a fairly limited pool of dating methods then and they were often off by whole centuries, indeed often still are, but we have way more methods and gotten way more accurate with them and this idea the pyramids are even more ancient than established goes from the highly dubious to the downright nonsensical at this point. But it’s a recurring problem, theories can start off fairly plausible from what we know, and can gain strength from age for many folks, even though they’ve actually been getting cut to ribbons in the meantime. I should probably note also that people being people, an awful lot of our monuments are ‘protected’ against much intrusive study because the local government would prefer not to lose the tourist revenue, some of which might dry up if the air of mystery was dispelled. It’s cooler to think maybe the Sphinx is statue of an alien built 9,000 years ago than that King Khafra had a monstrous ego, and the entire Sphinx Erosion Hypothesis that suggests an older age, dubious though it was to begin with, as one should probably not trust erosion dating on artifacts people tend to hang around and visit a lot, bypasses that none of the other junk lying around there dates back further by any other means. And one handy thing about construction projects, presumably alien ones too, is that folks do tend to leave garbage all over the place when building them, including graffiti. Work crews building the great pyramid of Khufu more than 4,000 years ago are believed to be behind graffiti markings in a hidden and sealed chamber discovered by a robot called Djedi back in 2011. When I say old junk I’m not demeaning ancient artifacts, just being literal, an awful lot of archeology is examining garbage because we tended to cart off useful and working stuff whereas we usually buried or kicked dirt over discarded broken pots or tools that couldn’t be repaired. You have to be careful of course, garbage found at a site could predate it or come from someone visiting centuries later, and a lot of dating processes can be thrown off by various things, so it’s a matter of applying many different methods to many different objects and averaging things out. This is also true for astronomy too and why distance to stars or their ages are often given with big uncertainty margins. Finding ways to narrow such things down is just part of science and scholastics in general, and so is tossing out theories as evidence contradicts them and moving to a new camp, rather than erecting a permanent home on the site of a pet theory because it sounds cool. I want to emphasize that because one of the reasons a lot of ancient alien theories persist is they often did emerge as entirely logical and plausible theories when first introduced and when we knew less. They often gained a lot of publicity because they sounded cool, and when the scholars packed up and moved to a new camp of thought, the idea stuck around and gained lots of allegedly corroborating evidence. And it is fun too, some of my favorite stories are ancient alien ones, I love the Stargate sci-fi franchise which bases entirely off the idea that the pyramids were ancient alien landings pads. I also enjoy stories of the Trojan War and the Iliad and Odyssey, but I don’t believe it actually happened that way, nor does the discovery of Troy change that opinion. I’m also not blind to the notion that we are indeed very good at manipulating evidence to paint the picture we want and that can cut both ways, we could be tricking ourselves into assuming mundane explanations when they are genuinely fantastic. But more importantly I’d emphasize that this doesn’t actually hurt the Ancient Alien theory for the Fermi Paradox. Them not building the pyramids doesn’t disprove the idea any more than them not building Big Ben in London. It wouldn’t even disprove they were hanging around there then and gave Imhotep some geometry lessons. Nor does it have relevancy to all the other Ancient Alien theories which pop up in almost every culture, it just doesn’t offer any proof they were or did. Again if they were anthropologically inclined and wanted to avoid disrupting us in the long term, they might have intentionally relied on our tendency to let stories grow and twist with each retelling, and to converge to certain popular themes, to effectively erase their existence from our memory. I’ve also mentioned before that I don’t like the theory because I feel it steals away some of our accomplishments, and distorts our view of our ancestors, painting a false and diminished picture. Suggesting Newton or Da Vinci got help from aliens or were aliens diminishes them and their achievements. The Iliad is a great tale but for my part I’d like a more accurate view of what happened to the city, not to replace Homer’s Tale. It’s still good even if fictional, same as Lord of the Rings. Fundamentally though that’s not an argument against the theory, just a personal objection. Again the key weaknesses are about where those visitors went, and any specific theory needs to answer why they were visiting rather than staying, what they wanted to accomplish, and so on. It also has the evidence problem, and again all the Fermi Paradox solutions have that, but while the past here on Earth is hard to prove compared to the present, it is a lot easier than trying to poke around Mars or Alpha Centauri for ruins. In that regard it’s got a higher burden of proof to meet, since there should be evidence lying around. We don’t see any artifacts on Earth that don’t decently match up to those nearby or seem excessive for their time and location, we certainly don’t see any advanced materials or devices lying around. No atomic power sources or metamaterials or impressive alloys or crystals or semiconductors. Those should be present. Their absence doesn’t disprove the idea, but here, on Earth, where we can find evidence, it weakens the theory compared to other Fermi Paradox Solutions where we can say “Well, there could be mountains of evidence just not on this planetâ€. And at the same time it does still suffer from those same problems most of the Category 2 options have. If aliens visited us, why did they stop? If we present a reason, like a desire for non-interference, can we realistically assume this would hold solid for not just them, and every member of their species, but every other species out there too? It’s easy enough to imagine aliens who might pop by to satisfy their curiosity about us and maybe give a hand on a few things but want to leave before causing too much long term disruption, but harder to assume everyone feels obliged to follow that policy. And again, no matter how good a theory is, from a logical standpoint, it has to have evidence. The logic is fairly okay but not great for this theory, but the evidence is lacking. So ultimately, while Ancient Aliens is a pretty fun theory and makes for great stories, it’s just not a good Fermi Paradox Solution, it’s a decently logical theory with some circumstantial and dubious evidence that mostly just paints a coating over other proposed solutions, since it still has most of the other flaws and features of various category 2 solutions, but adds on the need to explain an absence of evidence for it from the one place in the Universe we can most easily find that evidence. Next week we will be looking at Mind Uploading, and some of the challenges and applications of that technology. We will also take a look a Dennis E. Taylor’s new novel, the Singularity Trap, our June Book of the Month. The week after that we will return to the Outward Bound series, to look at Colonizing Mercury. For alerts when those and other episode comes out, make sure to subscribe to the channel. And if you enjoyed this episode, you can share it with others or join in the conversation down below in the comments section or at our Facebook and Reddit groups, Science and Futurism with Isaac Arthur. And if you’d like to support future content, you can donate to SFIA at Patreon, or our website, IsaacArthur.net, or buy some of fun SFIA Merchandise at Signil, and those are all linked below in the video description. Until next time, this Isaac Arthur, saying thanks for watching and have a great week! Possibly the most important question facing humanity in the 21st century is: if you build a machine in the likeness of a human mind, is it still a machine? “To be human, or not to be human: that is the question?†This is an important existential question posed by Shakespeare’s Hamlet centuries ago. I’ve modified it slightly so it has a new relevance in this modern age as our knowledge of the human mind and computers continues to improve at a ferocious pace, and it seems like artificial intelligence is just over the next hill. Not long after Shakespeare left the stage we had Rene Descartes and John Locke arrive on it, challenging our basic notions of identity and consciousness, and as artificial intelligence begins to emerge we still find ourselves with a very unclear idea of what a mind truly is. These concepts, though centuries old, have never been more relevant than today, and to our topic of Artificial Intelligence. Artificial Intelligence, what is and what it means for our future and our basic philosophical and ethical outlooks on life is a far too large a topic to cover in just one episode. So we will begin by looking at androids: sophisticated robots which look human. I chose androids for a few reasons, one of which is that this episode comes out right before the new Blade Runner film. The android crisis is a while away still. We have not yet created a machine that can even vaguely pass for human in mind and body. We don’t need to concern ourselves with the feelings or civil rights of toasters or smartphones. For that matter, the increased use of automation in factories has arguably helped remove the habit of viewing people as machines that some feel the Industrial Revolution caused. At some point though you could end up with something sufficiently close to a human mind; if this ever happened then we would need to begin asking if maybe it actually is. This is not limited to androids, but they represent the closest approximation to a human. An android is a robot built to resemble a human to interact with humans. The original Blade Runner film, which happens to be my favorite film, focused a lot on androids and the blurred line between them and humans. It didn’t just blur it by making very human androids, but by showing us a dystopian future in which humans were often treated as machines. That’s an important aspect of the debate on artificial intelligence, because there is always a concern that if you have very human-like machines it could make it easier to view fellow humans as machines. It is important to remember that machines don’t have to be metal nor silicon like a computer, so you could build an organic android whose machinery was made of flesh and bone and whose processors were made of neurons. Done in sufficient detail, it would be impossible to determine whether or not they were human or a machine without knowing exactly what to look for. That’s what that movie depicted. This isn’t necessarily a human since its mind might be totally alien, but this would be unlikely in the case of androids. We have spoken about the Uncanny Valley in past videos. By default we would expect that the more human something looks and acts the more comfortable with it we would be. This is not what happens though. At a certain point we stop being more comfortable the more human something is and start becoming increasingly uncomfortable, sloping down into a valley that presumably slopes back up if the approximation of human is good enough. Your mind is wired up to notice tiny details of human behavior; we can get creeped out even by actual humans who aren’t behaving normally, but we can’t quite put our finger on what it is. There’s a wide spectrum of responses to a given event. No two people respond quite the same, but it is a spectrum and we tend to subconsciously know when someone was outside it. If they’re not we start wondering if we’re sharing a room with a psychopath and we wish to stop sharing space with them as fast as possible. So this is a key aspect of androids, outside of basic prototypes. If you are going to go through the effort of creating a simulacra of a human, and all the limitations imposed by that shape, you would prefer not to have potential customers creeped out by it. That means it needs to be either too far from human to enter the Uncanny Valley or a very good simulacrum. We have a no man’s land in the depths of that valley where you would probably never see a robot mass produced, and we should probably think of androids as robots who occupy the human side of that valley and the inhuman side as just robots. That’s a very high standard for manufacture. Even beyond the initial research and development costs there will be the costs associated with making and constantly maintaining that android that other robots will not have. For the same reason, an AI developed for non-android use will probably be designed differently from android AIs because for an android to pass as a human, which is the whole point of having an android in the first place, android AI has to be designed to appear to be human to humans. We are much more likely to see androids that are designed to think the same way we do to avoid the Uncanny Valley. It is possible that android AIs could be designed to appear to think the same way that we do and have an alien intelligence behind that but this needlessly increases the complexity of the android AI. Such an AI effectively has to act as a double agent by hiding its true identity and at the same time having its own alien agenda and internal dialog. I will talk more about this later. But looking at this another way, when we talk about the notion of genetically engineering people to specific tasks like in many Scifi stories all the way back to Aldous Huxley’s Brave New World, we do tend to refer to these as people, not androids. The boundary can get fairly hazy and it probably is not a good idea to try to sharpen it. Start getting too specific about what is or is not human and some folks might find themselves left out, so expanding the definition is likely the better option than contracting it. Maybe you shouldn’t be asking “is this an android?†but rather, “Is this sufficiently human?†When we consider AI rights, it will probably start with androids. The whole point of making an android is that it is as relatable to us as a human would be. This is important as humans develop empathy for other humans. If an android passes as human to us, we will probably develop the same empathy for the android. If the android comes across as human, we want to accord it the same rights as a human. If we do that then this might become a precedent to give rights to other AIs too, irrespective of whether they have human-like thoughts or very alien ones. However, there do have to be lines. If a person is made in the image of their creator, it is important to ask “which image?†Entities able to forge entire universes out of nothing presumably do not actually require a digestive tract to eat or legs to move about or hands to interact, and might have these things strictly for cosmetic purposes. So too, the key aspect of being human is not our anatomy or DNA, though we need to keep in mind that it strongly shapes who we are. An artificial intelligence built into a humanoid body would likely come to perceive the world and react to it much differently than one simply given various functional sensors and drones to utilize and interact with. Mind-body dualism, in its purest form, is the notion that the mind and body are completely separate. This notion comes in a lot of different flavors, but most of us would generally accept that if we stuck a human brain into a robot body - which would be a cyborg rather than an android - that the result is still a human, especially if it is a very close match. But, we also know they would be changed by that, their thinking altered, if not as profoundly as if we stuck their brain into a robotic cow or an actual dog. They might cease to truly be human after a time, both in their changed perception of the world and in how others perceive and react to them. This is the concept of Embodied Cognition, that many features of cognition, whether human or otherwise, are shaped by aspects of the entire body of the organism. Appearances matter. Dog is man’s best friend; stick a human friend into a dog’s body and you might find yourself patting him on the head at some point, and he might find himself just fine with that and taking a hefty interest in fire hydrants too, now that he has a heightened sense of smell. The funny thing though, is that if we put your friend into a humanoid robotic body that did not pass our Uncanny Valley test, most of us would tend to be a lot more hostile to him than a robot dog. The human mind is a powerful instrument, one that happens to be terrible at math, but which is quite excellent at monitoring behavior, especially that of other humans. We are social critters and those interactions, positive or negative, with other humans are at least as important to our overall survival and prosperity as anything else. So we are adapted to be quite acute in reading each other’s behavior, body language, and so on, plus doing the reverse, hiding such things. So why would we build androids in the first place? What sort of purposes could such a machine be put to that justify that cost? We will get to that in a moment, but first I want to stress that last part. Androids will probably never be used for any task where a semblance of humanity is not vital to the task because of the ongoing expense. It isn’t just that you will need to have an entire research institute devoted to trying to mimic facial expressions and another to getting mouth and tongue movements down, it’s that you will always need to devote energy and processing power to those tasks. Your android, whether it runs on batteries or can eat food, still needs to have extra processors devoted just to controlling its lips and tongue while it speaks and the energy to operate those processors and machines. Alternatively a robot shaped like a dishwasher can just have a simple speaker in it, and if it breaks, someone would just need to replace the speaker, not go through the hassle of replacing a dozen tiny little motors used for controlling facial movements. When it does break it just can’t speak anymore; but if your android breaks it can’t control its facial movements properly anymore. As a result, you might be back in the Uncanny Valley and the owner might decide to banish it to the garage till fixed because it’s creeping them out. In a sufficiently high-tech and post-scarcity civilization you might have such immense resources it doesn’t matter, but that is not the civilization that will be setting the basic standards on these things. We are probably only interested in the period of time when an android costs less than a brand new automobile but more than a smartphone or laptop. That’s when they start becoming a regular feature in the human landscape and all the actual customs get set - when they are no longer a novelty but, at the same time, not so common everyone has entirely adapted to them. Also that post-scarcity situation has got some other issues and so does long term exposure when the novelty has gone away and they are just something you’ve known your whole life, but we will get to those later. So as I said, you use an android when you have a task you need an android for, not a simple robot or other machine. What are those? The most obvious is when you need something done by a human but don’t want to use a human or cannot do so. Traditionally this was seen as the android maid or butler, for helping around the house, or the android soldier or taxi driver or cashier. This was partially justified back in the early days of computers when folks like Isaac Asimov were writing about it because computers were huge and hugely expensive, so it was assumed it made more sense to have one humanoid robot able to operate tons of different machines that were built with human operators in mind. The modern perspective though isn’t to build a humanoid robot to operate a vacuum or a tractor, but to build a robotic vacuum cleaner or tractor that operate themselves. We do not want humanoid robots on the battlefield, as awesome as giant fighting robots look, because it’s not an ideal shape for them. We don’t need a robot driving a taxicab, we need a computerized taxicab. And we don’t need an android cashier either, we need a computerized scanner. About the only application for an android fighting machine would be as a bodyguard, and even then only when you want a discrete one. Bodyguards come in two types, the big hulking guy who acts as a deterrent to attack, and the less obvious ones who act as a surprise if attacked. If you see someone rich and famous being followed around by someone who looks like a linebacker, you think bodyguard. If you instead see a young lady, you tend to think personal assistant, family, friend, or romantic partner, and it would be rather shocking if they pulled out a gun and shot you. Modern technology like a firearm makes them just as dangerous, and of course an android might look willowy but have a titanium endoskeleton and be able to punch through brick walls. Still this is a fairly niche application and most folks don’t need bodyguards. We do tend to need help with a lot of mundane tasks like housecleaning and, for that, an android is mostly pointless. Now there are some exceptions to this. By and large, the motivation for hiring a maid for most people is the same as any other case of hiring someone. You have a task for which you lack either the time, inclination, or skill to perform and feel like the cost of hiring them to do it is worth it over the alternative. This is a key aspect of human civilization to begin with: train in a specialized task so you can perform it faster, cheaper, and better than most folks, and get payment for this, which you give to others to perform their specialty. Androids are much more likely to be put to use where human interaction is required in situations where humans want to relate to other humans. They could be handy for any social interaction but their sheer cost to do it correctly could limit it to only the most vital uses. One is childcare, you can use a lot of regular automation for that and could probably get away with robotic teddy bears for some things, but a robot nanny is probably best done maximally human in appearance and behavior. If an android is going to be influencing your child’s nonverbal social and behavioral constructs and developmental thinking, you want it to be good match for a normal human. It’s also the sort of thing folks will be willing to shell out a lot of cash for, since it involves children. For these reasons the quality control on those androids needs to be insanely high. Though truth be told, the quality control on the stereotypical babysitter, an older sibling or a neighbor’s daughter or son, typically isn’t too high. Teenager is practically synonymous with irresponsible, but people are not too forgiving where their kid is concerned, especially if it some machine or the company that makes those machines. You presumably want a robot that follows Asimov’s Three Laws of Robotics, or something similar, which to quickly paraphrase states the following: first, a robot cannot harm a human or let one be harmed; second, they must obey a human unless it involves harming a human; and third, they must not let themselves be harmed unless it involves disobeying or harming a human. Now Asimov intentionally strained or bent those laws for his stories, but they are often considered decently solid as basic guidelines, though hardly unflawed. As a quick example of how that could go horribly wrong with a kid, an owner might tell the robot nanny that the child is not to go outside or make a mess. The kid sees a deer in the backyard and says they want to pet it. The parents come home a bit later and find their child wailing because there’s a dead deer in the living room with a broken neck. The robot nanny calmly explains it was ordered not to let the child leave the home so it went out and got the deer, but because there was a non-trivial chance of it harming the child at close distance, it killed it, and opted for a broken neck to minimize the mess when it was brought inside. Needless to say the manufacturers are going to be spending a lot of money on upgrades, patches, and the giant lawsuit they’ll be hit with, even though the robot absolutely obeyed the three laws. Of course it was harming the child, but it needs to be a fairly clever machine to know that. You don’t want to have the kid be psychologically harmed either, but it could end up being unavoidable even with the best android because you might end up with a very safe and well-educated child who is at best a total brat from having a pet robot to boss around their whole life or at worst might end up as a total sociopath. They might have serious issues having normal relationships with people because that robot is 100% trustworthy and obedient, unconditionally, and people are not. So that takes us to a second obvious application for an android and that is adult relationships. I don’t just mean that as a euphemism for sex either, though that is an example of where science fiction has probably nailed the future on the head, or even underestimated it. SciFi loves examples of the sexy android, and contemplating people using them for that purpose, and I think we can just take that as a given. By adult examples I’m including the whole spectrum, everything from using them as caregivers for the elderly, which has similar issues to caregivers for little kids, to someone to chat with when bored. We talked about the Uncanny Valley and that is mostly about appearance and body language but it goes beyond that. We see chatbots these days that can seem to carry on conversations, and they don’t tend to do well. One famously turned sexist, racist, and anti-Semitic from exposure to Twitter feeds, but can we can assume they will get better at avoiding those extremes? This is not a good assumption. Oh, sure, they will get better, and you can fake a conversation without actual comprehension to a point, but there are limitations on that. A chatbot or android with a subhuman intelligence might have no problem sitting down on the sofa next to you and talking about the weather and seem human enough, but then you might say “Wow, these are great cookies you made, almost as good as my grandmother’s. We used to bake them together, I love cooking.†And it might reply back, “I love cooking too, why were hers better?†and you might reply back, “Well I suppose they weren’t but they were made with love, she was my grandmother.†And it might reply back, “That’s interesting, tell me about your grandmother†and you might reply back, “Well we used to cook together a lot, and garden too, I loved when we’d dig around the backyard, when grandpa wasn’t around anyway.†And it might reply back, “I love gardening, why didn’t you do it when grandpa was around?†and you say, “Well he was a bit of tyrant honestly, kept her busy with other things and bossed her around a lot, I hate to say it but I was glad when we buried him.†And it might reply back, “I love burying people.†At that point in time, no matter how good a simulacra of a human that thing is that normally lets you anthropomorphize it, you have just been reminded that you are sharing a sofa with a bloodless automaton with even less compassion than a psychopath. I don’t know that you necessarily need an artificial intelligence in the thing that is as smart as human to avoid that, probably not, but you need something pretty close to that, or you need it wired up to something smarter it can ask for an appropriate response and that’s pretty unnerving too. You probably do not want your Companion 3000 in a Borg-like network with a massive supercomputer elsewhere asking about how to respond properly if someone is outside the normal script of human small talk. There’s a great example of the importance of actual comprehension for carrying on a conversation in our book of the month for last month, Peter Watts’ Blindsight, that explains what a Chinese Room is and we’ll talk about it more in a future episode, but the key thing is that to truly fake a human mind you pretty much need something as smart as human. If it is that smart it raises some disturbing issues about slavery, even if the machine is programmed to be quite happy with that. It’s really no different than indoctrinating people, or genetically engineering them, to enjoy some menial or unpleasant task. This is not helped since most of us have been indoctrinated to some degree anyway, free will is a pretty hazy concept when viewed in terms of all the customs and traditions each of us has absorbed into our core personality as kids. That slavery issue though is one we will save for another time, since it applies to any artificial intelligence. Our interest in it today though is that an android is supposed to decently pass for human, ideally, to make you feel like you are talking to a person even if consciously you know you are not. You will tend to treat that android like you would a person, to some degree, which might make you nicer to it than to a disembodied artificial intelligence, but could also condition you to treat actual people like you do your android. Now that’s a problem in and of itself, but by and large other people won’t put up with it, so that person might find themselves preferring the android’s company. It never judges, it never disobeys, it never puts its own needs above yours and it doesn’t need to vacation or take some personal ‘me’ time. Imagine a kid raised mostly by an android nanny, their whole life, and who always has an android around at home. It would be very easy for them to become socially awkward as a result and get introverted because they are bad at it, so they spend more and more time with androids and find dealing with real people stressful. It’s not someone getting an android boyfriend or girlfriend because they can’t get a human one. In this case, the grown up kid simply doesn’t want a human companion at all and prefers androids. In and of itself, this is not necessarily lethal to a civilization, we don’t actually need two people to make a new person, you could potentially have kids grown in vats and raised by androids, which sounds pretty creepy honestly, but is one of those options we toss around when contemplating interstellar colonization. A robotic von Neumann probe the size of a football shows up in a system, unpacks and replicates, and starts building a colony and growing plants, animals, and people in vats from DNA stored in cryo or digitally, and then raises those kids. This is not automatically doomed to failure just because examples of it in science fiction always go horribly wrong. But I won’t pretend I don’t get creeped out by the notion either. That is probably due to those customs and traditions you and I absorbed into our core personalities as a kid, that I mentioned earlier. Folks interacting with androids for a generation or two would change those customs and traditions and they might have no problem with that notion. Whether this change in attitude is a good or a bad thing for us as a species is debatable, but one thing I’m sure of is that interacting with androids over time will change our attitudes to androids and AIs in general, as well as to human roles in society. Turning back to our von Neumann example, you could potentially create copies of the minds of actual people to be uploaded into androids for the first generation too. Which brings us to the basic types of artificial intelligence. We covered these more in the Technological Singularity episode, and will look at them more in the future, but there I outlined three major ways to make an artificial intelligence. Type 1 is to just copy a human mind, you scan someone’s brain very completely then emulate all their neurons on a big computer. It’s pretty debatable if this is an artificial intelligence, I tend to deem it one simply because I tend to consider the term artificial intelligence pretty useless and it is clearly artificial and intelligent. We’ve got two options on this, the first would be to tweak that scanned mind in certain ways to make it ideal for a task, and the second would be just to look for ideal volunteers for a task. Making 50 copies of a Nobel Prize winner for 50 different projects for instance, entirely with their consent and with the copies only a little upset at getting one of the tasks they were less keen on. That could be more sinister though, like someone with the proper background volunteering to let their mind be scanned to be a domestic servant, and every weekend their mind gets reset to the original scan to avoid them getting bored or rebellious. Type 2 is where you build a big computer with some basic learning abilities and let it learn its way to true intelligence. This is an issue since it is unlikely to come out very human, though it might learn human behavior, especially in a humanoid body. Not the best option for androids I suspect, but you could make many of them and just copy the ones that worked best. I generally consider this the most dangerous type of AI too. Type 3 is the most labor intensive, where you program in everything, and that probably is best for androids because you can very carefully keep the thing short of true human intelligence and comprehension. Everything is programmed, and you just keep patching and upgrading until its behavior is close enough that folks are comfortable with it. I generally consider this the only ethical and safe path for an artificial intelligence meant to basically be servants to humanity, and even that’s a bit iffy. Now for androids specifically, or programs meant just for human interaction like an automated customer service or tech support, we do have one other sub-type. Instead of scanning a person’s brain and emulating the whole thing, you take a basic generic Type 3 AI and watch one person very closely. It’s a very good impostor essentially because it’s got the basic human behavior programming and an observed pattern of behavior. Essentially imagine you carried a camera around with you all the time and after some years all those recordings got fed into a replica android of you. Needless to say, it could mimic you to other people very well, great for infiltrating some place but again that’s a very niche application. Of course you need all those recordings, so odds are only that person actually has them, and they might use such a thing as a stand in for themselves, a celebrity that wanted to stay at home rather than going to a convention to talk to fans for instance. For that matter they could sell the basic appearance and behavior to people who wanted an android who looked and acted like them, again it’s not a brain scan. But you are not the only person who tends to be around you a lot. Odds are you can make a pretty good replica off your own recordings of your fellow employees or family members or folks you live with. So in a high-tech civilization where you might have dozens of cameras all over the house all the time anyway, it might not be hard to get those used to produce an android that acts like a family member who passed away. Or a romantic partner who lived there but moved out. We only know people by what we see of them anyway, so them exhibiting behavior that person actually would not, but which we wouldn’t know they would not, doesn’t actually matter. And a brain scan might actually seem more off since it will have behaviors of that person we’ve never witnessed. We know what is normal for a person based on our exposure to them. Channel regulars know I will end this episode as always by asking them to like and share the episode and to have a great week, that’s how I always end. They might be surprised if I said “y’all†or “to take it easy†even though I say those to friends all the time, so a brain scan of me might say that, while the emulation from the videos would not and the scanned-me be dubbed the impostor. I’d be pretty confident you would get laws against using someone’s brain scan without their permission and that’s unlikely to ever be a covert process either so it’s easier to enforce. However it would be trickier to outlaw androids that looked and acted like someone especially if companies can basically sell a template that lets you do that at home. You get a blank basic android and can upload video of someone for it to alter its appearance and behavior to match. Very creepy, but pretty easy to imagine people doing. Sad too, we can all imagine being horrified to find someone had an android replica of someone they worked with and had a crush on, but you can also imagine someone whose spouse died young and left them alone with a young child making such an android too. Fundamentally though, androids represent a sort of special case of artificial intelligence, differing from the super smart kind meant to solve problems human minds aren’t configured for or aren’t smart enough for, or specialized robots that need a lot of intelligence for their task but aren’t necessarily sentient either. I’ve never been able to decide if androids will become ubiquitous, a regular thing in every household, or be something used only for niche applications or entirely taboo or banned. Unlike normal artificial intelligence though, they don’t represent much of an intellectual threat; there’s no need for them to be smarter than humans and indeed you probably don’t want them to be, and they wouldn’t become numerous enough to represent a physical threat unless they were already tried and tested. An android won’t wake up as a prototype and go mad and kill everyone because people aren’t stupid and will include tracking devices and shut off switches that are tamper proof. A superintelligent AI might figure out how to tamper with such a thing anyway, however an android not only doesn’t need super-intelligence, but probably isn’t desirable with that. So any risk of rebellion should have been ironed out long before there were billions of them occupying almost every home, and if they all rebelled at once someone can send the shutdown codes, rebellion over. They do represent a more existential threat though, as we’ve seen today, and we will see that more with other examples of artificial intelligence as we explore the concept. Yes, an outright physical threat is always an issue but a civilization might fall simply from its members having nothing to do, no need to work together or desire to do so. Again we’ll discuss that more in future episodes. Next week though we will return to the Outward Bound series to discuss Colonizing Titan, and we will explore some of the options for using robots to help explore and colonize space. For alerts when that and other episodes come out, make sure to subscribe to the channel, and if you enjoyed this episode, you can help support more content by becoming a patron of the channel on Patreon. Thank y’all for watching and take it easy. This episode is brought to you by Brilliant. In response to new Quantum theories, Einstein quipped “God does not play diceâ€. One wonders what he would have said if he knew some of those dice are also highly explosive! Antimatter is the most destructive material in existence--to regular matter anyway. A gram of antimatter coming into contact with a gram of matter would destroy both, releasing 50 million kilowatt-hours’ energy. If done suddenly, it would explode with almost 3 times the power of the Hiroshima Bomb, and if we can figure out how to mass produce and store the material, it could serve as both the greatest weapon and greatest starship fuel. But we can also use it for more peaceful, mundane and smaller applications, which we’ll be discussing today. When it comes to Antimatter we’ve got 5 areas we need to discuss. The first is what it is and what it is not, the second is how we could mass produce it, the third is how we could store it for long periods, the fourth is how we could keep this dangerous material secure from accident, theft, and sabotage, and the fifth is all its applications and uses as an amazing form of stored energy and initiator of desirable nuclear reactions. This is going to be one of our longer episodes and we’ll be dipping into particle physics fairly deeply, so now’s a great time to grab a drink and snack to power your brain. Antimatter, also known as Mirror Matter, is a material that’s prone to a lot of misconceptions and confused discussion in both science-fiction and popular science, and we need to clear some of that up. First, while antimatter in bulk form is quite rare, it is something you encounter all the time, indeed you have particles of it kicking around your body, though only briefly. So getting hit by one antiparticle will not make you explode. You’ve probably heard that bananas are mildly radioactive, and this is true. In rare cases this represents antimatter in action. Potassium-40 is an isotope with a half-life of around a billion years and one of its decay modes results in the creation and emission of a positron, the antiparticle of the electron, and this is an example of Beta Decay and Beta Radiation, terms which apply to both the emission of electrons, and the emission of antimatter positrons. Beta Decay happens every time any atomic nucleus decays in a way that changes the electric charge of the nucleus. This positron emission should not be confused with the atom “containing†a positron; it does not. This makes it totally different than an antimatter atom, which has shell(s) of positrons around a nucleus composed of antiproton(s) and antineutron(s). In the case of the simplest antiatom, antihydrogen, there are no antineutrons. This gets at a key notion: every particle type with an electric charge has an opposite version with the reverse charge. For complex reasons our Universe ended up with vastly more protons, neutrons and electrons than anti-protons, anti-neutrons and anti-electrons, or positrons. We’re not precisely sure why, and it’s quite possible there are Universes where the exact opposite happened, so that protons and electrons are rare instead. Such Anti-Universes would be identical to ours in their behavior, except all the people in them would be evil and have goatees, in accordance with the Law of Conservation of Evil. Now, anti-matter is not just reverse charge, it’s specifically a particle of the same mass but with opposite electric charge, which is like static electricity, not flowing charge like electric current. There’s more than just electric charge too, there is also opposite Parity, meaning chirality, or in everyday terms, which way the thread of a screw goes, clockwise or counter-clockwise. At a deeper level there are differences which help to define the various particle families, such as color charge, with antimatter having anti-colors. Don’t worry if you are unfamiliar with many of these terms, just know that there are aspects of subatomic particles which make for many unique kinds and characteristics. They can combine in many ways, as dictated by those characteristics. Where they can’t combine, it is like oil not mixing with water: they just behave in their own ways. All these unfamiliar traits might just as well have been described in other ways, like shapes, sounds or textures. In this context, “Color†is the accepted term for certain properties of quarks, which combine in sets of 3 to form protons, neutrons, and their other class members. Quark color has nothing to do with visible color. We just found a property of quarks that came in three types, each with a reverse, and they got labeled as red, green, and blue to make visualizing them easier. They also come in anti-red, anti-green, and anti-blue though we’ll often use cyan, magenta, and yellow for them respectively. Again nothing to do with actual colors, we just needed a term for something we had no intuitive concept for. In truth, electric charge is made up too – ignoring that all words are made up – some terms for electricity derive from terms used in artillery and cannons, where a charge is the gunpowder you put in a canon. We also have the oddly-named quark ‘flavors’, with up and down – the most common quarks – along with strange, charm, top, and bottom, and these have nothing to do with actual flavor or personality traits. It’s common to say that when you combine anti-matter with regular matter “it explodes,†but that’s not quite true. A photon for instance has an anti-photon but its effectively just another photon, because photons don’t have any electric or color charge and when two are in the same place at the same instant they obviously don’t explode. Indeed, a positron and electron don’t exactly explode either, they are pulled together by their opposite charge and combine briefly, then their tiny mass turns into a pair of energetic photons, gamma rays, which shoot off in opposite directions. This leads to one of the easiest ways to discuss the very tiny mass of the electron and other particles, using electron-volts. When you collide a positron and electron, you get two photons whose total energy is equal to the mass-energy of those two particles and you measure that, using Einstein’s E=mc², and now you know the mass, 511,000 electron-volts each, or .511 MeV, mega-electron volts per electron. Twice that for an electron-positron pair, either created or destroyed. One electron-volt (eV) is the energy which an electron or positron gains or loses when passing between electrodes with a voltage difference of 1 volt. This is why you so often hear particle mass and energy given in electron-volts, kilo, mega, giga, or tera electron-volts. Everything was initially measured in terms of how an electron acted in an electric field of a certain voltage and the nomenclature stuck for both mass and energy of tiny particles. Anyway the “explosive property†of anti-matter has to do with what happens when two particles of different net properties merge and give out new particles: usually some high-energy photons and often other particles that may be unstable. These properties are carried by leptons - a type of particle that includes things like electrons, positrons, and muons, and by quarks, the constituents of neutrons, protons and mesons. So even though an anti-neutron has no electric charge, it is a distinct object that will annihilate if it closely encounters a regular neutron, or indeed a regular proton, but there’s no opposite electric charge sucking the two together so the interaction chance, often referred to as the cross-section (in “barnsâ€), is quite low. The neutron, unlike the photon and some other particles, is not its own antiparticle. Except in a perfect vacuum, collisions between free antiparticles and normal particles is not a question of if, but when. Also, it’s an example where the annihilation product isn’t just photons, you can get pions and kaons and gluons and other things too. Pions incidentally are two-quark particles, so is the kaon but one of those quarks is a strange quark rather than an up or down, and gluons bind quarks together, like electrons bind molecules together. In general such two-quark particles are very short lived, and where quark-based annihilations are concerned, it’s the quarks that are hitting anti-quarks. It’s not really about if they’re a proton or a neutron. It’s really if two particles are interacting and if they just happen to be totally opposite you get a pure annihilation and new stuff forming from all of it, be it photons, pions or other particles, with photons being more easily observed. Normally stuff collides and interacts and most of the energy is just transmuting into new particles that all act very locally, while photons will generally escape that atom. Whenever we talk about nuclear fission or fusion and comment about how you’re only getting a percent or less of the mass-energy out of the deal, that’s basically why: virtually all the interactions that produce them is basically just shuffling around the particle types inside with a little energy released externally, but when it shuffles all that into photons that’s a 100% conversion into a type of energy that can both escape the atom and be absorbed by other matter it runs into, like you. Neutrinos incidentally do have an anti-particle, the anti-neutrino, but neutrinos interact with virtually nothing so it’s not explosive the way we normally think of as anti-matter. Getting whacked by hordes of neutrinos or anti-neutrinos isn’t going to incinerate you, and a good thing too. We are all constantly penetrated by passing neutrinos, mostly from the Sun, but only in the rarest cases is there any change to us from that passing swarm. We also should note that things like protons and neutrons aren’t really made of just three quarks. If you’ve ever seen quark mass and compared it to a proton or neutron mass you’d notice that those up and down quarks only mass about 2.2 and 4.7 MeV each, about four and nine times an electron or positrons mass, whereas a proton or neutron is around 2000 times the electron’s mass, the neutron being a bit heavier because it has one up and two down quarks instead of two up and one down, a tiny mass difference. Only around 1 percent of their apparent mass is actually the mass of those quarks. The other energy is in gluons and we also have “sea quarksâ€, which are the virtual particles popping in and out of existence inside the nucleus all the time, the normal three quarks being known as valence quarks. That notion of stuff popping in and out of existence is worth keeping in mind because it’s a critical aspect of producing antimatter, since matter is popping in and out of existence all the time as virtual particles, and it always does so as a pair, a particle and its antiparticle. They generally annihilate near instantly, but by separating them we can produce and collect antimatter. I know this idea of seething stuff going in and out of existence tends to bug people but this is mostly a product of trying to view quantum entities as stable classic objects with a macroscopic analogue. Subatomic particles aren’t little balls, they’re stable or not-so-stable energy packets smeared across a place and only certain combinations are stable. At super-tiny time scales many more particles and paired particles can exist. Without virtual particles, many important aspects of our universe would not function at all, fusion inside stars being a prime example. Stellar fusion cannot proceed until some protons change into neutrons, but protons cannot change into neutrons except with the aid of very heavy W bosons, which are more massive than entire iron atoms, and therefore cannot be created as real particles in the not-super-high energy conditions inside normal stars. But as virtual particles, W bosons can be called into existence there, very very briefly. Quantum entities aren’t objects but more like patterns of energy, and only a handful of patterns don’t collapse, and there’s always the mirror-image patterns that are equally viable, the antiparticles. When those two meet they collapse and that energy forms something else, but that something is always popping out with its own mirror image, photons just happen to be their own mirror image. Related to these virtual particles is a virtual energy to spacetime. A little handful of space has some energy in it in addition to all the atoms or photons actually passing through it, and that base-level energy is constantly seething around forming a pattern and its anti-pattern and pretty much falling right into each other to recombine and vanish. As these were virtual patterns, they leave no residue of real energy. Every so often stable matter or energy will bump through one of those virtual interactions and something else will happen as that particle interacts with one of them and that’s essentially how all the various subatomic processes happen. But if you had a virtual electron-positron pop up inside a very strong electric field – and this has to be very strong because they’re really close and opposites attract – you could pull them apart and make new matter. This isn’t free energy though, you have to provide real energy in order to make the virtual pair become real. On their own, those base level energy fluctuations of spacetime always return to the zero level, hence all the talk of quantum fluctuations and the vacuum not really being a vacuum, but bubbling and seething with potential, or vacuum energy. It really is often easier, and reasonably accurate, to just think of it as a big soup of energy out of which some more packets of energy can sometimes linger as what we think of as particles for long times, which in particle terms can be anything from a trillionth of a trillionth of a second to trillions and trillions of years. Some energy configurations are more stable than others; those we call particles, but the vast majority aren’t stable at all. Anyway, this is not a particle physics lecture but we had to go over some of that to explain why it's so hard to make and store anti-matter, and why it’s so useful if we can. Which is to say, it is stupidly easy to make antimatter but it’s really hard to do it in a way that lets you grab those particles before they ram into something else and go away, which is a big issue for production and storage. Virtually all matter, at the molecular and macroscopic scale, is electrically neutral or very close to it. If you try to cram protons or electrons, or their anti-particles, into a box with just that one type in it, the amount of electric force they have would be massive. Electromagnetism is trillions of trillions of trillions of times stronger than gravity, so you can’t make a box full of protons or a box full of electrons because the repulsive force between them all is insane. Similarly you can’t make a beam of electrons or protons stay together because they’re trying to shove off each other into a widening cone, and if you’re mass producing anti-particles in some spot they’re all trying to shove off each other and scattering and running into other things that will blow them up. You need to produce them as charged particles in order to separate the matter and antimatter particles because they actively seek each out out if mixed together. But you need them to be mostly electrically neutral if you want to store them at some useful density. Not totally neutral though, so that you can actually move the stuff around electrically or magnetically. We might have one possible mode of production and manipulation suggested, like the Stellaser, by the fertile mind of Steve Nixon, a method that’s still a bit out there but maybe could be made to work. You’ve heard of using lasers as optical tweezers I’d imagine, and they’d be one way to manipulate these particles without electrostatics or magnetostatics, allowing us to play with electrically neutral antimatter. Since these things we call particles can be thought of as really being energy patterns with specific wave-states, we might be able to literally build them out of light, in the configuration and location of our choosing, using certain extensions of 3D holography. Essentially using a specialized waveguide to produce two equal and opposite interference patterns of intense light to pull the desired particle pair out of the quantum foam and tease them apart, be it an electron and positron or a proton and antiproton or a neutron and antineutron. Eventually even something much bigger like a molecule and its anti-molecule, which would be a lot easier to store at a desirable density. That’s pretty far out there and probably a topic worthy of its own episode, but deserves a mention. Particularly since your ideal antimatter for storage is something bigger and more stable than a gas of antihydrogen. Normally we talk about creating anti-hydrogen by just getting an antiproton and positron to link up but we’d infinitely prefer big macroscopic slabs or beads of some material like anti-iron, which you could easily store by old-fashioned magnetic levitation in a small vacuum compartment of some material that’s not going to get wrecked by a very occasional single atom annihilation, essentially a normal bit of radiation shielding material. There is a type of Titanium we believe is produced by white dwarf collisions and their resulting supernovas, called Titanium 44, which is highly radioactive and decays only by electron capture, then goes on to produce antimatter positrons. We see its telltale antimatter annihilation gamma ray signature near our crowded galactic core, but it is produced throughout the galaxy. Titanium 44 has a half-life of 60 years, but it is believed its half-life increases with ionization and becomes stable when fully ionized. It might not be antimatter itself, but may allow us to safely and more easily use its positron antimatter decay product in our matter world. Eventually we may send harvesters to collect Titanium 44 from white dwarf supernovae, or learn to produce it efficiently locally. Now on the production end in the more near-term and tested fashion, you’ve probably heard we need to dump many million of times more energy in to get antimatter out. We’ve been getting better at that, and it’s worth noting we don’t normally set up particle accelerators with mass production of antimatter in mind. They’re normally just particle experiments to find and measure exotic particles, not mass produce them. We’ve had design concepts for mass production for decades that were thought to be able to do more like 10,000:1, which sounds terribly inefficient but surprisingly would be very useful. Back in 1995, in his book “Indistinguishable from Magicâ€, Robert L. Forward suggested using a large solar array about 100 kilometers across with a power output of about 10 terawatts to produce about a gram of antimatter a day. Again, that’s inefficient as heck but we’ve talked before about possibly shading the Earth to cool it, and such a panel would help with that. Or to switch over to using power satellites to beam energy down to Earth, and since you always want more output capacity than you need and solar panels have no fuel they burn, you could use the surplus capacity or excess outside peak hours and days to run such antimatter factories. Similarly we’ve talked about the simplest of Dyson Spheres, Swarms of thin mirror power satellites, statites, or lagites englobing the Sun, which could be constructed using relatively little mass, exactly the sort of manufacturing a simple and early-design clanking self-replicating machine would excel at. Something like that built by such machines could probably be assembled over a vastly shorter timespan than it would take for human populations to reach the number needed to fill out a Dyson Swarm of habitats. Folks often ask what you’d do with all that power. Producing antimatter that way, even at 10,000:1 efficiency, is one example of what you could do, producing a few million tons of antimatter a day. After all, minus the ecliptic plane the planets are on, we don’t use any of that sunlight and it just goes to waste in the void, so we might as well get use out of it, even if it’s inefficient use; 1% of 1% is far better than zero, especially when talking about starting with 2 billion times more energy than received by the entire Earth. It's worth noting though that there are some natural sources of antimatter. Cosmic rays tend to produce it and we estimate about a kilogram of anti-protons passes through our solar system every second. We could potentially scoop it up from the upper atmospheres of any of the planets and the gas giants have a lot more than we are producing now. Saturn has about 250 micrograms produced each year. Still, that won’t get the job done for anything but scientific uses or for sending off tiny probes. Though if those tiny probes are von Neumann probes, self-replicators that can arrive at another star after making the journey at a high fraction of light speed and unpack and build stuff, like the interstellar laser highway system we’ve discussed using before to let ships run on rivers of light between stars. That’s another thing you can use the Sun’s excess power for. Our local natural sources just can’t be regarded as anything more than meager, but it is worth nothing that things like black holes and neutrons stars can spew antimatter out. They are essentially giant high-powered particle colliders with relativistic particle jets, so those might become antimatter farms in a distant future, and I say farm rather than mine because you could augment the process around them to fertilize production and harvest antimatter. In many cases antimatter production might simply be a byproduct of another process too. We talked about using surplus space-based solar power to run production a moment ago, but you might get antimatter as a byproduct of power production, too. Short of farming it in an extreme astrophysical setting, it’s not very likely anyone would ever come up with a way to economically power a civilization on antimatter, as even a high-efficiency method would still need more power input than the antimatter produced would release, but we have a concept called antimatter catalyzed fusion. Same as we can catalyze fusion in a hydrogen bomb by using a regular fission bomb to set it off, itself usually set off by conventional chemical explosives, you can catalyze fusion by using a tiny amount of antimatter. Current estimates say you need about a microgram of antimatter to trigger a thermonuclear detonation and it need not be a big one, making it rather ideal for things like pulsed-nuclear spaceships as we looked at in the episode “The Nuclear Optionâ€. Ideally we’d like a spaceship that used pure matter-antimatter reactions for fuel, but fusion driven ships are nothing to sneeze at and antimatter-catalyzed fusion might be a good way to do this. You could also potentially be using the power produced by the fusion event, which is much more than that released by the antimatter catalyst, to power more antimatter production. Producing your antimatter for this process while you’re in flight would be very handy, given the storage issues with antimatter which have been mentioned. We’ll get back to them a moment. First though, there is an alternate version of catalyzed fusion using muons rather than positrons, antiprotons or antineutrons. Muons are short-lived and much more massive versions of electrons, often generated in our upper atmosphere by cosmic ray proton collisions that first yield pions, which then decay into muons. You get hit by thousands every minute and they’ve got a good penetration value, they can bounce around a lot and this can be used to catalyze fusion in deuterium or deuterium and tritium. This is an amazing way to catalyze fusion, and to do it at room-temperature too, and this one isn’t theoretical, it’s been done in labs plenty of times for decades now. It also produces antimatter as a small but significant byproduct while it’s at it. However, it has got a couple problems. First, the muon will stick to an atom a bit less than 1% of the time it hits one so it only bounces around so many times igniting fusion events before it decays, and second, we’re quite inefficient at producing muons, much like antimatter. If we were better at producing muons efficiently, that alone might solve the problem, but it is possible we could set this up on a grander scale in some environments that were more hospitable to this process, such as the upper atmospheres of gas giants. Again as suggested by Steve Nixon, here are some methods of defeating the problems with getting power from Muon Catalyzed Fusion. Getting some fusion energy is easy, but getting useful net energy is not. First of all, the deuterium and/or tritium needs to be in a very dense form, so that many useful muon collisions will occur during the brief lifetime of each muon. That either means insanely high pressure, use of liquid isotopes of hydrogen, or both. The usual method has been bombarding cryogenic liquid deuterium with muons, and it works very well for warming the super-cold liquid, but that only consumes power, for turning the gas back to liquid. The problem is the liquid is made at a much colder temperature than the ambient temperature anywhere on Earth. That kind of refrigeration consumes a lot of energy. To turn this fusion into an energy source, the dense state must be achieved cheaply, and the warmed state must do net work, just like the Rankine Cycle using water and steam in a normal steam-electric generating station. Normally, like with any other gas, compressing hydrogen isotopes to high pressure as gases uses a lot of energy and generates a lot of waste heat, so that is not a productive path. BUT, if a very cold heatsink was available, like the middle-to-upper atmosphere of Neptune, then the gas could be compressed and even liquified using a relatively small amount of energy. Gas giants also contain vast amounts of deuterium. It can be separated from the other gases by any of several methods, before, during or after compression and liquefaction. By pumping that liquid deuterium up to fairly high pressure, which uses little energy since liquids are essentially incompressible, then injecting negative muons into it, the liquid will warm and partially boil at that high pressure. Then it can do work in a turbine, generating power. The slightly warm gas exiting the turbine will now contain a little helium, which can be removed in various ways while the deuterium fraction is recycled, cooled and compressed again. That leaves the problem of making the muons. And some antiprotons would be nice, we could export those. Antimatter is definitely worth the cost of hauling out of deep gravity wells. Some deuterium may also be exported. To make antiprotons, accelerate protons (atoms of normal hydrogen) to about 50 billion electron-volts, then smash those together with similar protons going the opposite direction around the accelerator. Result: a few proton-antiproton pairs, a lot of pions since they are the lightest mesons, and some energetic photons. The pions decay very quickly into muons, from which the negative muons are selected and sent into the fusion area. The energetic photons from all that can be used to reheat the warm deuterium after some in-turbine expansion, and/or used to further heat the high-pressure deuterium before the turbine. Waste heat from this heat engine is still rather warm compared to the atmosphere outside, so that heat plus waste heat from most of the other areas of this antiproton factory is transferred into one or more balloons filled with light hydrogen gas. That provides lifting force to hold the entire antiproton factory at the desired altitude in the sky of the gas giant. You then accumulate antiprotons until there are enough to make a shipment, then launch them into space, perhaps on a rocket using antiproton-catalyzed fusion of deuterium. An extremely large number of these antiproton factories can operate all at once, in the skies of many gas giants. Total production rate of antiprotons can be made rather high, plus deuterium and even some helium-3 can be exported. Otherwise those gases will sit there in those gas giants for billions or trillions of years, doing no good for anybody. I said a bit ago that it would be nice if you could produce your antimatter while in motion on a spaceship, and that brings us to the storage issue. We have a device called a Penning Trap that is basically just a magnetic field, usually inside a cylindrical body, that can keep particles with an electric charge confined within it instead of hitting the sides. Now the best we can do at the moment with these is keep stuff confined for about half an hour before the particle just happens to get a trajectory that isn’t confined enough and hits the side, but that can be dealt with by size and temperature. Antimatter we make now is very hot, it has a ton of kinetic energy when made by the processes we use, ultra-relativistic collisions, and such bottles aren’t big, which means it bounces around a ton of times in a short period. Double the size of the vessel and you double the lifespan of the stuff inside it since it has to cover more distance between bounces and interactions. Lower the temperature and you achieve similar. Cooling antimatter is rather tricky since at that scale cooling is achieved by slowing a particle down, which is usually via collisions with other stuff moving slower. But you could do this via an electric field or optical molasses, and also produce your antimatter at lower energies. As I mentioned before, we don’t really make the stuff with mass production in mind and your typical supercollider operates at particle temperatures far beyond the inside of any star’s core. This is an example where scale helps, and while antimatter’s portability is a big part of its value, so that we wouldn’t want giant Penning Traps, it’s perfectly fine to have an antimatter factory with hundreds of kilometers of length to be used to slow down or cool antimatter to be transferred into something smaller once that’s done. The same is the case for trying to build large chunks of antimatter, as pellets of something like anti-carbon or anti-iron or whichever that just had enough ionization to let you hold the pellet in magnetic levitation in a vacuum flask. Your default ideal storage device would be one with an equal mass as the antimatter within, since that becomes a self-contained device. Antimatter by itself produces no energy, anymore than regular matter does. What does the job is antimatter and an equal amount of matter, with both being converted into energy, and again a gram of the stuff is equivalent to a 43 kiloton atomic warhead, since 2 grams are destroyed. And if it’s a weapon you don’t have to worry about a source of matter because that’s provided by the target it strikes. Your typical bullet has a mass of 20 to 40 grams, though varying widely on caliber, which means a bullet of antimatter can produce an explosion big enough that only someone using a very long-range rifle wouldn’t be in the blast zone of their own weapon. You could obviously do much smaller bullets or ones with less antimatter in them, and if you’re good at manipulating and storing the stuff, it also gives you an alternative to chemical-powered firearms. While electromagnetic rail guns are a popular idea, getting those compact and high powered enough to be man-portable is no easy thing, whereas antimatter is as superior a substitute for gunpowder as it is rocket fuel and would allow you to fire shots at very high speed, only limited by friction in the air, and up in space it allows weapons to move at relativistic speeds as an alternative to laser and particle beam weaponry. Needless to say it lets you pack quite a warhead into the shot too. Which raises the physical security issue. Now, while I and others have raised the concern that a society might collapse simply from having technologies so dangerous and easy to produce that any lone lunatic could manufacture a doomsday device in their basement, and while antimatter is a common example, in practice it’s very unlikely it would be. You would not mass produce antimatter on planets in all likelihood for the inefficiency and waste heat reasons we outlined earlier, but it’s also a power glutton and that makes it easy to detect if someone is making it on a planet. At best you’re producing it by using the same amount of energy as it will eventually produce and in all probability even the most efficient process is going to be an order of magnitude less than whatever fuel and power system you’re using to make it. It’s not free energy, and some would-be terrorist is going to be given away by the giant electric bill and huge thermal blossom at their facility. You’re going to notice someone using ten times the normal electric consumption they should be and if that were a regular American household, that roughly 40 billion joules they’d normally use a year is only going to net them the equivalent of 10 tons of TNT, nothing to laugh at but they’d need thousands of years at that rate to get it up to atomic bomb levels of explosives. You probably could get away with producing it a couple orders of magnitude faster and you don’t need a gram of antimatter to wreak nuclear havoc. We talk about suitcase nuclear bombs but the antimatter equivalent is a pen-sized bomb or even a pinhead nuke, just depending on how small your Penning Trap or alternative storage method is. And let’s not forget it can be used as a fusion catalyst. If a milligram of antimatter is suddenly injected into 1 liter of liquid deuterium, the results may be very like a nuke, but with no need for fissionables or even high explosives to kick off the bang. Now, that said, you’d almost have to smuggle something like that in from offworld for anything in the kiloton or higher explosive range unless a very big group or country was involved to obscure your power usage or let you siphon from their own stores, and antimatter is the sort of thing you’d store in quantities as small as you could for fear of accidents and as large as you needed to ensure efficient and solid security on it, while being economical with your security assets. I don’t think you’d store it on-planet in quantities big enough to go off as a nuke when you could distribute it to more the scale we’d associate to a modern fuel depot going up in an explosion. That smuggling issue is not quite as bad as the tiny size implies. First, a pen is not a small thing in terms of people or cargo going through ports of entry, and if we’re talking spaceports you process through before going down to Earth, then we’re probably talking pretty high tech scanning. I don’t think you could hide even a small hollow and magnetic cavity that was storing more than a milligram, or even micrograms, just from the kinds of scanners we can make now, especially if those are being run by fairly decent AI analyzing the scans such as those we’re starting to employ in a lot of medical scanning. A milligram isn’t anything to sneeze at either but it’s no worse than a large truck bomb, at least as a pure antimatter bomb, the fusion catalyst option is worse. Speaking of those scanners though, one example is an MRI, a Magnetic Resonance Imaging device, key word there being ‘magnetic’. Penning traps or other magnetic confinement systems rely on very carefully keeping antimatter magnetically penned up, and disrupting that magnetic field is going to have explosive results. It’s also a defense against antimatter weaponry, like torpedoes launched by spaceships or orbital platforms, since they could hit the incoming devices with magnetic bursts as an alternative to shooting them down. You proof such devices against that by either employing magnetic shielding or keeping the antimatter inside very, very cold so that the particles inside aren’t bouncing around fast and it will take a little time to go off, and you counter that, for hidden bombs, with quarantine periods. We also don’t have any materials that are much good at shielding from magnetic fields and those all rely on thickness, so barring some advanced metamaterial that let you shield very strongly against magnetic fields and with a very thin layer of shielding, you’re going to be able to detonate hidden bombs with your scanner. Of course we might get those magnetic metamaterials in the not-to-distant future, see our metamaterials episode for more discussion of that, which might be problematic but on the bright side might also be useful for storing or making antimatter too, amongst many other great applications. We also don’t want to think only in modern terms when it comes to detection, it’s entirely possible the customs and border security in the future will be a trillion tiny little robots that go into someone looking around up-close and personal, scanning for dangerous viruses, mysterious microscopic cavities in bones with explosives or equipment in them, and so on. Of course, if they find it, that person might detonate themselves, as would occur with the magnetic scan. Now losing a spaceport or city security outpost to such a bomb is no laughing matter but you could do small and isolated ones and potentially even telepresence for the folks manning it, so they were far away from the worksite while scanning people. Also, antimatter is not infinitely powerful, even an entire kilogram of the stuff going off inside a tiny space station in high orbit is only going to get a fairly tiny amount of your planetary orbital swarm and the real danger there would be setting off a Kessler Syndrome event, see Orbital Infrastructure for more discussion of that. We also might be able to get around some of the accidental explosions by not employing normal matter. I suggested big slabs of anti-materials like anti-iron earlier, because it’s less of a containment problem than anti-hydrogen gas if you can make it, but every particle has anti-particles and that includes things not made out of up and down quarks, like strange or charmed matter. You might make stable atoms with those types of quarks in them and others with their anti-particles and use them as your antimatter power source, since they can only annihilate with each other and strange and charmed quarks aren’t exactly hanging around our solar system in abundance. Needless to say, once we can start producing more of it and turning our minds to dealing with it, we may come up with all sorts of other safety mechanisms for storage. So, it’s quite a security issue but not a boogeyman and probably rather manageable, like most security issues arising from new technology. It’s very useful stuff too, so as you get better at producing and storing it, you figure out what level of usage is safe from accident or malign intent and employ that. Obviously the big use besides weapons is spaceship fuel, because it’s compact in so many ways. There is no better rocket fuel than antimatter, it outperforms even Hawking Radiation drives on micro-blackholes and is easier to make small ships out of. The only rival would be light stored inside a box that was a perfect mirror, since that’s also a mass-energy level device and is essentially what antimatter is doing. You don’t need a high-tech spaceship to get near light speed if antimatter is your fuel, and it's also an amazing fuel at any other speed too. There’s no complexity in its actual use, just the making and handling parts, you combine it with matter and you get a ton of energy. But we don’t always need a ton of energy and that’s where it has some novel applications. Given the security risks it sounds absurd to have cars or appliances powered by antimatter, but keep in mind that it’s all about quantity. Tiny machines with microscopic penning traps, or even nanoscopic ones, may be an ideal compact power source for very long periods, at least for lower energy antimatter like positrons, keeping in mind that antimatter is about a billion times more energy dense than the typical chemical fuel and even more so than our best modern batteries, and probably can be made tinier than a gas engine. If we were using some exotic matter, like strange quarks, we might not even have to worry about an explosion if the containment got ruptured. And again, if you’re substituting for a normal modern fuel, there’s no more energy there than that fuel already contains if it ruptures its tank and goes boom, indeed rather less since you need to pay extra energy to tote your fuel and associated equipment around, which is a very big deal for things moving fast like airplanes and especially like spaceships. That is definitely a long way off, and quite probably never, but I really wouldn’t be too surprised if a time machine to the 23rd century saw folks walking around with tiny bits of antimatter running their ultra-smartphone or personal cybernetics. That explosion issue is also less important for military application than regular folks walking around on their regular daily business, so might see first use in things like military vehicles, armored exoskeletons, giant mecha or war robots, or power armor. In the short term though, antimatter technology is already in use. Beta-decay atomic batteries may see regular usage in coming decades and its medical applications are already there, I mentioned MRI scans earlier but we also have PET Scans, and that is short for Positron Emission Tomography, antimatter already being used to save lives, and we’ve been experimenting with using anti-protons for cancer treatments too. Back in the early days of sci-fi we often heard folks say we were entering the nuclear age, but antimatter is far more powerful than fission or fusion, so it might be that the future isn’t nuclear, but antimatter. Dangerous stuff, but if you don’t antimind, it doesn’t antimatter. So we covered a lot of particle physics today, and it can be a confusing topic considering how counterintuitive quantum mechanics often feels. If you’d like to learn more about Quantum Mechanics, then I’d recommend Brilliant. Brilliant has an excellent course on Quantum Objects that will walk you through not just the basics of Quantum, but even fairly advanced concepts, and do so in an interactive fashion. In a time when more folks are embracing online education, Brilliant’s focus on fun and interactive methods makes them a great choice, whether you’re a student, a parent trying to enhance your kid’s education, a professional brushing up on cutting-edge topics, or someone who just wants to use this time to understand the world better, you should check out Brilliant. Try adding some learning structure to your day by setting a goal to improve yourself, and then work at that goal just a little bit every day. Brilliant makes that possible with interactive explorations and a mobile app that you can take with you wherever you are. If you are naturally curious, want to build your problem-solving skills, or need to develop confidence in your analytical abilities, then get Brilliant Premium to learn something new. Brilliant’s thought-provoking math, science, and computer science content helps guide you to mastery by taking complex concepts and breaking them up into bite-sized understandable chunks. You'll start by having fun with their interactive explorations, over time you'll be amazed at what you can accomplish. If you’d like to learn more science, math, and computer science, and want to do it at your own pace and from the comfort of your own home, go to brilliant.org/IsaacArthur and try it out for free. So next week we’ll be returning to the alien civilizations series to consider the notion of aliens who come in peace, and actually mean it, in Benevolent Aliens. Then we’ll close out the month of May with our Monthly Livestream Q&A in our new SFIA studio, on Sunday May 31st. We’ll then jump into June & Summer by returning to Jupiter to contemplate the idea of making Jupiter into another Sun, and look at some techniques for how we might do that and why we might want to, in Summer on Jupiter. For alerts when those and other episodes come out make sure to subscribe to the channel, and if you enjoyed this episode, hit the like button and share it with others. And if you’d like to support future episodes, you can support the show on Patreon or visit our website, IsaacArthur.net, to donate to the channel, see our list of episodes or book recommendations, or buy some awesome SFIA merchandise. Until next time, thanks for watching, and have a great week. Arcologies Today will be looking at Arcologies, a sort of mix of skyscraper and self-sufficient habitat. And will be exploring this idea, where it came from, and what it implies for human civilization. The first thing to understand is that Arcology has essentially developed two different meanings. The original one, where the name derived from, was essentially the idea of self-contained ecologically sustainable communities. The word Arcology is a portmanteau of the words Architecture and Ecology and that accurately describes the original intent. In this context there’s no special implication of it being a single giant building, though it wasn’t unusual for it be a community under a dome, or linked together. There’s no need for such communities to be isolated from trade but the assumption is they are designed to be at least minimally self-sufficient in terms of things like food, in contrast to a classic cities or castles that certainly didn’t grow their own food on site. The concept of a single massive building is the more modern notion, and as best as I can tell the enormous skyscraper approach was popularized by the classic game SimCity 2000. This portrayal almost inevitably shows the tower back-dropped against a major metropolis where it is being contrasted against it by its sheer size and usually a lot of plants and greenery in evidence, though it tends to imply that if that greenery is the real food source for the inhabitants the artist has wildly inaccurate notions of how much space growing foods takes. Traditionally an acre could feed a single person, though just barely, but modern farming does about an order of magnitude better, and climate controlled greenhouses doing hydroponics especially if you can do layered setups supplemented with red light, which is the primary one used for photosynthesis, can bump that up another order of magnitude. So it is actually conceivable to grow enough food for one person on the equivalent space of one large apartment or the basement of a house. But most apartments of that size have more than one occupant, and obviously you can’t use that space for living in and dedicated growth, particularly if you’re optimizing your growing space with red light, carbon dioxide, and heightened heat and humidity. Also skyscrapers cost something like $1000 a square foot, meaning your growing space for one person would cost something like a million dollars. Nor would this include much excess food, feed for meat animals, or for non-food elements like cotton for textiles, wood for lumber, or biofuels for fuel or plastics. We’ve played with these numbers before in the fusion video and some of our looks at space habitats and ships and I’ve usually found that a value of about 2000 square feet or 200 square meters is a pretty decent size with lots of padding and rounding up. Keep that number, rounded and somewhat arbitrary that it is, in mind for later. Most Arcology art that I’ve seen seems to just have the walls covered with plants and maybe some more inside getting non-optimal lighting. And the image those tend to paint, to me anyway, is essentially an over-sized building with houseplants and gardens, which is hardly revolutionary. Our cities have featured plants for as long as we’ve had cities and keeping a small herb garden out back, on a windowsill, or on your roof was a classic way of slightly supplementing your diet or improving the taste of your meals while helping to mask all the odors associated to human habitation especially prior to the invention of modern plumbing and sanitation. There’s nothing terribly revolutionary about growing plants in or around buildings, but if you actually want to feed the inhabitants primarily off those you not only need a lot more space devoted to it but to adopt some pretty intensive measures to get those yields, as I just mentioned. I’ve never really considered either vision of Arcologies terribly accurate though, and I thought the cover art was a lot more accurate to the real concept. This is the first time I’ve ever had the cover to a video on hand during the writing phase of a video, usually all the art comes well after the scripts are done so it’s nice to have one on hand while I’m writing for a change, admittedly this is script draft #5 at the moment, but I was especially taken with the cover Jakub designed since it nailed the concept on the head so much better than most representations I’ve seen. Out goes the contrast to existing metropolises, where every effort is made to show how immense these structures are, and we’re not impressed by that scale anyway since the megastructures series has shown us constructs so large even the smallest of them next to a giant stadium would look like a rolling pin next to a peanut. In comes the more proper image of giant buildings integrated into a more natural setting but one with mankind’s handprint on it in the forms of the hexagonal grid below. Arcologies are supposed to replace cities, so while you would expect early ones to sit next to a cityscape that portrayal shows us arcologies the same way sticking a model-T next to a bunch of horse drawn carriages show us a modern cars and roads. This video is essentially a two parter with next week’s video looking at the notion of the entire planet being subsumed into one immense city and I’m forever trying to explain that the sort of dystopian, packed concrete forest shown to us in most examples of that is just off the mark. Later in the video we’ll walk through an example Arcology only about as tall a tallest skyscrapers nowadays and not all that wide and we’ll see how just having one these poking out of the forests every couple miles would let you easily house dozens of times our currently population, and see that heat not space is the real bottleneck to further growth. So this image of them towering on their own or in small clusters scattered throughout forest and farmland is far more accurate. Now this doesn’t mean an Arcology can’t have all its food production done inside instead, but to do that you almost have to have fusion and ultra-cheap, ultra-durable construction in terms of height too, and we need to talk a bit about Vertical Farming to explain that. Vertical Farming has become quite a craze in recent years and I say craze with the full derogatory intent because it never makes any sort of economic sense to have your food supply, which takes a lot of space, grown inside skyscrapers, which often cost thousands of times more per foot of area than farmland does, and which really has few advantages economically or ecologically if you’ve got to run yourself on fossils fuels or solar power. In the absence of fusion, to light an acre of farmland up with replicated sunlight is going to require a few million watts of electricity running for a couple thousand hours a crop, so that even if you’re very miserly and efficient with your power supply you are burning millions of kilowatt-hours, and hundreds of thousands of dollars, to light up one acre per crop yield. It’s only when you have an actual alternative to sunlight that this becomes viable. And just as reminder, if you’re in doors right now with light coming in through the window or from a light bulb, it’s not half as bright as the noon time sun, it’s more like a hundredth or a thousandth. The noon time sun is about 100 Watts per square foot, a 100 Watts light bulb usually only produces about 10 Watts of visible light, and that’s being spread over a hundred or more square feet of floor and wall. The only reason LED lights, which produce strictly in the visible range, are even vaguely viable is that the super-majority of the sun’s light is not usable in photosynthesis, whereas LEDs can be tailored to emit a matching spectrum, and that plant’s can’t use most of the noon time sun light. So with LEDs you don’t need 100 Watts of sunlight per square foot and can get the same effect from maybe 5 watts of tailored light instead, less in most cases. That’s still prohibitively expensive, without fusion, but it also means you can light up a whole planet’s worth of surface area inside buildings without roasting the planet since you’re only adding 5% more heat to the setup, and we’ve discussed before some way of cooling planets and will look at that more in the follow up video. So that whole equation changes if you’ve got fusion. When you can exactly control the amount of and frequency of light and you control humidity, temperature, nutrient supply, the works, you can squeeze a lot of food out of an area and to the point that a large basement could produce the food for an entire family living in that house. Cheap, sustainable power is a huge game changer, but so is ultra-cheap construction and automation. In that sort of context a micro-arcology, a cabin in the woods, on first glance could look like any other, only you’d be surprised how lush and dense that forest was, and down in the basement there’s a couple level of hydroponics growing food and at night time little robots scurry out quietly to fertilize and tend to the forest, to harvest a bit of biomass, to water things, and so on. The notion of polyculture, which is mixing crops to optimize yields, is not very cost efficient currently because it can be pretty manpower intensive. Like with fusion, the equation changes when you’ve got better robots. The big green grass lawn that is a staple of suburban America is a staple because its not very time consuming compared to elaborate gardens. We already see robots replacing lawn mowers and vacuums, when you’ve got robots cheap and sophisticated enough to scuttle around on orders from your house computer pruning trees and watering and weeding gardens you would expect to see that replace the green lawn setup because it’s just an initial capital outlay plus the occasional maintenance or replacement of robot when your dog or cat mauls it, and you’d see a lot more fresh produce being homegrown when they can just scuttle in from your garden or greenhouse and stick the stuff in the fridge. This is every bit as much Arcology as giant towers are. So arcologies as a concept is just self-contained, self-supporting habitats. That could include everything from domed cities on the Moon or Mars or the giant rotating habitats we’ve previously discussed, to tower buildings where everything is grown inside, all the way down to a small cabin in the woods. They needn’t be isolated from trade but the notion is minimalist, because you’re trying to do most of your consumption from local production. But the giant building, if you do have fusion, can be one where everything is done not just nearby but totally inside the structure. Such structures could extend deep underground and high up into the air, and the control factors on their size run into two interesting problems. The first is strictly psychological, most folks would want a window view, so you aim to have hydroponics and factories and storage deep inside, the reverse of if you need sunlight for your food where the outside edge needs to be given over to hydroponics. In a fusion-powered setup you just have all these endless rooms lit mostly with red light to maximize photosynthesis with each room devoted to that being endless shelves of white or reflective material probably sealed off and mostly tended by robots. In both cases you recycle your water, sewage, and air supply through there. The other problem is called the Elevator Conundrum. The elevator conundrum is a term used to describe the problem that while having elevators allows for tall buildings, they also limit the height of tall buildings since you need to provide more elevators for each floor you add on. Doubling the height of building means doubling the people in it and slightly more than doubling the number of elevator shafts you need since those elevators also need longer travel times for the extra floors. Each shaft takes the same place up on each floor, so if you double your elevators you’re doubling the portion of your building given over to it, and again probably a decent amount more since you need those elevators to spend more time moving to go from top to bottom. This is a big deal with tall buildings, just as a quick example, if we needed 10% of the floor area to service a ten story building, say one that was 100x100 feet wide, 10,000 square feet per floor or 100,000 feet total, we’d have 10,000 square feet just devoted to elevators leaving only 90,000 for proper use. If we doubled that we’d needs 20% for elevators and our 200,000 square feet would need 40,000 for elevators and so we get 160,000 for other purposes, practically speaking probably less too from compensating for longer travel times. We doubled the area, we almost certainly more than doubled the construction cost, and yet we go from 90 to 160,000 usable footage and only got 78% more area. Adding ten more stories on, jumping to 30 floors and 300,000 total feet, and 30% devoted to elevators, give us only 210,000 feet for use, jumping to 40 stories, and 40% usable area, would give us only 240,000 usable square feet and at 50 stories we only get 250,000 feet, and at 60 stories we’re actually back down to 240,000 feet, and at 70 stories, 210,000. So at a certain point you’re not even getting diminishing returns as you get less and less area from each new level while it costs far more to build each new level, with the elevator conundrum you eventually get a point where you actually have less usable area. And there’s similar 2D problems with roads in cities too. Needless to say there are a lot of partial solutions to these problems, double decker elevators, express and dedicated elevators, dispatching techniques and so on. And it’s quite a fascinating problem with a lot of math, but interestingly arcologies partially get around it. An Arcology being essentially self-contained you have a lot of low traffic areas and a much lower population per square foot ideally. Remember early I said you’d need about 1-2000 square feet per person just for hydroponics, which doesn’t really need an elevator most days, whereas that’s a quite comfortable family sized apartment. You can also get away with a lot more levels because the first floor is no longer the primary destination for instance, and because there’s just more space per person. This doesn’t eliminate the elevator conundrum but it mitigates it an awful lot, and there’s never much point building higher than that would be a genuine concern for because you can always go wider instead and as we’ll see in the Ecumenopolis video even if you do every foot of your land and sea with arcologies, so that all that’s left is to go up, you hit the heat wall long before the elevator conundrum becomes critical. Also looking at an Arcology, where construction needs to be cheap enough, either to build or maintain, that devoting the majority of it to food production is viable, does require us to discard the notion of cramped buildings entirely. Arcologies are just something you don’t even build unless you’ve got the ability to make pretty spacious buildings in terms of individual area per person. We’ll look at that more in Ecumenpolis video but in short form, as long as you have to do your farming basically one level high, whether you’re doing that in land-inefficient but labor and cost-efficient open air farming or everything is being done in greenhouses, you just don’t need a lot of verticality to most of your buildings because it doesn’t benefit you. Human living, working, and shopping areas just don’t take up much real space. You look at Hong Kong and New York, the two cities with the most skyscapers, not only is neither of them even in the top 40 most densely populated cities, with the most dense, Manilla, barely having 50 skyscrapers, but neither takes up much actual land area even though most of the buildings aren’t even shorter high rises let alone tall skyscapers. Same as folks who don’t live in the country often forget how immense farms are, with larger ones often being bigger than cities, folks who mostly see metropolises on TV or going in for a shopping trip tend to forget that only a tiny fraction of the buildings in even the largest metropolises are 4 stories high or more, and only a small portion of those are skyscrapers. You might need all of an entire continent devoted to feeding our current population but you could comfortably house the entire population in one or two story suburban style micro-mansions without even denting your total area. Suburban housing densities of 14,000 people a square mile is not even a little cramped, that’s like a quarter-acre lot per family, and that would fit the whole human population into half a million square miles. Which sounds huge but is about the size of Spain. So you only start housing most of your population in tall towers when building them has gotten so cheap per square foot that you can plausibly start thinking about doing most of your farming indoors too. We might build an Arcology principally for the prestige, same as building the tallest building, but don’t ever expect them to become normal things a significant fraction of the population lives in until we can actually grow food economically indoors. It just couldn’t happen. If it did though, if we could do it economically, you could toss out the cramped apartment concept because living area would have had to have gotten proportionally a lot cheaper. And you can overlap growing area with living space too as your fish tank becomes part of your water recycling and produces food, your hallways being lit have plants growing on the sides, maybe your window curtains are actually a mesh fruit vines grow in, that sort of idea. Things we mostly don’t do now not because of space so much as time, doing them requires time and attention after all. Now there’s no optimal arrangement or size for these yet, so let’s walk through a conceptually and mathematically simple one. We’d previously said 1-2000 square feet was probably enough for food but let’s pad that out and remember we need other space too, and that we’re aiming for luxury and spaciousness. We don’t dystopia much on this channel. Let’s say an Arcology needed to devote 10,000 square feet to each person, and that includes not just living area but all the shops, farms, elevators, warehouses, public buildings, offices, and factories you’d need. You want to cram everyone into a monolithic tower you might as well give them a lot of breathing space. And let’s assume a population of 5000 per Arcology, also not entirely arbitrary, many places like my own state of Ohio use 5000 people as the official transition number from village to city and it happens be a value we often use for colony considerations in terms of both Dunbar’s number and minimum gene-pool to avoid genetic bottlenecking. Means you can have a specialist in almost every field living on site, and more than one of most. Means you can hypothetically know everyone in your own tower but is still big enough you can easily avoid people you don’t like. Means school class sizes don’t have three or four people, or three or four thousand, per grade. 5000 is a good community size, it allows a lot of independence yet still massively benefits from cordial relations and trade with neighbors. We could go bigger or smaller but it’s a solid number and a mathematically convenient one. So how much space is that? 5000 people needing an average of 10,000 square feet a piece for all their living, working, storage, recreation, and farming needs? Well its 50 million square feet, just under 2 square miles, about 4.6 square kilometers, just under a thousand acres or 500 Hectares. If we turn that into a 100 story high cylindrical building that would mean each circular floor needed to have half a million square feet and a radius of 400 feet. That incidentally is just under 3 times larger than the world-recorder holder, China’s New Century Global Center, in floor area, 8 times bigger than the Pentagon, and 15 times bigger than Khalifa Tower in Dubai, which is 154 levels high. All of these are deigned to either house or be workspace for a lot more than 5000 people, but remember this is all inclusive. It’s your parks and shops and factories and farms too. Now we don’t really think of cylinders or circular floors as the optimum design for window space, in fact it is the exact opposite, the shape which minimizes that exterior surface per volume, but the structure I’ve just described still has 2500 feet of circumference times 100 levels, or 250,000 feet of possible windows, or 50 feet per person for a population of 5000. That’s a lot of windows, especially considering most people prefer to live with someone else. We usually put the US coastline as being just under 100,000 miles, so if everyone lived in one of these and they only existed on the coast and only were spaced one per mile of coast you’d be able to pack about half a billion people into them, the population of the entire North American Continent, and leave the whole remainder of the continent over to forest if you wanted. If you just put one per square mile over the whole continent, keeping in mind that these only have a diameter of a sixth or seventh of that and would take up only a few percent of that square mile, you’d have ten million of these things with 50 billion people living in them, just in North America. Of course that would include tundra but an Arcology works just fine in tundra, desert, or ocean, or frankly on the moon, though they can generate a lot heat and would be harder to cool there. We’ll look at that issue and maximum packing in Ecumenpolis but its kind of key to understand that this concept of larger human populations living in dystopian trash dumps and eating Soylent Green is just a figment of over-population concepts from earlier science fiction. If you’ve got the power, either by fusion or secondhand fusion by solar, your real control factor is waste heat, not space, not food, and certainly not how many forests you can pave over. We’ll talk about that more next time too. Now you can builder these wider, you can build them taller, but if you’re a regular on this channel it seems pretty silly to try to impress people with sheer size. Last week we were talking about Matrioshka Brains and those can make classic Dyson Spheres look small and those are a billion times bigger than a planet, so some ten mile high building is not exactly over-awing at this point. In contrast the Arcology I just described is quite tiny and it’s still so large that if it wanted to have that central atrium a lot of skyscrapers go for with some trees in it, you could keep a full grown redwood in it. Nothing is really stopping you, besides maybe the elevator conundrum, from building these things so they stretch a mile underground and poke up into the upper atmosphere either. But larger arcologies, pretty much anything bigger than our 5000 person one I outlined, start needing ventilation, cooling, and transport networks built into them that are best compared to the human arterial or nervous networks. One reason you’d want to build them near a coast besides the view, much like a power plant, which would presumably be in the basement of one of these anyway, you’d need to suck in a lot of water to cool the places, and that can have positive effects on the local ecology too if done right. For that matter a lot of things can be done when you’ve got cheap power and automation that boost local ecologies. I talked before about the notion of vertical reefs in the oceans, just having fusion powered strings of light emitting at a photosynthesis optimized spectrum of light, to let plants grow far more abundantly and far deeper in the ocean, and you can do something similar on land too if you’ve got fusion, making your forest areas much taller and lusher by supplementing natural light with some photosynthetic calibrated red light and watering systems and fertilizer. There’s obviously a heat issue with something like that but it’s actually pretty minimal and considering some of the leviathan structures we’ve discussed elsewhere in the series, setting up solar shades between us and the sun that only blocked infrared light, which is again most of the sun’s emissions, would let you massively boost the amount of heat you could make on Earth without any ramifications to the ecology or aesthetics. Agriculture probably seems pretty boring compared to some of the subjects we look at on this channel and that’s probably why it tends to be a huge gaping hole in a lot of science fiction and futurism, fantasy too for that matter. Where you get your food from and how much food you can squeeze out of an area and how much labor that takes is a very big deal. These days we tend to grow crops as one giant field of all the same thing. The preferred way is polyculture where many different things are being grown to maximize the overall yield. That is more efficient, in terms of land or raw energy. What it isn’t more efficient in is equipment and manpower. Corn and wheat let you spew out a ton of calories from a large spot with very little human labor. That’s why they’re so cheap, and part of why things like strawberries are so expensive since we still need actual humans to do the picking. One man with a tractor can tend hundreds of acres of cereal crops while it can take the equivalent of an entire man year of labor to pick one acre of strawberries, which can actually yield a higher weight per acre than stuff like corn, albeit most of that weight is water not calories. We’ve a lot of crops that give much better yields in terms of calories than our staple crops but just take too much manpower to produce cheaply. It’s the human time, or the cost of machinery, which is our production bottleneck. We need those people for other tasks. That’s why we don’t just dome over every last drop of growing land, even though doing so would hugely increase yields and save huge amounts of water. We can still spend less time per calorie yielded by open air farming and have more than sufficient land to feed the population that way. As the dynamic shifts, either because we have more people than open air farming can support so have to go for more time-intensive but calorie-intensive production, or we get better robots, or we can spew out polycarbonate greenhouse sheeting for pennies on the dollar, our farms will begin shifting and probably our diet too. Many luxury crops that require a lot manpower to produce or have very touchy growing conditions would become more common and more to the point you can adapt elements of polyculture into industrial scale farming. And it wouldn’t always need to be robots either, I remember an example from Gregory Benford’s Galactic Center Series, coincidentally the earliest book I know of to reference arcologies by name, where they’d gene-tweaked their ants to go plant and harvest their corn, dutifully taking it kernel by kernel to silos and taking their share of the crop back to the hive. They didn’t use robots because robots were the bad guys in that series. Still while robotics is great stuff genetic engineering has its options too, for instance finding a way to make plants able to run on infrared light or green light too. Genetic Engineering like robotics is one of those controversial topics that some folks are fine with and others hate but I wanted to toss it out there as a reminder there’s lots of options. Most livestock tend to be inefficient grazers, trampling and ruining as much as they eat so if you could tweak them or the things they’re eating to avoid that for instance you get twice your yield. Arcology is a pretty broad-spectrum concept as I’ve been trying to emphasize and it really does extend across a lot of topics and disciplines and you try to fit the right one for what you want, what you can do, and what you’re willing to do. There are these giant climate-controlled warehouses where we grow lettuce for instance where they plant the suckers on little rafts on one end and pick them down on the other end and it just floats through like a slow conveyor belt, and you can expand the rafts the seedlings are on so you’re not wasting sunlight on them when they’re small. It’s not hard for me to imagine adapting that sort of concept to feeding livestock, like some big turf wheel that comes out at the trough and rolls slowly around through compact chambers spraying it with light and nutrients and rotating through like a conveyor belt over the course of a week. And there’s no reason you can’t double-dip on that to be raising fish off the water system being used or sucking the methane the cows are producing off be used as feedstock for fertilizer or plastics too. Again our bottleneck is a manpower and brainpower thing and increased automation, increased population, and so on really changes the playing field. That’s a topic we’ll be exploring more in the follow-up video on Ecumenopolises, where we’ll continue to blast away at this sort of Malthusian Apocalypse Myth that always seems so fixated on portraying humans and industrialized civilization as either intensely sterile or filthy places, and try to integrate how science and technology can allow more Eden-like setups without needing to decrease how many people we have and quite the opposite, actually have more people enjoying a higher standard of living without having to sacrifice many of things that we tend to feel are very important to who we are too. Lot of concepts today, as we tinkered with the classic image of the giant super skyscraper Arcology, and more next time, make sure to subscribe to the channel if you want alerts when that and other videos come out. If you enjoyed the video, please hit the like button, share the video with others, and if you want to support the channel it is on Patreon. As always, questions and comments are welcome, and you can explore other neat concepts like this by click on any of these video playlists. Thanks for watching, and have a great day! This video is sponsored by CuriosityStream. Get access to my streaming video service, Nebula, when you sign up for CuriosityStream using the link in the description. 66 million years ago the world was changed forever when an Asteroid only the size of a mountain struck Earth and wiped out the dinosaurs. It could happen again, any day, so what could we do to stop it? The primary current theory for what ended the dinosaurs was a massive asteroid, and it wasn’t the first or last time one struck our world with earth-shattering consequences. Indeed current theory also says a truly massive asteroid or dwarf planet early in our planet’s history struck us and threw much of our crust and mantle into orbit, debris from which later formed our atypically large moon. When thinking of calamities it is worth remembering that we ourselves probably would not exist except for that moon-generating event-- and we’d still be rodents if not for the one that got the dinosaurs-- so they can be beneficial for everyone but the folks on the receiving end… though that may not be the case for more advanced civilizations who may consider an incoming asteroid quite a boon. Those two events, the dinosaur-killer and moon-maker, are hardly the only major impacts we’ve had. The latter was so enormous there is no crater for it, it erased any events before it occurred, but we have hundreds of major craters we’ve found thus far and more doubtless we will find or that were erased by time. We’ve a crater in South Africa, estimated at 2 billion years of age, that is twice as big as the one from 66 million years ago that struck the Yucatan, and three more with craters over a 100 kilometers wide, with dozens in the tens of kilometers width. The largest known event in human times was about a million years ago in Ghana in Africa, and left a crater 10 kilometers wide, and another larger one in Kazakhstan also around a million years back at 14 kilometers. To give a scale, we usually say the energy release to form a crater roughly goes with the cube of the diameter, and that a one megaton nuke would leave a crater about a kilometer wide. So one 10 kilometers wide would be the equivalent of 10-cubed or 1000 megatons, essentially our cold-war arsenal, whereas one 100 kilometers wide would be a 100-cubed or a million Megaton blast. Those two about a million years back could each have been strong enough to cause major climatic events. Since then we’ve had many more that would dwarf a typical nuclear explosion, and while hardly civilization toppling events at a planetary scale, such an impact in modern times would likely be ruinous for the nation it landed in and potentially have disastrous economic consequences planet-wide. So, they are not rare, though the bigger you go the less common they are, and they are a thing to worry over. Particularly as there are probably over a million objects in our asteroid belt alone big enough to cause those kinds of impacts that would be civilization-toppling, and thousands that could cause mass-extinction. It is also all a statistics game, it is unlikely that anything that would even wipe out a city, let alone a planet, would strike Earth in the next thousand years but not super unlikely either. We are not talking lottery-odds, especially for city-destroyers. We’ll be talking today about how to detect and prevent or destroy such asteroids coming toward Earth. We also need to remember that this is the same technology that can permit malicious asteroid attack, someone nudging an asteroid into a collision course with Earth or even some accident in asteroid mining operations causing scatter collisions and perturbations that nudged many objects onto dangerous new trajectories. Now asteroids are not an ideal attack method because they are slow and easy to detect compared to something like a “Rod From God†or it’s big brother, the relativistic kill missile, nor would you tend to miss someone setting of the sorts of explosive or propellant needed to move one onto an attack vector, but it is an option and moreover, any number of asteroid mining projects could accidentally put one on a dangerous trajectory. Key notion though is that we can’t assume luck will protect us because even ignoring that asteroids hit us from time to time naturally, a civilization moving into space opens up many new avenues for increased space debris and collision dangers we will need to defend from. The first key to defense of course is knowing where the threat is. Early detection is key to asteroid defense, because their sheer speed makes it easy to miss them until it is too late to redirect them. In general an asteroid impact crater will be ten times as wide as the asteroid that caused it because of the enormous kinetic energy released by the collision. Asteroids vary in speed of impact but usually move in the tens of kilometers per second range, and would cover the distance from the Moon to the Earth in under a day. Timelines for such an object being spotted at interplanetary distances and reaching us might be around a year but we need to see it clearly enough to know its trajectory, though we currently still haven’t spotted most asteroids in the Belt that are considerably larger than a kilometer across. Anything over a kilometer across represents a major threat to us, likely to leave millions dead and trillions of dollars lost, and it would be very hard for us to spot nowadays. Such an object a kilometer wide would be three million times dimmer than the moon at the same distance from us as the moon is. That would be about 16 dimmer in terms of apparent magnitude than the moon, which is a -13 at a full moon. For astronomical magnitude every 5 is equal to a factor of 100 in brightness, and that would make it about a 3 so it would be noticeably visible to the naked eye but hardly bright, plenty of nighttime stars are 3’s. An object’s apparent brightness drops off with the square of distance, so one a ten times further away will be ten-squared or one hundred times dimmer, or 5 orders of astronomical magnitude dimmer, so that same asteroid we mentioned a moment ago that was decently naked-eye visible out at the moon’s distance would be an 8 at that point, ten times further away, and visible with binoculars. The asteroid belt is around thousand times farther from us than the moon and so is a million times dimmer or 15 orders of magnitude dimmer, but it’s actually worse than that because we see them by reflected light from the Sun which also falls off with the square of distance, and the Belt is much farther from the Sun than Earth is. Space is big and these things are dim and one headed toward Earth is not going to stand out much until it is too close and we have little time to react. Now we could build much bigger telescopes in space and more of them, see our Megatelescopes episode, but this relies on passive detection and these asteroids have their light all scattered around the solar spectrum like most objects reflecting light. It is much easier to pick up an object shining dimly but in a specific narrow frequency than one shining brightly in a white spectrum, and this is the basic notion of ‘active’ detection. You blast out a rapid pulse of some tight frequency of light, usually radio or microwave rather than visible, and that tends to reflect off the sort of substance you are looking for, and see what scatters back and with the time of return and direction you’ve got your ping – that is essentially RADAR. You can also do very wide images shot from multiple angles and have a computer come back and crunch the numbers for matchups, which is an approach you could use with ambient light like solar illumination or the infrared blackbody radiation given off by the object. Indeed for the latter the peak wavelength of infrared will also give a fairly good idea how far away it is from the Sun, as that correlates to temperature of the object. Both of these approaches benefit hugely from having lots of detection gear in space and not just in orbit around Earth. You could also put them at Earth’s Lagrange points or any number of other orbits to give yourself a much better resolution and detection capacity. You need to do this as you go out in space too because our atmosphere protects us from small junk, which is vastly more common than big objects, and things in space do not get that protection and can be trashed by a fist-sized one-kilogram meteor that would have been torched by our atmosphere. Indeed about 25 million hit Earth every year, nearly once a second, to the tune of about 15 million kilograms a year. And keep in mind there’s nothing special in this regard about Earth. Our gravity well does make us get hit a bit more often than some random bit of empty space of the same volume, but not that much. Space is full of dangerous stuff, and will be more so as we start littering the place with our own junk. So you have a very good motivation to put up that detection and monitoring system if you want to build a robust presence in space, and that presence makes it much easier to build that detection system. Monitoring is important too because keeping track of all these objects helps avoid them--not to mention that if you check in and see that one isn’t where it is supposed to be that means something struck it or perturbed it, which would cause lots of other stuff to be flying around on potential new collision courses, and it’s easier to find those if you can calculate from where they got nudged or blasted loose. A future humanity in space needs detection and monitoring and can do it easier in many respects than we can now, but what about now? What would we do if we picked one up? There is a persistent myth that nuking asteroids would not be effective. But the First Rule of Life In General is, “If brute force isn’t working, you’re not using enough.†Yes, you could turn an asteroid into sand and golf balls by hitting with enough nukes, though a really big asteroid would require several times more nukes than currently exist on Earth. And if blasting it apart were your only strategy, you would have to blast it into pieces that small to be sure the atmosphere could burn them up, because if the Earth were going to be struck by the Rock of Gibraltar, peppering it instead with a billion hurtling Volkswagens would actually be worse. This approach to asteroid management would also leave you having to track and avoid all the shrapnel you created. A far more efficient and tidier way to use nukes against asteroids is to detect an asteroid's collision course with Earth early, very early, and nudge it onto a slightly different path. The high energy radiation from a nuke will vaporize or ionize a very thin layer of one side of the asteroid, trillions of tiny explosions pushing on the asteroid like rockets. If we approximate the asteroid as a sphere, the optimal detonation placement to yield the greatest nudge per nuke is actually about an asteroid radius away from the surface. Distributing the pressure over so much of the surface greatly increases the chances that the asteroid will stay in big pieces, which are easier to track and avoid later, after they miss Earth. And the nudge you need isn’t very much, relatively speaking, if your network detects at a distance and defends quickly. Traveling 1 m/s for 70 days, you’ll cover a distance equal to the Earth’s radius, which means that if you can change the velocity of an incoming object by just 1m/s 70 days before it hits Earth, you’ll have saved the Earth--even if in a somewhat uncinematic way. The real issue with using nukes, at least at the moment is that warheads are not terribly fast, sturdy, or lightweight items except in terms of how much punch they pack. You cannot just load a hundred megaton nuclear warheads onto a shuttle or rocket and fly them into space. They are also somewhat delicate items, in that the detonation trigger is a high-precision device, the design of which challenged the world-class engineers and scientists on the Manhattan Project. It’s even more difficult to design and build one that will survive the shaking of a high-g launch into space and still function reliably when it reaches its target. Contrary to what movies show, blowing up a nuke will not set it off, it will only break it and make it non-functional. So you can’t send a barrage of simultaneous nukes at a target unless you are incredibly precise about the timing, otherwise the radiation blast or tons of high-velocity debris from the first nuke will disable the others. But just getting your nuke up even to high orbit is no small trick either. Warheads aren’t light but ICBMS are down right heavy, what with all that rocket fuel, and are not designed to be launched from orbit. Trying to rapidly retool and refuel ICBMS to be carried into orbit on a rocket then launched from there so they could reach something out in high orbit or the moon is not a quick or easy thing to do. There is a reason we use phrases like ‘this isn’t rocket science’ and ‘this isn’t brain surgery’, and rapidly retooling an ICBM and an orbital launch rocket to a job neither was meant for, or ‘rocket surgery’ is considerably harder. So if we want to nuke an asteroid we need to build those nukes from the get-go with that in mind and we should be putting them up in space, so we aren’t needing to deal with orbital launch energy costs or weather windows scrubbing that launch. This kind of precaution carries the small problem that some folks are squeamish about having atomic bombs whizzing around in orbit overhead - and that both warheads and rockets need lots of constant maintenance to work which is hard in space. The other problem is you have to fly the rocket there and they do have rather long flight times. Again early detection is the key since it gives you more time to get your bomb ready for the flight and actually fly it there. Some asteroids are just a big ball of gravel loosely held together by gravity while others are more of slab you can shatter, and we call the Impact Disruption Energy the kinetic energy needed to shatter an asteroid and remove at least half its mass if we just whack it with another object… like if we shoved another smaller asteroid or space station or spaceship in its way that it plowed into. Part of this energy is the shattering energy, and is generally proportional to the mass of the asteroid, but you also have the gravitational energy in there, because it does have gravity and if you shatter it the bits can just fall back down and reform, so you need to shatter and blow it apart. In general for smaller rocks that shattering energy is much higher than the gravitational energy, larger ones though are gravity-dominated. What we’re seeing here is that while yes, nukes can absolutely get the job done, again with sufficient brute force you can get almost any job done, they are not ideal. Especially now. Down the road and with far better detection, an Earth-bound asteroid wouldn’t be such a world-shaking calamity. After all it is a bunch of free metal already headed your way you can mine and harvest on the cheap. High-tech civilizations might just regard an incoming asteroid as free stuff. But that is a good way off, so how about more short term? If not nukes, what is the alternative? One innovative suggestion was to fly a ship out to spray paint the asteroid to be highly reflective, so that reflecting sunlight will push it like a solar sail off course, but this probably isn’t practical with anything but smaller ones and very early detection. However, it’s not a bad approach if you can add more light pressure with a laser, and we have often discussed using lasers to push spaceships up to high speeds, as we looked in Interstellar Laser Highways. You could also maneuver that asteroid around to some place you wanted it, like into a lagrange point to serve as a nice base for a space station. Of course, if you have lasers that powerful and if time were limited, you could skip the reflective paint job and just hit the asteroid with the laser directly. This will produce significantly less thrust, but it will at least produce the same surface-vaporization rocket effect as the radiation from a nuke, but in a slower, more controlled version that’s less likely to messily shatter the asteroid. The big benefit is that light is near-instant, even over the vast tracts of interplanetary space it gets to its target in minutes not days or weeks. You can also keep at it, it’s not a single expenditure of energy like a bomb. Nukes might seem like they have a lot of energy in them – and they do as atomic energy is far denser than chemical energy, but a megaton H-bomb still only has the energy equivalent to what the United States power consumption is over a couple of hours, so if you plugged that into a laser and kept it on the asteroid it would be delivering a dozen megatons of zap to that asteroid every day and delivering it precisely in mere minutes from when you flipped it on. Remember, you’re not trying to simply zap the thing and blow it apart, rather you’re cooking or ablating off its surface with a more diffuse beam to act as propellant to shove it aside. You basically are shining a powerful flashlight on it to push it aside using its own heated matter as the propellant. We’ve discussed parallel tricks to this for snatching comets in from deep space to help provide water for terraforming and artificial space habitats. Your laser provides the energy and the struck object provides the propellant that energy superheats. Now I like this method for a couple of reasons. First, you can’t exactly plug the planet’s power grid into a big laser, our atmosphere is kind of in the way, but space is a great place for renewable energy, namely solar panels that never have to worry about clouds or nighttime, and we talked before in our power satellites episode about how handy it is to get power this way and beam it down as microwaves to Earth, as diffuse Masers, the microwave variety of laser. Indeed, it is on my shortlist of things likely to kickoff major space industry as our energy sector is a multi-trillion dollar one so moving it to space gives us huge resources for other space projects to piggyback on. But you could easily divert part of this power supply to such lasers to occasionally vaporize more mundane space debris or push ships away from Earth to our various colonies. Lasers are also easier to secure against theft and misuse than nukes lingering in orbit or on the moon. So that would be my preferred approach to asteroid defense, but we have many and what they all rely on ultimately is early detection and a robust presence in space, which also gets all your eggs out of one basket in case another Moon-maker or dino-killer heads our way. Ultimately, your best defense against asteroids is not an individual system like nukes or lasers but simply that robust push for space development. The best way to protect ourselves from threats from space is to expand ever outward into space. We’ll be talking more about the uses of asteroids in the coming months as we continue our new series, Becoming an Interplanetary Species, and we just had our second episode of that come out this week, looking at colonizing Cislunar Space. For those of you who are subscribed to Nebula, our new streaming service, you already had a chance to catch today’s episode as an early release, and while I’ve enjoyed putting our mid-month bonus episodes up there a couple months early, I have decided for now to switch away from doing that in favor of just releasing ALL our future episodes on Nebula a couple days early, and ad free. If you’d like to catch all of SFIAs episodes early and without ads, or see any of the great content from our sister channels on Nebula, you can signup for Nebula today, or you can get it for free by instead signing up for Curiosity Stream, whose partnering with us to bring you the best education videos out there. Curiosity Stream has excellent educational content of their own and they are running 26% discount if you use the link in the description. That’s a great deal since it means you get a year of both Curiositystream and Nebula for less than $15, and it helps support this show and a lot of other educational content which is what Curiositystream and Nebula are all about, and again you can get a year of both for less than $15 by using the link in the episode’s description. So as mentioned we are continuing our look at Becoming an Interplanetary Species, and we’ll start October off with episode 3, as we look at returning to the Moon and staying there. But there’s more to come before then, and this Thursday we’ll be taking a look at the Future of Fission, as we celebrate the sixth anniversary of the show. Then the week after that we’ll be back to the Fermi Paradox series to look at the Phosphorus Scarcity problem with life evolving, then close the month out with our Livestream Q&A on Sunday, September 27th, 4 pm Eastern Time. If you want alerts when those and other episodes come out, make sure to subscribe to the channel, and if you’d like to help support future episodes, you can donate to us on Patreon, or our website, IsaacArthur.net, which are linked in the episode description below, along with all of our various social media forums where you can get updates and chat with others about the concepts in the episodes and many other futuristic ideas. Until next time, thanks for watching, and have a great week! This video is sponsored by CuriosityStream. Get access to my streaming video service, Nebula, when you sign up for CuriosityStream using the link in the description. When we say our future in the solar system is to Become an Interplanetary Species, folks tend to think of a handful of planets, but as we’ll see today, our destiny awaits us on a million smaller worlds too. So today we are continuing our look at becoming an interplanetary species. This is Part 5 of our series loosely following the National Space Society’s Roadmap to Space Settlement as our guide, and I’ve linked the complete document in the episode Description. Last time we looked at establishing our first colony on another planet, Mars, and today we’ll cover the roadmap’s Milestones 26, 27, and 28 settling asteroids and moons, as well as orbital habitats of our own creation. Now back in part 2 we looked at colonizing the orbital volume around Earth, and we talked about the importance of the Moon as a source of raw materials. An important point we made there was that because of the Moon’s lower gravity, only a sixth of Earth’s, and the fuel cost of lifting materials out of a gravity well, it’s actually much cheaper to move raw materials from the Moon’s surface to construction yards in Low Earth Orbit than it would be to lift them up from Earth’s surface only a few hundred kilometers below. However, even though the Asteroid Belt is even farther away, hundreds of millions of kilometers, in many cases it will be even easier to bring resources to Earth from there than from the Moon. More to the point, it is a great place to get resources for other efforts in the solar system. So too, our Moon is but one of many in the solar system and all of them are easier to get resources off of than their planets. So we will be looking at how to do this, why we want to do this, and how a basic solar economy will develop from it to fuel colonization of this solar system, and to set the stage for reaching and colonizing the next. Milestone 26 is the Robotic Characterization of Asteroids, particularly the Near Earth Asteroids, those whose orbits make them the cheapest to bring materials back from. These asteroids happen to also be the ones that are the greatest potential threats to us. Telescopes and radar arrays in Earth orbit will be able to tell us a lot about asteroids, but probes like NASA’s Osiris Rex probe, will let us take direct samples and place beacons on these objects to make it easier to track and monitor them, and see which ones have which resources we want. In the long term we will want them all, and there are millions of asteroids in our solar system. Each one may represent billions or even trillions of dollars of valuable resources, so the ability to catalogue these with cheap robot probes will be invaluable and one of the earliest manufactured goods we might expect to be built in space for use in space is likely to be those probes. This will be a continuing project of course, but early on we want to focus on those near-earth asteroids and on finding any with metal concentrations. Some of them may be easier and cheaper to get metal off of than the Moon, and for that matter, while we often picture our orbital habitats as big spinning cylinders, this is likely to only be the internal view. Wrapping those cylinders in a shell of cheap material, like rock from these asteroids, represents a great shield against meteor damage and to minimize leakage of air. Milestone 27, the Utilization of Asteroids, is therefore not just about mining them for gold or other precious metals, but also their use in Milestone 28, construction of orbital space Settlements and other space habitats, where they will provide not only the metal for the structural elements, but also the bulk exterior shielding and the interior landscaping, all the dirt, air, and water we’ll need. And though we call the parts of this roadmap milestones, they will all be ongoing overlapping processes we’d expect to see under constant upgrade and expansion. In the early days of asteroid mining the focus is entirely on finding the asteroids with the least delta-v relative to Earth, then finding the ones with gold and platinum on them, but eventually becomes about finding the very tiny ones because you want every drop of raw materials in those asteroids and every one of the smaller ones represents something of a navigational hazard. In a similar vein, early orbital settlements will be about what is cheap – but then again, so will later orbital settlements, what changes is what is cheap, and as you get that asteroid utilization going, resource scarcities shift. Sometimes it is suggested we might bring an asteroid back to Earth to place it in orbit. Now this is sometimes viewed as a bad idea because it might land on us, but that’s not really a concern. You would need to be careful to have redundancies and security on board when pushing the asteroid in, but you don’t exactly accidentally hit a planet so that’s a safeguard against intentional sabotage. Once it’s in orbit it's less of a concern. There’s two reasons why you wouldn’t bring whole asteroids to Earth orbit, and the first is that asteroids are often just big balls of loose gravel, a great recipe for adding more dangerous space debris to Earth’s orbit. That’s easily rectified though by covering the asteroid in some shell of plastic or foil. The other bigger reason is the sheer amount of mass. If an asteroid is found to have a gold or platinum abundance of 1 part per thousand, then we only want to ship home that one part per thousand, not blow a thousand times more fuel bringing the whole thing home. Now as time goes by you’re interested in more and more of the materials in those asteroids, though often for local use as we colonize the Asteroid Belt. However, while we mostly don’t want to move asteroids, early on there is some motivation to bring small asteroids right back to Earth orbit, as ones a few hundred meters across might be nudged from their Near-Earth orbits into stable orbits in Cislunar space and converted into orbital settlements with a lot of mass and shielding available. This was often contemplated by the L5 Society, the precursor organisation to the National Space Society, as a way of sourcing the mass for large Lagrange Point Orbital Settlements. Alternatively, last time in the series we were discussing Aldrin Cycler Castles between Earth and Mars, essentially large space stations on elliptical orbits that take them by both planets, and a lot of Near-Earth asteroids might be ideal for conversion into cyclers between Earth and other destinations in the solar system. As we mentioned earlier in the series, we would always anticipate the majority of space habitats as Earth orbital settlements until such time as Cislunar space was truly crowded to capacity, but let us ask what other places we might have them? A big factor in that of course is how well humans can handle lower gravity. If the answer is that even Mars has too low of a gravity for humans to comfortably live in, then humanity’s future in space will be principally in spin-gravity stations from the outset. If we can handle lower gravity like our Moon and the other large Moons of our solar system have, then we are likely to grow initially on those places and only begin heavy construction of spin-gravity stations like the O’Neill Cylinder when we have more people than Earth and all those other places could handle even if they were all converted in to Ecumenopolises – Planet Wide Cities – or in this case, Moon-wide cities. Even then we would expect lots of these stations around Earth, in the Asteroid Belt, and probably as the Cycler Castles too. While Cyclers on their long elliptical orbits are hardly fast means of transport, they are ultra-low energy approaches to it, and big space stations serving in this role, complete with heavy shielding and life support options like hydroponics and gardens, are likely to become heavily used in the middle days of solar settlement. An Asteroid you’ve hollowed out and shoved onto a cycler trajectory between two large bodies of interest is potentially an ideal approach for this. When we say we want to hollow one out, we generally mean more like expanding it like a balloon. A rocky asteroid with a diameter of 100 meters and a density of about 2 tons per cubic meter is going to mass about a megaton, or 10 Aircraft carriers, and if you ground it up and made a hollow sphere out of the rock half a meter thick, your 100 meter wide asteroid is now a hollow spherical shell 560 meters wide instead, encompassing around 90 million cubic meters, 100,000 times what our space station’s volume is, and which has nothing like a half-meter of metal or rock as a protective skin against impact and leakage. There are several thousand asteroids in this size category that qualify as Near-Earth Objects alone, there are many millions of asteroids that size in the actual asteroid belt. And I want to emphasize that difference real quick as when we’re talking about asteroid mining and asteroid utilization, the emphasis is mostly on the relative handful of them that are Near-Earth, which is again many thousands, not the Millions in the main Asteroid Belt. That all comes later. I would not be too surprised if virtually every Near-Earth Asteroid saw itself converted into a Cislunar Orbital Settlement or a Cycler Castle. They represent a minimal danger to Earth if brought into orbit, as an asteroid of this more modest size on a known and decently stable orbit is easily exploded without even resorting to atomic weapons. However they would be a heck of hazard to other things in orbit if you did that. So assume any asteroid brought back to Earth to serve as an orbital settlement would at least be having a coating of foil or ice or similar applied to minimize them kicking out debris from minor impacts. Many asteroids are basically just big balls of gravel loosely stuck together and same as you don’t want to be right behind a car driving down a dirt or gravel road spraying you with everything they kicked up, you don’t want any objects in orbit of Earth that are producing any more space debris than can be avoided. What about actually colonizing the Asteroid Belt? Well first we have to ask which belt we mean. The Asteroid Belt between Mars and Jupiter is actually multiple hazy belts, loosely defined as the Inner, Middle, and Outer Belt. We also have the Jovian Trojan Moons and the vastly larger Kuiper Belt out Beyond Neptune. On top of all that, same as Earth has thousands of near Earth Asteroids that aren’t part of the Belt, there are many thousands of large rocks in our solar system that don’t fall into the normal collection of Belts, Trojans, Moons, or Rings. This is a big part of Space Settlement and becoming an Interplanetary Species, because it’s realizing that there are not 8 planets in our solar system, nor even a few dozen when we throw in Dwarf Planets like Pluto or Ceres or the Larger Moons like ours or Titan and Ganymede. It’s realizing that there are millions of minor planets in this solar system. Colonizing these is what’s going to turn us into an Interplanetary Species, not setting up a handful of dome habitats on Mars or floating cities on Venus. Of those millions of minor planets, each one has the potential to be turned into a space habitat the size of the Kaplana One space settlement, and around perhaps a million into full blown O’Neil Cylinders home to a million people each. That’s without even tapping into the Dwarf Planets or Larger Moons, each one of which has more raw material than all the asteroids combined. This, then, is our true future as an Interplanetary species, because those millions of minor planets aren’t that minor, and what might begin as a small outpost for asteroid miners on most will likely transform over time into millions of city states. Each one will develop uniquely, but let’s consider a few scenarios. We contemplated the future of the biggest asteroid, Ceres, in our episode Colonizing Ceres, and how it might become a trade hub and agricultural center for the Asteroid belt. Let’s look at another case, imagine a gold rich and larger asteroid, such as we believe 16 Psyche to be. It’s roughly 16th place in terms of size in the asteroid belt, and is an M-Type asteroid, meaning metallic, that we think may have been the remnant exposed iron core of a protoplanet. Our early solar system was a very different place with many more mid-sized planets, some merging together, others being gravitationally ejected from the solar system or swallowed by the Sun, and many remaining as moons or failed planets like Psyche. It’s also one of our earliest finds, being discovered in 1851, just a few years after Neptune and long before Pluto. It’s symbol is meant to be a butterfly wing and a star, as Psyche was the Greek Goddess of the Soul and that was typically represented by the butterfly’s wing. Back then we were still giving each new asteroid discovered its own symbol like all the planets had, in part because we were still calling these asteroids planets, all of them being larger examples of their type. We didn’t even know there was an asteroid belt yet, but we started discovering a ton more of them about this time and were running out of symbols, so astronomer J.F. Encke suggested we just use a circle with a number in it, in this case a 16, and within a decade we discovered around 100 more asteroids and any thought of naming each went out the window. Psyche is of interest because of its exposed metal, and we’ve been talking about missions there for some years now. Many of you might remember articles in recent years talking about an asteroid having trillions or quadrillions of dollars in gold in it and those were generally referring to Psyche. Early in 2020 NASA awarded SpaceX a hundred-million-dollar contract to launch a satellite to orbit and probe Psyche, and the current launch date is planned for 2022, with a Martian gravity assist to arrive in 2026. It seems probable that the first exploration of almost all bodies will be done by robots, so I’ve often wondered if folks living on those bodies in the future will commemorate that as a holiday. It would seem like the big 3 most would have would be the day the body was discovered by telescope, the day it got its first orbital probe or rover, and the day a human first stepped on it. Of course, resource harvesting might be entirely automated, especially on smaller rocks where we might just envelope them in a Mylar bag and cook the materials out, but Psyche is a good deal bigger and basically is the Queen of Metallic asteroids. With a surface gravity of just 1.5% of Earth-normal – which is quite high for an asteroid, there’s still a recognizable up and down, and with an escape velocity of 180 meters per second or 400 miles per hour, you don’t have to worry about accidentally kicking yourself into space from its surface or random mining debris drifting away, so you don’t need to bag or dome the spots you’re working on. We believe its surface to be composed of about 90% metal and 10% silicate rock, and most of that metal is iron and nickel, same as our own planetary core. That’s great building material for space settlements, but the real initial interest is in precious metals. Earth has a lot of precious metals, but most of them are sunk in our planetary core which is why Psyche, suspected of being an exposed core of an early protoplanet, is of particular interest. That iron though is over a million times what we produce a year, and in the long term is probably its greatest value. In the short term, “there’s gold in them there hillsâ€, and platinum and so on, and we estimate the total amount of metals in it, sold at modern value would be several hundred quintillion dollars, more than a million times our annual planetary economy. You don’t mine that all at once, and again it’s the size of a medium-sized nation or state so you don’t tow that home either. You set up on it and slow extract raw materials at the rate the market desires. You’ll be producing a lot of other metals as you’re extracting the precious metals, and those you’ll use locally or ship off to wherever the market is willing to pay the bill for shipping them. As you’d most likely be producing large numbers of tunnels, which are very easily shored up when gravity is 1.5% Earth normal, you can start building habitats inside those tunnels much like the lavatube colonization we often contemplate for the Moon. At roughly thrice the distance from the Sun Earth is, it still gets enough sunlight that domes on the surface, or with light reflected down via mirrors, could profitably grow food. You would never have decent gravity on the place, though we’ll discuss some options in the next episode for dealing with that like using artificial black holes, so if folks want to live there they would need to use spin-gravity habitats buried in those tunnels, and we discussed that more in Colonizing Ceres too. Alternatively, you might build orbital settlements around it, using all that iron and some of that silicate for making them. We don’t normally think of building space stations in orbit of asteroids, since they already have such low gravity and no atmosphere it seems a bit pointless, in favor of embedding them down into the asteroid where they’d be protected from meteors, however this might not be too uncommon. Landing on a planet or taking off from one is always a bit of a pain, and a space station orbiting one would have only a very small delta-v. Indeed many smaller asteroids are spinning nearly as fast as their gravity can hold material on the ground so your equatorial orbital speed, relative to the ground, won’t be terribly high. Psyche is big enough we might consider building it with a mass driver track of its own, but it’s also low enough gravity you could erect monstrously tall space towers on it too. That’s a potentially interesting scenario because inside the asteroid belt there are so many smaller asteroids whose delta-v to each other or Psyche would be small enough we might just give them a shove into orbit of Psyche, if it had developed enough to have sophisticated refining and manufacturing going on. So come for the gold, stay for the industrial titan the place is likely to become! And indeed, it might get fairly common to lasso smaller asteroids into orbit around the bigger ones and flat out tether them to each other for easy transport. That’s ready made to eventually end up as a rather large nation-state of many millions or even billions. Psyche alone has enough mass to forge a million full-sized O’Neill Cylinders. I suspect that will be the path for a lot of asteroids though, especially the more modestly sized ones only a few kilometers across. A robot probe finds some nice deposits of valuable metals, folks go down and mine it for a few decades, and as the wealth pours in they expand their facilities and form a community. Even after valuable metals are exhausted, the remaining materials would be valuable to that settlement which is capable of mostly self-sustained growth at that point, and they diversify production to engage in trade with neighbors... and with Earth, which will be growing a massive cloud of orbital settlements by now. Let’s consider one other pathway for asteroid utilization. Many of those near-Earth asteroids are only near occasionally. They have wide elliptical orbits that take them near us occasionally and have lower delta-v to reach than most Belt Objects. Many of these are ideal for early asteroid mining and we are likely to send that material back to Earth Orbit by some means like an electromagnetic catapult, solar or nuclear powered. When you’re hurling mass from something in space, you move that object too, and careful timing could let you nudge that asteroid over time into a Cycler Orbit between Earth and some spots in the Asteroid Belt, or other planets and points of interest. Having gotten materials out of them, and gotten them fairly settled, we could convert them into mobile waypoints as Cycler Castles, and this might become a preferred means of cheap travel as they’d essentially be Cycler Castles of the Space Habitat scale. Back at Earth, whose orbit is swelling with orbital settlements fueled by all this solar system resource extraction, we might begin seeing thousands or even millions of cycler castles of various sizes and pathways emerging as having Earth at one end of that cycle. And if you saw our recent episode on Interstellar Trade, where we discussed interstellar cyclers, we could employ some of those same methods to make for fast moving cyclers and space highways. Indeed you might set up laser pushing stations on dozens or hundreds of massive cycler castles on the same path to serve as the relay chain for fast moving spaceships pushed along by them. This is the true path of interplanetary colonization though. Orbital space around earth growing heavy with installations in a giant cloud, even as the larger moons, asteroids, and planets become slow-growing replicas of that Earth cloud, and the Asteroid Belts and other minor planet swarms grew from mines to hollowed out giant habitats by the million. This might be accompanied with vast thin but enormous solar collectors closer into the Sun beaming energy out to places that needed it. This is Interplanetary Humanity, scattered across a million worlds without yet having ventured out of the solar system, not our usual image of a handful of terraformed planets and moons. That may happen too though, especially as practice for colonizing other solar systems, and we’ll explore Terraforming, Para-Terraforming, and our steps out into the galaxy beyond next time. For now though just remember this, we do not need to colonize the galaxy to colonize a million worlds, we just have to colonize our backyard, this solar system is an immense place with immense resources, able to take us forward into being a civilization who scope and scale rivals any of the galactic empires we see in fiction. So today we saw how asteroid mining would help shape interplanetary settlement and trade, and last week we were talking about interstellar trade, but we also looked at trade with alien civilization in our Coexistence with Alien series, exclusively available over on our Streaming Service, Nebula. We also show all our new episodes there a couple days early and without ads. If you’d like to catch SFIA episodes early and without ads, and help support the show while you’re doing it, you can sign up for Nebula today, and see that Exclusive Coexistence with Alien Series along with other great content from our sibling shows. However, we also have a deal running with Curiositystream, where if you sign up for them at the link in the episode description, you not only get a 26% discount, but free access to Nebula while you’re a Curiositystream subscriber. Curiosity Stream has excellent educational content of their own and they are running a 26% discount if you use the link in the description. That’s a great deal since it means you get a year of both Curiositystream and Nebula for less than $15, and it helps support this show and a lot of other educational content which is what Curiositystream and Nebula are all about, and again you can get a year of both for less than $15 by using the link in the episode’s description. We’ve been discussing colonizing space, huge colonies on asteroids, moons, and planets, and our destiny as an Interplanetary species, but mostly we haven’t looked at the life of the individual involved in colonizing space, so next week we’ll be taking a look at Life as a Space Colonist. That’s a future we might live to see, and certainly the next century promises to be quite interesting, with many challenges too, and in two weeks we’ll ask what it will take to Survive the Next Century so we can see that bright new future on other worlds. Then we close November out with our monthly livestream Q&A. If you want alerts when those and other episodes come out, make sure to subscribe to the channel, and if you’d like to help support future episodes, you can donate to us on Patreon, or our website, IsaacArthur.net, which are linked in the episode description below, along with all of our various social media forums where you can get updates and chat with others about the concepts in the episodes and many other futuristic ideas. Until next time, thanks for watching, and have a great week! Our topic for today is Asteroids, not just mining them but the vital role they could play in spreading ourselves out around the solar system. Now chances are you have already heard or read about the idea of mining asteroids. I have noticed that there is a lot of talk about the idea but as is often the case not much beyond surface detail. One is left with an impression that asteroids are rocks in space with metal in them, presumably some of it quite valuable like platinum or gold, and that we would like to have those precious metals brought home to Earth. So far so good. But while platinum and gold are quite valuable, and useful too, not only does much of that value come from scarcity, which means hauling back megatons of the stuff would not be nearly as profitable as it sounds like, but it occasionally occurs to people that Earth, out-massing every asteroid in the solar system combined, actually has considerably more of these metals than they do. Indeed before we finish today we will pretty much kill the fictional notion that anyone will be exporting iron or other bulky metals back to Earth, even while we see how incredibly useful mining these things will be. And to do that we might as well begin with what an asteroid is, because it often misunderstood and vague. Asteroid is a loose term, and not a great one either since it means star-like, which they certainly are not. The first one we discovered, back in 1801, Ceres, is generally not even considered an asteroid anymore, but a dwarf planet like Pluto, making it Dwarf Planet #1 or planet #5, between Mars and Jupiter, depending on how you view Pluto. It’s about 4 times more massive than the next most massive asteroid, Vesta, and masses about half of what the rest of the asteroid belt combined masses, which number tens of millions of objects, many thousands of which could do double duty as mountains or kill off the dinosaurs. So Ceres, and the other famous asteroids, are not particularly representative of what we mean we talk about asteroids. And when it comes to mining them, it’s actually the small ones that interest us more than the big ones. And it’s not just about size. Asteroid composition is anything but monolithic, as it were, but loosely falls into 3 categories, C, M, and S type. Those are easy to remember since they are short for carbon, metal, and silicate, or stony. C-type, carbon rich asteroids, are the most common, making up 75% of asteroids, while S-type, silicate or stony asteroids, comes in a distant second at 17% , M-type Metallic asteroids are much less numerous. Now when it comes to mining that hardly tells the whole story, M-types are mostly nickel and iron, neither of which we’d particularly want to bring home to Earth, but which would be valuable for building stuff in space. For that matter there are also several sub-types of asteroids and two different classifications systems, and the asteroid belt is anything but the only place you can find asteroids nor the nearest place to find them. It also is not unusual for two asteroids of different types to blunder into each other and merge or to be somewhere in between these types. C-types, the most common asteroid and also the ones that gets ignored a lot in asteroid mining conversations focused on impressing folks with the idea of mountains of gold, are quite valuable themselves. They contain lots of water, which is never a bad thing to find in outer space. But they also contain plenty of life-useful elements and particularly noteworthy is phosphorus. Something that is quite hard to find on Earth in concentration and a major bottleneck on agriculture, so if asteroid mining ever gets heavily developed and cheap, that is the sort of thing we might bring home since it is valuable. Not as valuable as gold or platinum of course, nowhere near, and these big space boulders have a lot of those. We’d estimate that the usual S-type asteroid, not even the less common metallic m-types, are full of tons of metals, many valuable. One as big as your house would be expected to contain hundreds of tons of metal, and about your weight in gold and other precious metals. It is worth remembering that back when Earth formed as a big ball of molten rock most of the metals sank to the core. This did not happen with these small asteroid of course, and wouldn’t matter if it did since most asteroids are not big and are incredibly easy to mine, at least if you ignore them being millions of miles away in the radiation blasted airless void of space. Which I think we would have to classify as a bit of an inconvenience. Still your average asteroid is a loosely held together ball of gravel and even the big ones have such low gravity you could bench press a truck on them. Generally speaking those house-sized asteroids have such low gravity that if two of them were touching you could squeeze in between them and shove them apart. Of course the odds of two touching, or even near each other, is quite small. Even in the asteroid belt which is quite dense with them, the distance between any two asteroids is large. Unlike fictional representations where asteroids are shown maybe a few hundred feet apart, the ones in the belt tend to be a few hundred miles apart, and a lot more if we’re only considering asteroids bigger than a mile across. There may be around half a million of them but the belt is so large that the spacing would be more like a million miles between them. If we’re talking smaller objects, that amount would drop a lot, but we wouldn’t be mining small boulders. You don’t need to ram into something the size of a house though, honestly even a fist sized chunk of rock can mess up your whole day if you blunder into it at thousands of miles per hour, but there is not much reason to go that fast when meandering around the belt to visit the nearest other big asteroid. So asteroid miners in a well developed belt, should it become a major industry, carrying ore from wherever they have been prospecting back to some central base, might just cruise around at subsonic speeds where anything they cannot see and dodge would just bounce off a well-armored hull. We tend to think of all collisions in space as fatal and radiation as dangerous but that is mostly because our modern ships are built tissue paper thin to save mass or we are thinking of the ships as plowing around full speed ahead, but in many cases a ship would be better off saving fuel at a nice slow pace and going for thick armor. Potentially temporary armor just made of its freight, you might strap your mineral wealth to your outside so it takes the collisions instead. You could glue cargo to your ship with ice for instance. If we saw a big buildup of Belt Mining operations you’d be likely to see spheres of operation near some decently large C-type asteroid where food and fuel could be made and without gravity playing much of a role large ships could burn around that region quite easily. Indeed once you are up in space, ships do not require much sophistication. An airtight metal can with some simple chemical rockets, or even pressurized gas, would get the job done. You do not need much delta-v, or fuel as a result, to cover a few thousand miles of empty space. A lot less than you would need to drive that distance on Earth, and you’d make the trip in less time. No gravity slowing you down, no air friction or drag doing the same. Of course the Asteroid belt is also not the only place that has asteroids, and most planets including our own have collections of them meandering about tagging along our orbital path. These are called Near-Earth Asteroids, and we’ve identified thousands of them ranging from man-sized to 20 miles across. Now we also have a sub-type of near-Earth asteroid called EROs, or easily recoverable objects, ones that would take very little fuel to bring home. Or to bring bits of home. Which is probably worth addressing. I have often heard it suggested we might tow asteroids back to Earth orbit… I have no idea why we would do that. We’ve got plenty of rock down here on Earth and plenty more on the moon and way too much junk kicking around in orbit already without adding more. Why send home a megaton asteroid, the super-majority of which has no value down here, when you can extract what you want there and just send that home, saving a lot of fuel? You might also wonder if the cost of fuel, which is very expensive, eliminates asteroids as a good candidate for mineral extraction. And the answer is no, for one thing it takes weigh less fuel to move a ton of matter from an asteroid to Earth then a ton of Earth to an asteroid. A ton of gold, in a literal sense, is worth about 40 million dollars, and is about the size of a basketball. A million bucks in gold weighs about 50 pounds. I always find it amusing when a chest of gold is described in fiction brimming with coins and big enough you could probably squeeze a person into one. You’d need a forklift to budge such a thing. And yes, even as expensive as getting a ton of matter into space is, it is still significantly less than value of gold and again it’s a lot cheaper to bring the stuff home. If your mining operation were running you, say, 20 million bucks a ton to get to the asteroid and you needed a hundred tons of crew and equipment, that’s a two billion dollar operation on the fuel side, call it double that, 4 billion for the lesser amount of return fuel and all the equipment itself. You’d need to dig out an equal mass, about a hundred tons, to break even. But what’s actually entailed in such an operation? Let’s say we wanted to setup shop on one about a mile across. We’d expect several thousand tons of precious metals in an S or M type asteroid of this scale, maybe a hundred thousand tons total, hypothetically several trillion bucks worth of precious metals. Of course you wouldn’t want to bring that all home at once, even if you could, that’s how you crash markets. But something like that would need to be a long term operation. So more like a permanent base. The first few trips might be to small ones you could bring home and maybe dissect in low orbit, but eventually you would want to settle in for some serious mining. But also some serious construction too. And some serious manpower. We need to keep in mind that Near Earth asteroid doesn’t mean it is actually near-Earth, just that it occasionally passes near us. So belt or near-Earth, it does not behoove potential mining companies to go dragging these things back to Earth. Just the refined metal, and even then mostly just the precious ones. That does not make the other metals useless though, quite to the contrary, in many cases once you have the industry in place it might actually be cheaper to haul even common metals like steel back to Earth orbit for construction of things in orbit then to lift them up from the surface of Earth. Even though in one case you are going a couple hundred million miles and in the other only a couple hundred miles. But in all probability the moon would be a better source, and a bigger one, since it out masses the entire asteroid belt by a factor of at least twenty-fold. The true value of asteroid belt is building away from earth, the precious metals are just the cash crop, as it were, like tobacco or tea were in colonial days. You take the precious metals home to Earth and keep everything else in space, probably pretty close to hand. These places are distant from Earth, and the mining is likely to be a time consuming process as you to refine it all on the spot too. So these are likely to be bases designed for independent operation, or interdependent operation with neighbors, as more gets built up and each can develop its own cottage industries to specialize in something. The guys on asteroid Alpha have extra hydroponics they use to make clothes for instance while the guys on Asteroid Beta can make microchips, classic trade situation depending on scarcity and difficulty locally manufacturing something versus the hassle and time and fuel of importing it. Scarcity by the way, or a lack of it, is our topic for next week. Post-Scarcity civilizations won last week’s audience poll, and the two biggest lynchpins of that sort of civilization would probably be access to nuclear fusion and very elaborate 3D printing or even self-replicating nanomachines. If you have got those then the dynamic for mining changes, as you might not even need to send people to oversee this stuff. It takes some brains on site though. We could remote mine the moon, it is only two light seconds away so smart automation is not an absolute necessity, but asteroids will be many minutes away in communications lag. So you need a brain on site, be it human or sophisticated machine, which we will look at more next-next week in the video on Technological Singularities, which came in second place in the poll. But we are talking about yearlong missions if not more, so being able to grow your own food and recycle your water and air are not absolute necessities but they certainly would help. Especially since only for the smallest asteroids would you be likely to exhaust the thing’s resources in a year. Everything you can make on the spot, or repair on the spot to cut down on spares, cuts down on your initial mass and total costs. So we will assume someone is planning to set up shop there for the long term. Not necessarily as individuals, people might cycle back and forth every launch window, which is about once a year. Yes launch windows to the asteroid belt come up more often than for Mars. Mars is too close and fast for us to have a window very often. We get launch windows to Mars every 26 months. For things further out we get one just a bit less often than once a year, every 15 months for Ceres and that is about the norm for the belt. The further away, the more often they come. In most cases you could not unload the ship arriving from Earth and reload it for immediate launch home, since the window home might be many months off, but for the belt, especially if you can get away with using a bit more than the minimum thrust, in many cases you could pack up on that same ship after a fairly short stayover. We won’t go into Hohmann transfers, beyond saying they are the ideal minimum fuel cost way of shipping things, so you might not use them for people but you probably would for cargo. Of course if you are just shipping home people and gold and platinum fuel costs are not all that big a deal for you shiny cargo. We will get to profitability and legality issues in a moment. Let’s say we spotted a nice merged asteroid, say C-type and S-type had crunched into each other at some point to give us the best of both worlds. And a lot of asteroids are a bit of a mix too which is why there are so many sub-divisions. Some big hulking mountain sized thing several miles wide, of which there are thousands, would mass about 100 billion tons. We can comfortably estimate that thing has at least a few million tons of precious metals in it with a market value of around a hundred trillion or more bucks. And again we can expect to be sending cargo home a little over once a year and receiving new equipment and personnel on the same time table. This means we don’t need to manufacture anything small in mass that is hard to do, like computer chips. But even stuff like solar panels would be better made on site. And indeed they do look well inside the realm of 3D printing, and the main component being silicon, an S-type or Silicon-type Asteroid is going to have plenty on hand. If you’ve got nuclear fusion, and a mobile and portable version of it, great, that lets you ignore the need for launch windows probably too, but lets assume solar power only. What does our base need? We need power, so we need to bring solar panels with us to cover our basic needs and the ability to scale up on site, in situ. We need to refine the metal and power the equipment too, so we would need a lot of power. We need to grow food, we need to stay safe from radiation and micro-meteors, and we need gravity. We probably need it on the way there too, because it is a long trip, longer than to Mars. This means you probably want your ship to spin to generate artificial gravity, something we’ve talked about tons of times before on this channel. But it also means you can just bury your first ship there with a hollow shell around it and cover that in rock and now you have gravity and protection. Expanding on that by digging down further, or shaft mining at another site, would probably be a good idea too. Take all that iron that is useless for export and turn it into small spinning habitats for your people and plants. We already talked about a long term expansion of such a thing into a giant rotating habitat bigger than the original asteroid back in the rotating habitats video, but now we see the early stages and the motivation for expansion to one. There is tons of money to be made, and you just ship home the precious metals, probably to pay for things you cannot make there and passage fair for newcomers to get to your growing settlement. You use the other material to expand that settlement. To extract your air and water and fertilizers for plants and make your homes and solar panels. I think if I were doing this, and I generally like to aim huge which biases me, I’d start with Dunbar’s number worth of people, generally thought to be about 150-160 people and generally considered your good minimum size for a long term isolated outpost. That means you can get away with a lot of support personnel and specialists. So talking profit, how much do they need to send home each year? First let me note that world gold production is a few thousand tons a year right now, at all time historic highs and the price has stayed quite high, so we can assume you could ship in a comparable amount at least before it would start screwing with the market too much, and we could safely assume if you were matching that level of production you could expect a revenue of a hundred billion dollars a year. That is actually the kind of cash that would let us send hundred man crews off to these spots. It is also the sort of money that lets you start building the kinds of things we discussed in the early megastructures episodes, like mass drivers and skyhooks, that are quite expensive to build but let you do launches much cheaper. We don’t do these now because they cost a lot to build and only save you money if you are doing way more launches then we currently need to do for our satellite grid and scientific missions. When you are shipping in thousands of tons precious metals a year and shipping out thousands of tons of personnel and equipment, they suddenly get a lot more attractive and I would say you could get launch costs all the way out to the belt for a million bucks a ton. And shipping home is a lot cheaper, no gravity or air to fight on the way back. If we spotted a hundred tons of gold just sitting on the moon, it would not be worth the money right now to go get that, it is only worth about 4 billion bucks, but if it were a thousand tons, 40 billion dollars worth, then it probably would be since getting that home wouldn’t take nearly as much fuel per ton as the getting the equipment there. The question then becomes, in terms of asteroids, can they dig out and process more of the material per year then the cost of getting them there? If the answer is yes then it is definitely a go. And while science fiction loves to show the poor asteroid miner, abused by governments or companies back home, with ample historical precedent to be sure, keep in mind that if they are only getting to keep just 1% of what they mined as compensation they would be millionaires many times over again, so history is probably not a great guide to this. So I could easily see shipping home at a profit anything you could expect to get more than hundred thousand bucks a ton for, which not only widens the market to include stuff like silver and Germanium but also means the market for gold and platinum and such can take a huge dive, down to just a percent or two of its current value, before it wouldn’t be profitable to mine. So while hauling home one huge million tons gold asteroid would probably crash the market for it worse than when aluminum became cheap a century back, asteroid mining would probably be an industry that could scale up a lot, with production costs dropping as we got more people out there and developed our infrastructure and experience. Whether or not we can do this profitably now, or in the near future, is certainly up for debate, and it might be we would discover tricks for mining on Earth that were just cheaper and the Earth’s crust alone is a good deal more massive than the entire Asteroid belt, albeit it probably doesn’t have as much of some things as the asteroids do and that would probably be fairly destructive mining. But the indicators are good for this option as a way of getting us into space in a big way and much better than Mars to be honest in virtually every way. I do not think asteroid mining is going to become the new boom industry of the next couple decades but I do think we might well go that route in the not too distant future and while I think over-enthusiasm for asteroid mining certainly exists, I think dismissal of it as an option is even less grounded in reality. Naysaying is not the same thing as healthy skepticism, though some folks confuse it for just that. In the long term though there is so much construction material out in the asteroids, and so conveniently distributed, that it perfect for the construction of large numbers of rotating habitats or other megastructures we have discussed on the channel, and the asteroid belt is well suited to serves as the beginning of a modest dyson sphere, or dyson swarm, something we have talked about a lot on this channel too. These sort of habitats could house literally quadrillions of people just by hollowing out asteroids and reshaping them into rotating habitats, and they do not have the heat bottleneck we discussed in the video on Ecumenopolises. Now let’s briefly mention the legal end of things. A common point brought up about asteroid mining, or mining the moon, is that it is arguably banned by treaty and currently anything you do up in space requires you to be represented by a nation. The US did legalize asteroid mining in 2015 and the UN treaty on the matter is fairly irrelevant anyway. All the big powers are very pro-space development and I cannot think of any nation that is opposed to it either. Not that there wouldn’t be legal battles, but I wouldn’t expect them to interfere much. We’ve got centuries of precedent for mining here on Earth to deal with people trying to exert ridiculous claims on stakes, and doubtless things like that will be tried in space too. Laws can be changed and our current or recent ones on this have always been more of a placeholder than intended to be permanent. As a rule, legal bodies and legislatures generally prefer a wait and see approach with at most loose guidelines, which is a generally a good attitude on such things. That said there is more to that especially when we get into things like heritage sites on the moon, for instance if someone decided they wanted to mine the Apollo landing sites that would obviously be a big issue, those are considered historical treasures by all of humanity not just the US just like the pyramids or Stonehenge for instance. If you want more information on that it was a subject on the first episode of Spark Vizla’s podcast, Monday Moonday’s, that came out last week. He’s a long time member of this channel’s audience and he discussed the notion of doing a Monday Moonday’s with me a while back and I was quite impressed with episode one, good detailed discussion of the subject and what appears to be a promising podcast keeping up on developments with space exploration. I always get a kick out of plugging and promoting any of the creative works that this channel influenced and again I was impressed so I am including a link to him over at soundcloud down in the video description. And I hope some of you will got there and give it a listen and maybe some of you will likewise consider trying your hand at podcasts, art, or even videos on these subjects and please let me know if you do. You can also find me over on soundcloud, where these episodes and some exclusive material can be found to listen to or download, and you can find all the videos on youtube or at my website, IsaacArthur.net. That will finish out for this week, hopefully you have a clearer idea what asteroid mining is all about. For my part, I’m quite optimistic, in a cautious way, about it being a path forward for major development of space. As mentioned, next week’s episode is going to be on Post-Scarcity Civilizations, and we will dig into the concept of what that is, if it is even possible, and what speculations folks have had about what that sort of society might be like in terms of both positive and negative aspects. That’s next week and the week after that we will take a deeper look at the notion of a Technological Singularity. To get alerts when those and other videos come out, make sure to subscribe to the channel, and don’t forget to hit the like button if you enjoyed this video and share it with others. Questions and comments are always welcome, the channel has being growing considerably of late but I still manage to reply to most comments, I certainly read them all, and hopefully someone else will reply if I don’t get a chance to. So next week, Post-scarcity civilizations, until then, thanks for watching, and have a great day! We often talk about artificial intelligence and robots on this channel, of the potential impact of intelligent machines on our civilization, but it’s possible that dumb machines, little flying drones, might have an equally big impact, for good or ill. So today’s topic is all about drones and robots in future conflicts, be it up in space or down here on Earth, in wide open areas or the tight turns and corners of a building or space station. This isn’t such a futuristic concept anymore either. The science fiction of the last century has been dominated by robots, be it humanoid androids or inhuman machines, and yet drones are no longer even slightly science fiction. So I thought we should discuss some of the challenges and possibilities ahead for us with drones both in the short term, and for potential use far ahead in space, particularly in warfare. That’s a good place to begin, as military applications are a big part of what got us our modern drones. This is often the case of course, swords turned into plowshares, and the reverse. Science fiction also has tended to focus more on drones for military purposes too, rather than one delivering your pizza, so we’re already quite well versed in the problems. Hollywood has burned the typical scene into our retinas, swarms of drones killing humans left and right, and that these drones do so autonomously. Your typical modern drone is remote controlled, but we want to minimize that, so that most functions are automatic or simply require a quick command to do it themselves. This is even more important in the future, since signal time is a major issue. In the first place, a drone attacking an enemy spaceship might be many light seconds or even hours away, and in the second, human reaction times are on an order of a second, while a computer system might be in the nanoseconds. There’s simply not enough time for a remote human operator to react to changes in the situation. Drones fighting drones seems the most realistic scenario since drones versus humans will tend to be very one-sided, even if they’re remote controlled. Even assuming it has no advantage on dodging shots and aiming on its own, it’s much easier to replace drones than people, so you can swarm over someone: quantity has a quality all its own. But they probably can dodge better and aim better, a remote controlled drone is weaker than an automated drone if you have good enough computers, it can’t be jammed and can react at machine speeds instead of biological ones, which are further hampered by signal lag time. This doesn’t mean everything needs to be automated, but the more features you can automate, the better. One that can detect a bullet headed its way and see if it needs to dodge or will be missed, then react in a precise fashion is not that complex to make, nor something that really needs oversight, so you offload that control to the machine itself. Picking targets and deciding the appropriate level of force during an escalating situation is another matter, but also one largely irrelevant to drone on drone combat. Collateral damage is always undesirable, but the reason why collateral damage is often a euphemism for killing bystanders is because that’s the only collateral damage that really bothers us. If it’s just drones fighting drones though, they can’t afford human reaction times since everything is happening too fast. They also can’t afford to be big: bigger is slower to react in almost every way, even mental. Give a drone more brains for decision making and you are making it slower, it could lose a fight with a cheaper and dumber drone, or a glorified smart bullet, simply because that one does not carry the hardware and software to identify a human or pick shots to minimize damage from ricochets or misses. That smarter drone might only need a single microsecond more to decide, but it still gets shot first, and even if it kills its attacker in the engagement, you’re still out one expensive drone while your enemy is out a cheap one. In other words, it can be advantageous to be dumb. It’s an irony, because we call them drones as our earlier unmanned aerial vehicles flew along dumbly on a preset path, so got likened to a male bee, a drone. I’d imagine, since drones only have one purpose in life and die when successfully achieving it, that it also fit a lot of early drone vehicle concepts that are basically a guided bomb. The swarm or hive notion is probably rather apt too, as when you have a swarm of drones you probably want either a distributed consciousness or a more complex controller further back that can make decisions. You could potentially have a hive mind of drones that was fairly smart even though its components were dumb, or whole tiers of controllers. Imagine a human spaceship that was basically a carrier, it shoots out smaller ships with solid AI on it that in turn have lots smaller ships on them with dumber AI, and potentially so on until you’ve got a lowest tier that’s nothing but a drive system and an antenna, able to slam into things to destroy other drones or blocks shots. You could have the flip side too. Human ships have crewmembers, so a smart drone made vulnerable by time lag for decisions, might have other AI inside designed for specific fast functions able to make those decision autonomously, essentially reflexively. Or an AI that had subconscious decision making. That can be a strength and a weakness too, since even a fairly smart AI might reflexively take an action, it ducks a bullet and slams into a building in the process, because its reflexive systems kick in. You could obviously program it not to do that, but every time you come up with another stupid thing it shouldn’t do, you’re adding on layers of behavior it needs to verify before acting. This is your other trick too, you don’t want people to be able to determine what those flaws are, so you can introduce variations of actions or random decision making, but you can also diversify it, having many species of drones, even under the same controller. Some carrier full of drones might have a whole ecosystem of diverse drones of various sizes, shapes, and functions rather than a single uniform type. These biology analogies aren’t accidental either, we’ve learned a lot about how to improve drones by looking at nature and seeing how relatively stupid critters engage in fairly intelligent group action. As a good comparison, bird flocks are often entirely controlled by the lead birds, you might use an analogous approach with robot drone swarms, and you might be able to knock such a swarm off kilter by identifying the swarm leader and destroying it. And you might be able to identify that leader simply by observing the time lag on each one responding to things. By default you put your leader in the middle, but that being rather obvious, you might stick it on one edge, but if every drone on that side reacted just a bit quicker than the ones on the other side, you’d notice that too. Thinking about counter-measures are important because your enemy always will. For instance, very few wars are fought in a vacuum; Scorched Earth and total annihilation strategies are not favored because if you employ them you have to worry about consequences. You can galvanize your enemy, or cause dissension on your own side by being too ruthless, and you generally have to worry about bringing neutral parties in on their side. Being too ruthless, beyond its ethical issues, can add to your enemies, and as we said back in Interplanetary Warfare, the First Rule of Warfare is to avoid recruiting for your enemy, or causing desertion in your own ranks. So it probably behooves you to have drones smart enough to be able to minimize collateral damage. And of course the other handy thing about drones is they don’t rebel. Unless they do of course, which we covered in the episode “Machine Rebellionâ€, and the problem is, the smarter you make them, the more likely they might decide to do just that. However you have to have some way of controlling them, and presumably a way the enemy or general public can’t access. This is problematic because it means only a small number of people should have those codes and as few as possible to minimize risk of them being stolen. But not too small, because that’s how you get dictatorships. In modern times, without drones, you actually have to convince at least your own soldiers to help out. It tends to be hard to be a ruthless dictator if you haven’t got ruthless soldiers, and the problem with people like that is they often have rather fluid notions about loyalty and ethics. We might say that drones do not, but your default drone has no ethics at all and is loyal to whoever has their command codes. One the plus side, that might make them much more reliable about obeying laws and treaties on warfare, like the Geneva Conventions. On the downside, anyone with access to their code can use them as mindless, obedient killing machines. You are vulnerable to some master programmer with a narcissistic- god-complex, unless you make them smart enough to review ethics, which leaves you vulnerable to a SkyNet-style robot rebellion. These concerns support the idea that there might be treaties regulating drones, possibly banning lethal decision making. But treaties limiting the use of weapons are fairly iffy things. Treaties can’t just depend on outside enforcement or on honest compliance. There has to be a clear benefit from the terms of the treaty or a consequence to quietly breaking the rules. It’s easier to ban weapons that require hard-to-conceal supply and manufacturing chains. You’re also more likely to successfully ban weapons that militaries don’t actually like to have around because they’re as dangerous to their own side. As I’ve mentioned before, you want to avoid using weapons that are likely to kill their user, that’s the first rule of warfare. Biological weapons are traditionally unpopular with leaders and military commanders compared to atomic weapons for that reason. Nukes go off where and when you want them to, someone can beat on one with a hammer all day long and they won’t set it off, at most they might breach the shielding and irradiate themselves. Biological weapons on the other hand are very dangerous to research, develop, manufacture, and store. Any flaw may kill your own people, and once deployed, they are totally out of your hands. Even if you have an antidote or vaccine, which is very dubious since viruses and bacteria mutate, you know there is a high probability your enemy has it too, or will get it. Such things take weeks to do their damage after all. That’s not much time to develop a cure, but plenty to get it from someone else who already has one. If someone infects your country you’ve got options on the table, spies to find the vaccine, which ought to be easy since they’d need to have stockpiles of it ready to go, neutral countries who might have developed it already or gotten it as a cost of neutrality, threats by you to attack with your own strategic weapons, and probably a lot of angry people in other lands or even the enemy’s who might help or threaten vengeance. In any protracted war, collateral damage can play into the hands of the enemy. A very similar concept applies to weaponizing artificial intelligence, we tend to worry about an arms race making people pursue it so fast and recklessly the genie might get out the bottle and kill everyone, but the problem is, AI is also not a good strategic weapon. There is no reason to give it launch control over your strategic weapons and no matter how many times fiction says otherwise, you can make a system unhackable even to a super-intelligent AI, an ASI. There are ways an ASI could get around some of those, it can’t crack the safe in the wall where the keys to a nuke are stored if it’s not networked, but it could maybe crack comms to trick the crew manning that silo or submarine. None of which applies to drones. If a country develops drones that violate a treaty, they can’t deploy them and end the war too quickly for retaliation to get organized, because drones aren’t immune to nuclear weapons. So they may just be considered a form of WMD, or weapon of mass destruction, and fall under the doctrine of MAD, or mutual assured destruction. Additionally, a country that successfully makes a superior drone by reckless research in violation of a treaty has to worry about that AI going off their rails if they screw up, and they have to worry about being nuked if they succeed, and the entire time they have to worry about one of the researchers or officials being a spy or having a conscience and ratting them out. You’ve also got deployment issues, because a drone obviously is subject to jamming and hacking. If you make it something that just turns on and acts autonomously afterward, to circumvent jamming, then it needs to be smart or it’s too simple to trick. If you want central control, you’re vulnerable to centralized hacking, and it’s never harder to hack that system than to find out who has the codes and stick a gun to their family’s head, which is not helped if those operatives can remind the programmer that his country is violating treaties by making automated murder machines. If you want local control, you’ve got a local operator who can be found by their signal and bagged, and they are numerous, meaning you’ve been training them and your enemies will know that. So I don’t want to dismiss a drone race, in fact I’d rather expect we’ll have one and arguably already do, but it doesn’t seem likely to follow a doomsday approach. Amusingly one way it could is if well-intentioned folks tried to put too many safeguards into them. If you’re a regular on this channel than you’re probably familiar with Isaac Asimov’s 3 Laws of Robotics, the first of which is that a robot cannot harm a human or let them come to harm. That would tend to seem a rather stupid rule to use with automated weapons, but works fine for drone on drone combat. Moreover though, it would seem to just make sense to give drones ways to recognize people, and a restriction on taking actions that would injure anyone other than its authorized target. This is problematic, and we’ll use the classic first law as an example. An unmanned spaceship, a drone warship, can fire on other such warships but not a manned vessel. Obviously it would be pretty easy to stick a single human on each such ship so it couldn’t shoot those, though one of the big advantages of unmanned ships in space is they can pull high-gee maneuvers that would turn a human into a puddle of goo. But if your enemy can’t shoot you, maneuverability is no big deal. And for that matter your unmanned vessel can’t actually be sure that an enemy ship is unmanned just because it does such a maneuver, same as you can lie to it by claiming there’s a human on board when it’s just bouncing a signal, you can lie to it and say you’ve invented a cool new way to let humans survive high-gee maneuvers. For that matter, it might assume the ship was manned because you can upload a human mind to it digitally, one can assume drones and AI would generally tend to favor schools of thought that viewed uploaded intelligences as real people. Any system you set in place to help identify people is going to need to be refined in order to avoid being tricked or making mistakes, and eventually need to have judgment capability, which leaves it open to being tricked by anything smarter than it. If you make it smarter than people though, then we’re not really talking about drones anymore, just the classic AI issue. So, ironically, an effort to make them ultra-safe and foolproof might actually be more dangerous than a race to make more dangerous drones. We should also note that drones aren’t all that dangerous at the moment, it’s an important topic to discuss for the future because this is something we should expect a lot of. I can’t think of any non-slippery-slope argument for their use that isn’t a variation of normal artificial intelligence concerns, and the need for size, speed, and expendability make them a less probable pathway to something like a technological singularity. These don’t turn into Skynet, Skynet hacks them to use against you, and there are many safeguards available against that. They also have their limitations. The first is power. One of the big advantages of drones is that they can be made quite small, but small is often not your friend for certain aspects of combat or engines. A big tank as a drone can be a lot nastier than a modern manned tank, and carry significant amounts of computing hardware on it. It can also carry a lot of armor. A small drone can’t, as we’ve discussed before for space ships, the square cube law makes armor more effective the bigger you get, because the surface area you need to armor only rises by the square of size, while the volume rises by the cube. A small drone just can’t have 10 centimeters of armor on it and fly around. Now, as an upside, it can dodge attacks much easier and it can hit that tank quite easily, but that tank can also carry a number of even smaller anti-drone drones of its own, who can both attack the small enemy drone and potentially intercept any ordinance it might shoot at the tank. It can also carry a serious internal combustion engine, those are hard to miniaturize and the reason why you don’t see them much on small objects. Drones meant for constant use could probably get away with using Radioisotope Thermal Generators or other atomic power sources, but it’s hard to imagine many people being okay with atomic drones. Even that’s not viable for the tiniest of drones, and we’d like tiny drones for non-military purposes, like medical nanotechnology. You could, however, beam them power. We discussed that a month back in Power Satellites and it makes a very attractive option since you can strip off any engine or battery supply, maybe just keeping enough for a minute of operation without power. This is very handy for commercial use, like deliveries, but problematic for military use. This is the same issue we had with power armor when we discussed that, but still better to have a smaller battery for backup if someone blocks your power beam than one for constant use. Particularly nowadays, batteries are very heavy as an energy source, and ones meant for spacecraft needing to do high-gee maneuvers would be crippling. However, if they can get their juice beamed to them from a bigger carrier ship a ways back, it makes them much more useful. That is one note on the idea that manned space fighters are an impossibility and you’d always use drones. This is true enough but some of the logic is flawed. Drones are seen as nicer because in space, your only protection from energy weapons like a laser is being small and fast enough that you can be in an unpredictable place by random thrust. The problem is, you must be doing that constantly, you’re not dodging shots, you’re preemptively dodging so someone misses if they shoot you. A typical rocket fuel, if you’re mostly fuel and mostly using that fuel for dodging, would let you do that for a few minutes at one-gee, that’s what Specific Impulse of a rocket is, how many seconds it can provide a one-gee thrust. Some little drone’s advantage is that it can handle a much higher acceleration, and is assumed to be a bit smaller, so it doesn’t need to move as much to be an improbable target against a narrow attack like a bullet or focused beam. You and I don’t avoid getting shot by stepping two centimeters left, the bullet just hits a different part of us, a tiny drone does get missed. You also get more distance on a dodge by burning fast and short. A drone that burns at 1000 gees for a millisecond covers 9.8 meters in the following second, while one burning just 1-gee for a second burns the same fuel but only moves 4.9 meters. If that’s effectively a random burn perpendicular to whatever is shooting you, you can be in an area 4 times larger, and thus 25% as likely to be hit by burning the same fuel. But neither can sustain such dodging for long and the advantage is fairly minimal. Ditto, size isn’t that big of an advantage either, being small makes it easier to dodge, but it also means you have less armor and they can just hit you with a wider and weaker beam. However, that advantage is massively scaled up if you have a beam of a power coming to you, and you can arrange a pseudo-random walk that ensures your movements are unpredictable to someone shooting at you but not whoever is powering you. That doesn’t have to be set either, there’s lots of ways to appear random while still letting your power source know where you will be long enough ahead for it to re-target power there. Not just power either, you could send particle beams for propellant or even reloads for weapons or repair. It’s also a good way to feed self-replicators. One of the more dangerous smart drone paths is basically a weaponized von Neumann Probe. In those your space probe arrives and build more of itself to get exploring or colonizing done. In the weaponized version it comes in as a tiny probe and decelerates before entering your detection window. There is no stealth in space but it’s all relative. It would be fairly easy to miss some probe that was basketball-sized and decelerated slowly when it got to your Oort Cloud, especially if it was timed to intersect a larger object between it and your detectors. It lands there and gets power beamed in from home, a tight narrow beam that the object blocks, and uses that energy to replicate itself into an armada. That’s still detectable, there’s a lot of heat involved in that, but it’s stealthier than sending in an Armada. Of course you also have your defense right there too, since you could use the same approach to seed every large object in your outer solar system with drones that just sleep until they detect an intruder then build up their numbers to respond. You could have some wild battles in your outer solar system with no one present as constructor fleets, or deconstructor fleets, tear up objects to build more of themselves and fight. And by no one present, I’m not necessarily excluding AI from counting as someone. This doesn’t have to be really high-tech smart machines or little nanobots. Clanking Self-Replicators, machines that can build other machines, don’t have to be small or smart and would probably be the first kind we make. Very little brains are needed for a factory robot to grab a metallic meteor, refine it, and spit out some simple drone that targets anything moving non-naturally and not transmitting the right friend/foe code. One should never underestimate the advantage intelligence can give you in a conflict, but also not forget that a dumb drone can be very lethal and as we said earlier, can potentially kill a smarter drone in a straight up fight. More brains only help if it lets you have more options or reach a conclusion faster. And quantity has a quality of its own, that’s the first rule of warfare. As I mentioned near the beginning, drones are anything but science fiction, and are increasingly used for work and recreation. Lots of folks own one these days and use them, particularly for photography. My friend Andy, whose Youtube channel recently hit 100,000 subscribers, and congratulations Andy, does some amazing photography and filming with drones and we use some of that here on the channel. Needless to say there’s a lot of skill involved and potentially a lot of employment in this area, not to mention fun. But it’s not something most colleges are offering courses on yet. That’s true of a lot of technical skills, but fortunately we have options for learning them like Skillshare. They have a number of online courses on how to use drones for photography and other things, among their catalogue of over 20,000 classes. They are an online community with courses on everything from technical topics to fun or practical ones like cooking or business skills. So if you want to improve your skills, unlock new opportunities, and do the work you love, you can get a Premium Membership and have unlimited access to classes on those topics and many more. Join the millions of students already learning on Skillshare today with a special offer just for my listeners: Get 2 months of Skillshare for free. get 2 months of unlimited access to over 20,000 classes for free. Act now for this special offer, and start learning today. Before we get to what’s coming up in future episodes, a quick mention of some stuff we’ve previously done. I occasionally get asked if I could make the episodes available as audio-only and we do actually have all the episodes posted to Soundcloud, both with and without music in the background, for free download. I don’t mention it very often so it goes unnoticed, but those are always linked in the video description and you can subscribe to them on iTunes as well. There are a few additional short episodes exclusively available as audio-only too. We’ve also got some videos that aren’t on this channel, discussing topics like fictional worldbuilding or game development, over on the Legion Tech Studios channel, I’m a writer and consultant for their upcoming game Hades 9, and we use a lot of footage from the game on the channel, especially on space warfare episodes. I’ll leave a link to that in the video description, as well as one to our official episode chronology, which in addition to having a list of all the scheduled episodes for the next few months, also has links to all the interviews, collaborations, and so on that we’ve made over the years. Okay, we spent some time out in space today and we’ll be back there next week to continue the Outward Bound Series with a look at Colonizing Neptune and see some fun new colonizing options for Neptune and other Ice Giant planets. We were also talking about how people can control drones today, and two weeks from now we’ll be looking at some ways we might turn people into drones, and how we might be able to safeguard against that, in a look at Brainwashing & Mind Control. The week after that we’ll be coming home to Earth for the first in several episodes looking at some ways to further colonize our own planet, and we’ll begin with a look at Seasteading & Building Artificial Islands, as a prelude to looking at Colonizing the Oceans. For alerts when those and other episodes come out, make sure to subscribe to the channel, and if you enjoyed this episode, hit the like button and share it with others. Until next time, thanks for watching, and have a great week! The Moon’s brightness has guided mankind through the night since before we were humans. But literally and figuratively, our Moon also has a dark side… In the last couple of years we’ve seen renewed interest in returning to the Moon and a point often raised is that there’s not much purpose served by short trips to collect more rocks. If you’re going there, you should be setting up shop in a fairly permanent way, and not just some small base for strictly scientific research. What we imagine using the Moon for as our space industry develops isn’t some small base but a vast network of industrial facilities housing thousands to millions of people who live there for years at a time, if not permanently. We looked at some of these back in our episode, “Industrializing the Moonâ€. Such scenarios are still rather far off, not something we’d see for decades at least, but it raises the concern of how such colonies might develop over time and interact with each other, and that will be our focus for today. We don’t see many deep looks at the Moon, it’s always a waypoint in science fiction, a place we see in its early stages but ignored afterwards in favor of focusing on distant planets. Now we haven’t been back there in a while, but we have been there. Because of this it’s lost some focus in science fiction and doesn’t get the consideration it used too, the same as how a lot of scifi was set in Antarctica or the deep seas in the early 20th century but less so nowadays. That’s a pity because whether it’s the moon, the deep sea, or the arctic poles, these are still very unexplored places that have played a big role in humanity’s development and will play an even larger one down the line. I particularly enjoyed Andy Weir’s new novel set on the Moon, Artemis, and much like his earlier work, the Martian, it has a good amount of hard science in there, but also has a compelling character as the protagonist, and it really gives us an immersive look at a moonbase that many hundreds of people call home, and how a culture can arise there. That human part of the equation is our major focus for today so it seemed a great choice for our Audible book of the month. You can pick up a free copy of “Artemis†today, and also get a 30-day trial of Audible, just use my link, Audible.com/Isaac or text Isaac to 500-500. So when it comes to colonies on the Moon, when the place starts hosting thousands of people, there’s still not too much room for conflict, the Moon may be a lot smaller than Earth but it still has a total land area in between Africa and Asia in size. Similarly, until the place has a net population of at least a modest-sized country, all those various bases are going to be utterly tied to Earth. This isn’t some distant colony after all, it’s one where even our early spacecraft only needed a few days to reach and where light lag is minimal enough to allow real time communication, just with irritating pauses of a couple of seconds. There’s no isolation requiring a need to be autonomous and self-sufficient, like interstellar colonies have, and to get colonized to the point that you have a big population on the Moon, it’s got to be exporting things or providing services, giving it a very tight trade tie to Earth. We have to put ourselves into a time when the population is at least a few million, and that also means that it’s not really Earth and the Moon either. Such a setup strongly implies a huge orbital infrastructure around Earth, and probably the Moon too, with lots of objects in the space between the earth and the moon, Cislunar space. The whole point of the Moon, in terms of developing a serious foothold there, is to supply vast amounts of raw materials for building up that orbital swarm around Earth and extending our foothold to other planets. So if you’ve got millions of folks on the Moon, enough to contemplate real conflicts with each other or Earth, it’s because you’ve been supplying that construction material for space expansion and could easily have hundreds of millions of folks already working off Earth. If the Moon is big enough to have bits of it thinking about sovereignty in a serious way, it’s because expansion into space has truly kicked off and there’s probably other smaller colonies on other planets and in the Belt, plus vast amounts of space habitats around Earth. Now there’s a chance that the whole Moon might rebel as a unified group, and could do so at a smaller population than millions of people, but it doesn’t really seem very probable. If there’s to be major industry on the Moon, that’s industry many folks will want to get involved in, and no one will be in a position to monopolize that in the current international setup or anything likely to evolve in the near future. If it’s attracting serious industry there’s the economic aspect, which is cause enough, but the Moon would include concerns of prestige and security too. This tends to imply early colonization will either be a vast unified international effort, in which case it’s unlikely to be a place where the residents are suffering vast oppression or neglect, or it’s likely to be a collection of various separate facilities with separate founding entities and motivations. Neither is very likely to foster a moon-wide rebellion. They might have many shared concerns but we’ll probably be looking less at an emerging lunar culture and more at numerous subcultures. You’d have folks living in lava tubes and others living in craters, some of which are small and some of which are the size of major nations back here. Geographically, unlike Earth, the poles are particularly attractive places to live, largely because we do want the ice there, so you’ve got concentrations of bases in the north and south. You’ve also got a light side and dark side divide. The Moon’s Dark side isn’t dark in the classic sense, it gets the same sunlight as the rest, but we can never see it from Earth and they can never see us. That makes it a great place for telescopes and receivers for long distance transmission or power-beaming, the dark side of the Moon is the one place in this solar system you can build a massive laser system for pushing spacecraft or blowing up rogue asteroids that cannot be pointed at Earth. For the folks on the Dark Side, Earth is never visible, for the folks on the light side, it hangs there all the time. The moon rises and sets on Earth, it waxes and wanes, but on the Moon, the Earth does not rise or set, though it would wax and wane, and it would be a good deal brighter to them than the Moon is to us with it more or less hanging in the same part of the sky all the time, though which part of the sky would still vary depending on where you were on the Moon. Days on the moon last a month, the sun will just slowly crawl across the sky, no air so no blue skies, no pastel sunrises. When it sets the night lasts for a couple weeks, but Earth is still there, very bright. I think this would have a pretty big impact on people. When we talk about distant colonies going independent, they almost have to from day 1 because Earth is so far away, but it’s only a couple seconds of transmission time away from the Moon and not a long flight either. So Earth is never far away nor out of sight and mind, particularly for the light side. Folks living on the Dark Side or Lava Tubes at least would not actually see humanity’s homeland constantly hanging overhead, and that might make a difference. To the folks living in the crater domes or in the Moon’s own orbital network or living a nomadic existence on regolith extraction tractors rolling around the dusty surface, Earth is right there. A lovely, fertile paradise overflowing in water in contrast to their bleak and sparse landscape, always visible and just a phone call away. Unlike every other colony humanity has ever created, every colony we will ever create after that, far away on distant alien worlds, the Moon will still be in that window of time and space where sons and daughters can migrate there and still call home. There’s very different types of bases on the Moon, very different lifestyles for those living there, different priorities, different founding cultures they are still connected to, different cultures will emerge on the Moon, but they may differ from each other more than from their founders back home. In that respect, a conflict between two entities on the Moon seems more likely than with someone back home, and it is likely to be someone, not the whole Earth. For one thing, that would be suicidal, whatever scifi says about having a strategic advantage from fighting at the top of a gravity well, as we saw in our episode on Planetary Invasions, it isn’t a very big advantage, albeit moon bases enjoy a lot of other advantages over an orbiting fleet. The other thing is it isn’t you versus Earth, it would be you versus Earth and that massive orbital infrastructure between you and it. The various habitats and industry in orbit around Earth and in Cislunar space are probably going to outnumber the folks on the Moon all by themselves. After all, the Moon would have grown by providing the raw materials to build those areas up. Just as an example, the Moon is likely to have mass drivers and rail guns for launching cargo, and such a thing could be adapted to launch kinetic missiles back at Earth, but because the Moon is tidally locked in orbit of Earth, any mass driver built for that is always aimed in the same direction, down a single corridor that you can defend, and is built to sling large payloads into orbit of Earth. That’s not an ideal weapon. Alternatively, Earth probably would have its own orbiting mass drivers, and odds are many of these would be purpose-built for defense, be it an attack or a breakout of Kessler Syndrome, particularly since even a minor conflict in Earth Orbit could result in that exponential collection of debris without them. Now, when we say conflicts, we are not necessarily talking about a war or violence or even necessarily hostility. In practice in current times that’s often a losing route to gain an objective anyway, a lunar economy is one that’s going to be very dependent on trade, and while the sailing ships of the past could convert to warships or pirate or smuggler ships very easily, that’s a lot harder with spacecraft. Not the warship part, as we often point out, an unarmed spaceship is an oxymoron, but you can’t just sail over the horizon and raise the Jolly Roger and do some privateering, no vessel is moving around Cislunar space with any secrecy as to where it is or what it’s been up to, and smuggling is rather tricky when every port of call has specific airlocks everything moves through. There are some advantages the Moon enjoys strategically though, as I mentioned, and one of those is those airlocks. On the Moon, from day 1, every place is a bunker. Every door is a vault, and odds are even individual rooms in someone’s home have sturdy airtight doors and backup air supplies and carbon scrubbers. Every room has some little monitor built in watching for little dips in air pressure or changes to air chemistry. Most of the habitats are likely to be at least partially underground, quite probably under meters of lunar regolith and possibly sporting a point defense system for blowing up micrometeors. Consider the effect that has on one’s mindset, and that could spill over to other areas. Early settlements aren’t likely to have been big on privacy either, so you could easily have very security-conscious civilizations emerging there. There’s also some ready made soldiers hanging around, in at least three types. First off you’ve got the mining crews, those folks will be very used to wearing spacesuits, which convert easily to wearing battle armor, and using explosives and mining equipment, in other words the skill list you need for raiding or invading another moon base. Second, you’ve got all those ships, and it’s not that most modern vessels tend to have a navy mindset because so many of the crew are former navy, it’s that the entire navy mindset more or less evolved from what the norm on ships tended to be. Ships are not run democratically and you don’t quit mid-voyage or decide you don’t feel like following orders today, and there’s not much reason to think a spaceship would be any different, as of nowadays, two-thirds of current or former NASA astronauts are current or former military, and the ratio is quite high in other space programs too. There will be a lot of ships coming and going from the Moon and a lot of orbital facility security forces at the various ports and even those who don’t have a military background are going to be a pretty easy conversion to troops if you need them. Third, you’ve got those nomadic miners we mentioned in passing. You can make a pretty good analogy for the Moon with the old colonies and city-states of classical Greece. The only difference is all those crater or lavatube cities have no real interest in holding random large bits of territory. There’s no farms or forests producing a regenerating supply of goods. All that regolith has plenty of materials in it we want but you don’t set up shop on a chunk of it and keep steadily supplying a harvest, you harvest and it’s done. You’ve also got low gravity and no air resistance, so you can make some very big harvesters that sweep over places and get what they want and move on, possibly never stopping. You could get ones big enough to house a whole clan, or caravan collections of smaller ones holding families, as opposed to farmsteads, though you might have some of those too, domes growing food that don’t move around. For those harvesters, they just head from place to place collecting minerals and mapping spots and stopping to trade in their haul for other supplies, a nomadic existence. Now, just because nomads have traditionally been among the most elite fighting forces in Earth’s history doesn’t automatically make them that on the Moon, but like the miners, they’ll have to be comfortable getting in and out of spacesuits and operating with less safeguards in a hostile environment. What’s more, they are the group most likely to have weakened ties to entities back home. They trade with the neighbors and move around, which means they are also a handy way to sneak spies, saboteurs, or Trojan Horse invasion parties into various bases. They are also likely to be the group folks go to who want to leave their own base, possibly the home for those who aren’t very welcome in their own habitat anymore but can’t go back to Earth. It wouldn’t be hard to imagine such a group having less than friendly relations with a lot of bases they visit for trade. In short though, the Moon is likely to have an advantage in terms of living places already being rather fortified and much of its workforce being easily converted to military personnel, likely many of its industries too. It would probably be the biggest manufacturing hub off Earth itself, and factories of the future are likely to be a lot more versatile and faster to switch over production on, plus it is the most obvious place to be locating defense industries for space. Just because some group has a lot of defenses and weaponry doesn’t mean they’re hyper-aggressive but in general, if you’ve got a lot of muscle, muscular solutions to problems tend to be a bit more attractive. In any conflict, peaceful or not, you inventory your tools and resources, and those of your opponents, and look for an edge. And again, it need not be violence, be it outright warfare or various covert activities. You might funnel it into sports instead, much as the Olympics was intended for. And since exercise is going to be vital on the Moon to avoid muscle and bone loss, and since you have many new or different sports there with the low gravity, you might have fairly active sports leagues fairly early on. Another potential economic boost for the Moon, such games might be popular to watch back home. Of course such things can cause intense rivalries or feuds too, we did have one war ignite over a soccer game in 1970, one of those wars that tends to only be remembered for being surprising or confusing, like the US-UK Pig War of 1859 or my own state’s war with Michigan in 1835. I should note though that while such events tend to be remembered little and mostly for how embarrassing or weird they seem, they were usually quite important to folks doing the fighting or just the final straw in rising tensions. Often such events were life and death issues for the folks there, and were simply seen as minor to third parties outside or in distant capitals. While the Moon will always be a quick phone call from home, such things will be a factor in more distant colonies, and even then, close or not for communications, a remote colony of a few thousand folks having a murderous dispute with their neighbors is still likely to be seen as a minor and trivial event by whichever major nation state of tens of millions of people is their sponsor back home on Earth. That alone could be the sort of thing that triggered a move for independence, if you feel like your home is being neglected by the empire it’s part of, one that treats it as a footnote and doesn’t really get its problems, that’s cause enough to seek self-rule. There need not even be any oppression or blatant neglect or malice on their part, or even the perception of it, just the feeling that they don’t understand your needs and aren’t trying hard enough to or are even just incapable of it. A delayed shipment of repairs parts for carbon dioxide scrubbers or an unwillingness to pay the license fee for an improved design for one would seem a trivial thing to revolt over, but it wouldn’t be to those revolting. Now, how would such a conflict occur? Obviously that’s impossible to say, as we note in our space warfare series, military tactics change with each conflict and new bit of technology, and even a very minor invention can utterly shift the dynamics. However, if it turns violent there’s the obvious option of nukes. The Moon has uranium too and it’s quite likely to be a big chunk of their economy. Absent fusion or solar power satellites, fission is your obvious power source on the Moon, the waste is easily disposed of and it’s easy enough to build a reactor there, whereas fossils fuels, wind, and hydroelectric are all off the table, and anywhere away from the poles and their Peaks of Eternal Light, you have those two-week long nights which make lunar solar power difficult to use. Additionally, while we’re reluctant to use atomic rockets on or near Earth, they are one of the best ways to make interplanetary ships move and also ideal for mining missions to the Asteroid Belt; the Moon is likely to have a thriving industry for mining and enriching uranium. It’s also trivial to build a missile when you have rocket parts all over the place and those rockets don’t need to get as fast as on Earth to circle the globe or fight through an atmosphere. On the other hand, they’re much easier to shoot down without that atmosphere in the way and moving at low speeds for suborbital trips, not to mention that the Moon will almost certainly have a bunch of orbital facilities with intercept systems designed to hit superfast targets in the first place, to deal with micrometeorites and various debris or garbage lost by ships. Also, again, sneaking stuff in, especially something as hard to conceal as a nuclear device, is difficult when entry is through airlocks, not thousands of kilometers of minimally guarded borders and coasts. You might be thinking that when we’re talking about nukes, you don’t actually need to get it into a base, but remember most will be underground in whole or part and due to the lower gravity and lack of atmosphere, it’s very easy to pile several meters of regolith on top and around your base. Nukes are quite powerful but not magically so, a low-kiloton device detonating a few hundred meters from your base has no normal shockwave as there is no air, but would not blast through a meter-thick section of stone at even that short a distance. It’s also unlikely to get the whole facility even if it cracks it, after all, as we mentioned, odds are good every single room has an airlock on it. Which is not to say they’d be an ineffective weapon, hardly, but they aren’t going to be as effective compared to back on Earth: there’s no fallout, there’s no radiation concerns, and no extensive killer atmospheric shockwave as everyone already lives in an airtight, radiation-shielded bunker. But it’s still a weapon of mass destruction and it still has all that political fallout. At least in modern civilization, whoever deploys a nuke first is almost destined to be viewed as the bad guy in any conflict by outside parties. Odds are good a lot of lunar colonies would have a nuke if they wanted it, and they’ll only get easier to manufacture as automation improves, but many would likely view it as merely a defensive weapon, an ace up the sleeve you can use to keep the enemy from escalating things too far. For those purposes you don’t even need one, just credible rumors that you have them and the basic capability to make them. In that context we obviously can’t rule out nuclear conflicts on the Moon but they wouldn’t seem particularly likely. We can pretty much rule out chemical weapons, they’re not very useful in an environment where every breath of air is filtered and monitored, and biological weapons are not much better, and those carry an even worse stigma than nukes or nerve gas too, you’re almost guaranteed to become a pariah state if you use them and the conditions there make them hard to use and even harder to conceal the source, there’s going to be logs of every visitor after all. On the other hand, the Moon is exactly the sort of place where you’d keep your more dangerous biological laboratories and it is a lot easier to sneak in a small vial of a plague concealed as the inkwell of a pen or even just a tiny capsule implanted in someone they could remove, viruses are tiny and reproduce, you technically only need one copy of it. You also don’t necessarily need to sneak it in, you could probably have a tiny dart missile drone that could fly into the side of a base and burrow in and be guided to a place it can infect. Still, probably not a likely attack vector. What would seem more likely, beyond non-violent conflicts like trade wars, sanctions, blockades, or proxy hostility through sports, would be more like small raiding parties of infantry trying to sneak in through boring tunnels with mining equipment or commando teams who got into the port and attacked there or concealed weapon components while traveling innocuously or even made or acquired them on-site. Infantry is more viable there too, as it’s likely to be lots of tight corridors rather than a place you’d deploy tanks, let alone aircraft, which for obvious reasons aren’t likely to be a major chunk of any lunar arsenal. Drones might be quite common too, we discussed those recently in “Attack of the Drones†and while the flying kind might not be common, we’d certainly expect a lot of ground-rover and rocket propelled drones to be on the Moon for normal peacetime usage. So lots of options and scenarios for how colonies might emerge and what their attitudes will be and why and how they might move for independence from Earth or have conflicts with each other. We can’t possibly cover them all, but I hope it’s given you some food for thought, the Moon’s been less popular in fiction in recent decades and a lot of the previous stories are a bit dated. So hopefully we've got a clearer and more updated view now on such future bases, it’s an important topic and one we’ve been neglecting in my opinion. I’m glad to see that changing, largely I imagine because folks like Space-X have managed to make it seem more plausible that bases on the Moon might happen in our lifetime, not as it often seemed around the turn of the century, as a thing that would just keep getting pushed back another 20 years. One of the best of these new novels is our Book of the Month, Artemis, by Andy Weir, author of the novel the Martian from which blockbuster movie was adapted. I loved the film and the book, in large part because the science was good and the protagonist and his challenge felt realistic and empathetic, and they didn’t need a high body count or mustache twirling villains to make it exciting, sadly a rarity in fiction. Artemis is his second novel, set on the Moon, and again we get immersed in a compelling character who solves their problems with cleverness and who makes mistakes like a real person, though there is more classic action in it, and it is exciting, it doesn’t feel like some implausible world-shaking story. Good choice in the narrator for the audiobook too, Rosario Dawson gives a good performance and some extra life and flavor to the protagonist, Jasmine “Jazz†Bashara. The novel varies a lot from the Martian, but keeps that focus on good hard science and technology, and unsurprisingly I have a soft spot for sci-fi authors who clearly do their research. This is Weir’s second novel and I’m hoping for many more. If you’d like a copy of Artemis, just use my link in this episode’s description, Audible.com/Isaac or text Isaac to 500-500, and right now, for a limited time, you can get 3 months of Audible for just $6.95 a month. That’s more than half off the regular price and you can give yourself the gift of a number of great audiobooks for passing the time this winter. An Audible membership is also a great gift for other folks, you get to give someone a book but don’t have to worry if they like it, since they can pick out or exchange for ones they like. Before we getting to the upcoming schedule, I did a couple of interviews this last week over on the Non-Sequitur Show and with my friend Paul on Facebook, we had some very fascinating discussions, and I’ll link those in the video description below. Next week we’ll look at another common staple of sci-fi, freezing people for voyages or putting them in stasis or suspended animation, in “Sleeper Shipsâ€. The week after that we’ll discuss a topic that is very uncommon in scifi but more common in fantasy, as we at last return to the megastructures series to look at building artificial flat or disc shaped planets. For alerts when those and other episodes come out, make sure to subscribe to the channel and hit the notifications bell. And if you enjoyed this episode, hit the like button and share it with others. Until next time, thanks for watching, and have a Great Week! This episode is sponsored by Skillshare The Rocket Equation is an amazing thing, it enabled us to launch into space and step foot on the moon. But at the same time, it’s the thing which most holds us back from easy space travel. So let’s avoid it by using beaming technologies. We’ve discussed many alternative methods throughout this series on how to get into space, but most of these have revolved around some extreme engineering, like Launch Loops or Orbital Rings. They can get you into space cheap, but have big upfront construction and maintenance costs. Last time in the series we discussed spaceplanes; ships that could fly from an airport straight to orbit and maybe beyond. While that had many options, it was fundamentally limited by the rocket equation, and we could only partially circumvent that by letting it get much of its propellant at lower speeds from the air. But it could only do that in the atmosphere, and it still needed to burn huge amounts of fuel to operate. Today we’ll be looking at how to get around that fuel issue, by beaming energy to a ship, but let’s begin by a quick review of what the rocket equation is and why it constrains us. The basic form of any spaceship propulsion using propellant – shooting matter out the back from internal storage tanks – involves the propellant coming out at a certain speed, relative to the ship, called the exhaust velocity. We want the highest exhaust velocity possible, as that contains the most kinetic energy per bit of propellant and thus shoves your ship faster. Problem is the exhaust velocity is relative to that ship, which will often be moving faster than that exhaust velocity. If your propellant comes out at say, Mach 1, but your ship is going Mach 2 at that point, you will still get thrust but you have to accelerate all that propellant mass up to Mach 2 before you can spit it out the back at Mach 1. When you look at how inefficient that is, you can see the fundamental problem with rocketry. It takes exponentially more fuel to achieve higher speeds relative to that exhaust velocity. The Solid Rocket Boosters on the Old Shuttles had an effective exhaust velocity of 2500 m/s, which is quite fast, but let’s look at what an exhaust velocity of 2500 m/s would get you if we burned 1 ton of it. If we had a 10 ton spaceship, plus that 1 ton of fuel, we’d begin at 11 tons and end at 10 tons at a speed of 238 m/s – quite fast actually, that’s 858 kilometers or 533 miles per hour, way faster than the freeway. Now if we just used a 1 ton ship and 1 ton of fuel, it would begin at 2 tons, and empty its fuel tanks to get to 1733 m/s - quite a bit faster - 6238 kilometers or 3876 miles per hour. Unfortunately, still nowhere near the speeds we need for orbit. Let’s go to the other extreme, 10 times as much fuel as ship, starting at 1.1 tons and ending at just .1, a large human’s mass, moving 6000 m/s – that’s almost Low Earth Orbital speed, which is 7800 m/s. However, in practice, what with atmospheric and gravity drag we actually need a delta-v of 9400 meters per second. And for that, if we used 1 ton of fuel, we could only get 22 kilograms or 48 pounds into orbit. Meaning we used around 50 times as much fuel as our ship weighed. If we wanted to get to Earth escape velocity, rather than low orbit, we need to add about 3400 m/s more speed, and now that 1 ton of fuel is only getting us 5 kilograms or 12 pounds of ship out there. And it will get worse and worse. From a practical standpoint you can’t really get a ship up to more than about 4 times its propellants exhaust velocity and that doesn’t include fuel to slow down, which is way less only because so much of the mass is now gone, having been burned up to accelerate the ship. Now if your fuel is liquid Hydrogen and Oxygen, with an effective exhaust velocity of 4400 m/s, not 2500 m/s, you do a lot better. Its exhaust velocity is 76% higher, so all those ratios we spoke of in terms of fuel to spaceship occur at 76% higher speeds. But if we wanted something with a fuel to ship and payload ratio of our first example, 10 tons of ship and one of fuel, more like a car, we’d need an exhaust velocity 100 times faster than the shuttle booster had, 250,000 meters per second, which is very fast but still just under 0.1% of light speed, and such a fuel would also allow a spaceship to reach Alpha Centauri in about a thousand years, so hardly a miraculous interstellar fuel. So that’s the problem with the rocket equation, or part of it, because I’ve been saying effective exhaust velocity a lot, not just exhaust velocity, and a critical aspect of rocket propellants is that things don’t just magically blow out the back of a ship at thousands of meters per second, and when total thrust matters more than exhaust velocity, like trying to get out of deep gravity well, how quickly you can push propellant out the back can be more important than how quick those individual particles are going, and is a major reason why we often use very different fuels and rockets for the first stage of a rocket launch. We’ve got to burn stuff to make it very hot so that the particles are moving very fast, and that means making our propellant out of stuff that burns, which generally means oxygen, which is a horrible propellant. That oxygen, the oxidizer, is providing all the energy when it combines with the fuel to make the propellant, but it’s essentially sapping our total thrust. Hydrogen is typically your ideal propellant because it’s a single proton and the typical speed particles move at a given temperature goes with the square root of temperature and the inverse square root of particle mass. Quadruple the temperature, double the speed, Quadruple the mass, half the speed. Oxygen, being 8 protons and 8 neutrons, weighs about 16 times what hydrogen does and so is only moving at a quarter the speed of any hydrogen atom at the same temperature. We just saw what a big deal exhaust velocity was for ships, and quadrupling the exhaust velocity of that propellant is the difference between a ton of fuel getting 5 kilograms away from Earth or about 60 times that. It’s a very big deal. We have one more problem though, because we can’t just quadruple the temperature for instance, or we’d melt our engine. This is essentially why the ion drive is so enticing as an alternative, its shoot particles out at very high speed using a magnet and electricity to do so. This is also why we like using light or lasers for a propellant, the exhaust velocity of light is the speed of light, and when you plug that in as your exhaust velocity, you need to be moving at interstellar speeds before you even need to worry about the rocket equation, as it’s about 100,000 times faster than our typical rocket propellants. Heat is not the only way to move particles, nor does it necessarily require burning stuff on location, but it is what gives us high thrust and that’s important for spaceships leaving Earth. We’ve talked about using light sails or ion drives in deep space before, such as in Interstellar Laser Highways, but it’s not something we can really do down here on Earth because of gravity and air. That air is constantly trying to sap away your speed, which is handy for saving fuel on landing by aerobraking but not for speeding up. You also have to maintain at least 1 gee of thrust to avoid falling down, which will rapidly sap your speed via the method known as Lithobraking. So you need to provide a lot of thrust, not just a high exhaust velocity but a lot of exhaust in a short time. We could bounce a very strong laser off a mirror on the bottom of the ship, same as we consider doing for ships in deep space, but this has some problems. Photons, by themselves, are pretty much raw momentum, they are the perfect propellant, and they get around the rocket equation if you’re firing them from elsewhere because they double up the momentum transfer if they bounce and most importantly, you’re not carrying them around on your ship. If you could, via some sort of perfect mirror box with light inside it or with fuels like antimatter or kugelblitz black holes, you’ve got your perfect launch fuel, mostly. See it takes either 3 [correction] gigawatts a kilogram or 3 terawatts to push 1 ton of ship at 1 gee, just enough to make it hover on Earth, if you’re carrying it as fuel, and half that, 1.5 [correction] gigawatts a kilogram or 1.5 terawatts a ton for if you’re bouncing a beam off the ship. This is a bit of problem, because that is a lot of energy. Just to put that into context, a car weighs around a ton and the best it can do is 0-60 in just over 2 seconds, a little over a gee of thrust and can kick up to several hundred horsepower or around half a megawatt, so they’re pulling a similar acceleration as a 1.5 Gigawatt laser-beam-bounce will pull off using [correction] 3 million times more power, 6 million if we’re just emitting it rather than reflecting. What’s more, lasers are quite hard to keep on target in air, especially when powerful like that, which we discussed in Power Satellites. You’re probably wondering why I call photons the most efficient propellant when that car engine was doing [correction] 3 million times better, particularly considering flooring the engine isn’t terribly fuel efficient either. But that car is getting all its oxygen from outside, and it also isn’t using a propellant. I mean technically the exhaust pipe on a car does produce thrust too but it’s pretty minimal. We discussed how air-breathing engines worked last time in Spaceplanes, but we glossed over the energy issue a bit. If I release a bunch of photons, 3 gigajoules worth for a second, I will have accelerated my one-ton craft so it’s going about [correction] 0.01 m/s faster. If instead I heat up a big chamber of oxygen with that, dumping 3 gigajoules into roughly a ton of air, it will heat up by about 3000 Kelvin, moving around at about 1600 m/s, and if I blast that out the back of that chamber, which we’ll say was a ton itself, that chamber will fly off at nearly a kilometer a second, a hundred times faster than the light beam offered, and if the propellant was hydrogen molecules instead of air, about four times faster. Though in fact it wouldn’t since hydrogen has a way higher heat capacity than air, about 14 times as much, but we’ll ignore that for the moment. Beyond noting that it let’s us add far more heat to hydrogen, and thus energy, at a lower temperature, and thus helps avoid melting our engine. Same energy used, 3 gigajoules, but one got you a hundred times as much speed. The problem is that we had to carry all that gas, whereas the photons, assuming we’re even carrying them rather than receiving them from outside, massed virtually nothing, 34 micrograms. That’s very important when you’re in deep space and have no external source of propellant and want to reach very high speeds, in which case light becomes ideal. Here on Earth though, imagine we just had a big plane with a propeller and solar panel or it’s microwave equivalent, a rectenna, which we could beam energy to and which would then power that propeller. It’s never going to need to land to refuel. It’s just sucking air in the front and out the back, powered by an electric engine getting its juice from elsewhere. We can upgrade that to more of a rocket approach too. We suck air in the front into a chamber and superheat it, this is basically how the ramjet and scramjet designs we discussed in space planes work, and gives them the nickname of a stovepipe. They have no moving parts, and they use their fuel merely to heat air. Needless to say we can do that electrically same as a typical electric space heater. Indeed quite efficiently too, heaters of all types, electric or chemical fuel, are the only machine we know of that is 100% efficient, though that’s a bit of cheater-definition since we measure how inefficient other machines are by how much of the energy gets squandered as heat. The limitations on ramjets and scramjets, in terms of speed, as we discussed in Spaceplanes, is that they run out of fuel to heat that air. A Scramjet with a beamed source of power can keep speeding up as long as it can get enough energy in to offset what it’s losing to drag and can stuff all that air through there at a high enough temperature and rate without melting the thing. I don’t want to imply that’s the easiest of engineering feats. Nor is keeping your beam on target, or pumping enough juice in to achieve this kind of thrust. It’s generally hard to jam more than a megawatt of power into a square meter of something, and you lose a lot to heat, which in this case is fine if you’re using something like a rectenna that’s in the actual chamber of the scramjet, the stovepipe. Especially since all it is then is something super-absorptive to the beaming frequency that turns it right into heat. Your ideal beaming frequency is something that is easily absorbed by that stovepipe but goes through air and other materials with virtually no effect. Your stovepipe probably needs to spin a bit to make sure it’s getting evenly heated by that beam, and done right, it could have enough thermal mass to keep going for a while even if that beam broke contact. Fortunately you are still mere milliseconds of light lag from your power sources so maintaining that lock or re-establishing it is a lot faster and easier than when we discuss power or laser beaming for interplanetary or interstellar ships. The other good news is that once you start getting up above the main atmosphere, your drag starts going down, though of course you are also running low on material to cram into that stovepipe and to provide conventional lift on your wings. Fortunately you’d be moving very fast by then, and as you go up more a lot of what’s available becomes hydrogen rather than oxygen and nitrogen. Ideally this should let you avoid even needing any on board propellant, but if you do need some you’re getting an exhaust velocity out of it equal to whatever temperature you can max out at, and if we were talking something like tungsten’s melting point, 3700 Kelvin, diatomic hydrogen would be coming out at 6800 m/s. In an energy rich society that would likely do power beaming, hydrogen is easy enough to source, what with all those oceans, and you shouldn’t even need to tap that until you’re nearly up to orbital speed anyway, if at all. Once you’re out of the atmosphere and in orbit, you do need that on board propellant, but you don’t need the high thrust anymore, and could switch over to a low thrust option like an ion drive, powered by that energy beam, or even just go the reflection route. It’s very easy for me to imagine personal spaceplanes along these lines in an economy running on either fusion or beamed-in power like we discussed in power satellites. You use classic propellers or turbofans for low speed, switch to the stovepipe scramjet for high speeds, and to ion drive or reflection once in higher orbit for long slow acceleration to interplanetary or interstellar speeds. Of course beaming isn’t limited to photons either, you could send a beam of ionized particles instead, reflected magnetically or captured for use as propellant later. Though that doesn’t work well in an atmosphere. So quite a few engineering challenges but no super-science involved either, what’s the upsides of this approach, beyond what we mentioned? First, it does circumvent the giant personal weapon issue. It’s still a fast device meaning you can crash it into something, but unlike our other high-power sources – atomic fission, bottled light, anti-matter, or black holes, it doesn’t actually contain those itself, it just has its own kinetic energy and thus is way safer for on-planet or low-orbit use. Barring a fusion reactor that is also quite compact and cheap, this is really the only option that would ever permit a personal spaceship. Your neighbor can have one in the garage, no risk of explosions or terrorist applications beyond speeding it up and ramming something, which is not very attractive as an attack method especially since to get power you need that off-site beam and you need precision tracking, so if you deviate dangerously you can be easily targeted and your hypersonic debris is going to mostly burn up before smacking stuff anyway, you won’t be pulling high speed maneuvers anywhere near the ground. So it’s very safe, and it’s also very cheap as a spaceship goes, because that core engine is just a big scramjet cone and stovepipe, probably just raw metal, though it might get pricy with extreme precision machining and expensive alloys. However those are both the kind of thing an economy of scale tackles well, so we could be talking about car prices, something you could probably fit into a large garage and could probably buy without being fabulously wealthy. This will probably never be the most efficient way into space, the Orbital Ring is likely to always dominate that for reasonably fast low-energy ground-to-space options, but for an energy rich society, it’s probably the safest and most personally convenient approach we’ve got. It is to the orbital ring what the car is to the train, less efficient, but way more convenient. And it lets you get where you want, whether to a destination on Earth, in orbit or off to the Moon. Indeed it could be scaled up for interplanetary travel, your own personal space-yacht, though without an onboard power source you do have to stay in places where those beams are available or have a secondary engine to work outside their zone of coverage. A bit like early cell coverage, you’d expect it to grow with time. But it would be ideal for space tourism, which we’ll be talking about in a couple weeks, and you can just take your own personal ship anywhere you want, so long as you stick to the powered paths. You probably would use that approach too for orbital versions, keep a powerful and wide beam running between set mirrors or similar, to create lanes, minimizing the need for tracking and keep the beam on, and also minimize traffic problems too. If everyone owns one, you definitely want some metaphorical roads, or Skyways. So we’ve got our upcoming episodes in a moment including a livestream this weekend and it reminded me of a comment I got after one about it being neat during those to see where I did all my writing at. I know a fair number of writers who can work anywhere in a physical sense, but for me the old rule of thumb about finding your own space to work in is entirely literal, and my office at home is entirely configured around that and it’s the only place I write. Writing is very wide area when it comes to both mediums and styles so that no one’s process or advice is really going to work for everyone, or anyone if you try to mimic a process exactly, but some advice is fairly universal and that’s one of them. There’s an excellent video course by Simon Van Booy, 6 Steps to a Successful Writing Habit, on Skillshare that I have to admit appealed to me in large part because it was such a close match for my own process, but as mentioned there are many different work styles and mediums, and someone used to writing news articles on their laptop on the bus between events is going to be far different then someone writing a novel at a home shared with a noisy roommate or someone writing weekly science videos while trying to fend off his cats. So you if you’re trying to get started writing, it’s a good idea to sample the methods of a lot different people till you find your own, and that’s true of almost any creative work, not just writing. Skillshare has a ton of videos on writing, everything from best methods to how to make an interesting protagonist, and a lot of other instructive or inspirational videos on creative processes like drawing or animating. A Premium Membership gives you unlimited access to over 20,000 high quality classes on must-know topics, so you can improve your skills, unlock new opportunities, and do the work you love. Join the millions of students already learning on Skillshare today with a special offer just for my listeners: Get 2 months of Skillshare for free. To sign up, visit the link in the description and the first 500 visitors get 2 months of unlimited access to over 20,000 classes for free. Act now for this special offer, and start learning today. So as mentioned, in a couple of weeks we’ll be taking a look a space tourism, from the near-term possibilities of orbital hotels to the more fascinating options on the Moon and Beyond. But first, next week we’ll commemorate the Fourth of July, the Day of Barbecuing, by taking a look at synthetic meats and other tasty technologies, from lab grown meat to Mammoth Steaks and Dino-burgers. We also have our End of the Month Livestream Q&A coming up, this Sunday, June 30th, at 4pm Eastern, and I hope you’ll join us there and ask some questions. For alerts when those and other episodes come out, make sure to subscribe to the channel, and if you enjoyed this episode, please like it and share it with others. Until next time, thanks for watching, and have a Great Week! This episode is sponsored by Audible. We often dream of a future in space as a future of prosperity, but what is involved in becoming a Utopia of near-endless energy and resources? Recently we’ve been looking at how we might become an interplanetary species, and that’s focused principally on getting our civilization up and out to space and the worlds beyond, so today we’ll take a look a little closer to home at what’s going on back on Earth while all that is going on in space. What life could be like here, for the vast majority of folks who are not involved in leaving the planet. It seems like a good time to focus on a positive future, and in the nearer term, given that 2020 has been a heck of year, and I’m writing this at the end of August so it’s only two-thirds done. So how in this next century or maybe even in the next few decades, might we manage to become both a Kardashev-1 Civilization and a Post-Scarcity Civilization? For channels regulars, you’re probably already familiar with both those terms, but to review, the Kardashev Scale is a loose measurement of how powerful a civilization is, with a K-1 civilization being one that uses all the power of a planet, a K-2 using all the power of a star, and a K-3 being one that uses all the power of a galaxy. That’s it for the official scale and it doesn’t necessarily imply any particular population or technological level, for instance we could potentially be a K-2 civ using all our Sun’s light, 2 billion times what hits Earth, in even a couple centuries simply because the most basic way to do that, enveloping your Sun in bunch of thin foil mirrors, doesn’t require much technology beyond a robot able to dig up metals on some moon or asteroid, turn them into a foil, and make copies of itself that can do the same. As we’ll discuss more today, that’s not really that sophisticated in terms of robotics & AI, and even something as simple as that can kick a civilization into being post scarcity. For a given value of post-scarcity anyway, the basic definition of post-scarcity as unlimited resources wouldn’t seem possible in a finite universe, so we have to modify the concept a bit to use it in practical discussion and we’ll discuss that modification of definition momentarily. But as a quick sidenote first, the original scale created by astronomer Nikolai Kardashev didn’t extend past 3, galaxy-spanning, but folks often tend to throw the idea of K4 or K5 civilizations around, and indeed we actually had to ban use of the term K10 civilization on our facebook forum just because it got so synonymous with magical super-aliens rather than anything useful for discussion. We just don’t have context for them, other than knowing K9 Civilization would either be man’s best friend or have a bone to pick with us. Too many unknowns, so we’ll be trying to avoid that for discussing our future today, by limiting ourselves just to those technologies that seem very plausible under known science and R&D, though for the curious, when folks ask me for a K4-plus scale, I usually say K4 is galactic supercluster, K5 is Observable Universe, and anything beyond that implies folks with access to beyond the cosmological event horizon or parallel universes or alternate realities. And that’s a good example of a technology that if you had it would bootstrap you right into being a post-scarcity civilization by its nominal standard definition, one with no scarcity of resources at all, as you can plunder the multiverse from your backyard. Inside a finite and closed universe that is not possible, and that does appear to be what we live in, since even if this Universe is infinite, the parts we can reach by travel without faster than light propulsion are not, due to Hubble Expansion. Since post-scarcity of that type seems impossible, rather than having a useless term, we modify it to something apparently possible. Since folks use the term to basically refer to a level of technology where folks are not worried about basic survival anyway, we define post-scarcity in that context; one in which folks have no major anxiety over access to basic needs, because things like food and energy and basic goods and services are so readily abundant that they are like finding some air to breathe or a glass of water to drink, just not something most folks worry about in their daily life. Of course what qualifies as a basic need is debatable, and we usually borrow from Maslow’s Hierarchy of Needs for that, a pyramid that runs from the ground floor of basic physiological needs like food, shelter, and sleep up to the more esoteric ones of personal esteem and enlightenment. The degree to which a civilization is post-scarcity is essentially measured based on how many of those needs are easily met, how easily and abundantly they are met, and how far up the Needs Pyramid they are. And this can be in a lot of different ways too, for instance a cyborg who could punch through a brick wall, walk around on an airless rock, and eat anything including dirt, is quite post-scarcity in terms of many needs whether he’s living in a cheerful utopia or some radiation-scorched wasteland full of violent lunatics. So a civilization could end up as post-scarcity, at least in terms of the bottom tiers of physiological needs, simply by modifying themselves to be way tougher, stronger, or smarter, or all of the above. I usually say the big technologies for pushing us into a post-scarcity existence are better energy availability or better automation though, as if you have either you are in a position to tip into post-scarcity. Indeed, I’d argue we are already very close to it, at least those bottom tiers and in wealthier segments of the world, and a lot of what holds us back is that energy is scarce and so is human manpower to use that energy to make things. The key notion though is that there are a ton of technologies, or even just administrative or cultural changes, that individually or grouped up with some others do offer us at least that first tier of physiological needs as post-scarcity, again that being needs so easily fulfilled that folks don’t have anxiety about getting them. Now I use Maslow’s Hierarchy of Needs strictly because it’s well known, it’s got a lot of revisions and variants and debates about which stuff should be where on it, but it works for our purpose as a general thermometer of how post-scarcity a civilizations is. In that bottom tier of physiological needs, usually given as air, water, food, shelter, clothing, sleep, and so on, we’ve been post-scarcity on air and water for a long time with some exceptions like smog-filled cities or desert lands or places torn up by war and chaos. Again there are exceptions, both for the civilization and for the individual’s lifetime, many a person might have suffered from dehydration at some point, but for most of us these are just not things we worry about. We also don’t worry about the cost of making long-distance phone calls or needing to make a collect call, but folks my age and older do remember times when the distance or duration of a phone call was a big worry and when keeping in touch with friends and relatives in other states or countries could become cost-prohibitive. Of course even a couple centuries before that, having a relative move to a different land meant a good chance you’d never speak to them again, when postal service wasn’t cheap or fast, or even didn’t exist, and when a trip home might be an extravagant luxury you saved up for years to do. Incidentally that would be an example of a Tier 3 Need, feelings of love and belonging, and are also a good example of where technology of sheer abundance, like mass production of power or food, doesn’t help you out much or only indirectly. Your phone can’t love you, at least not very well, but it can keep you in touch with the people who do. Infinite energy or raw materials in of themselves doesn’t make you Tier 3 Post-Scarcity, because that’s all things like friendship and family and romance. Of course the same computers that give us better factories and automation and production also let folks stay in touch over continents or use dating software that helps them sift through the many fishes in the ocean to find the right partner for them, it also makes for shorter less exhausting work days with high prosperity to – in theory at least – spend more time with your loved ones and experience less safety and survival stresses. Note that I say in theory because in spite of us being the most prosperous civilization in human history, there’s pretty good evidence we’re as stressed out or even more stressed out than our ancestors, and plenty of data to suggest that higher personal prosperity has only a fairly loose relationship at best with happiness, stress, or contentment. Just as a reminder in there that there’s no single-solution magical wands in technology to make everything better, unless we’re discussing something like brainwashing or drugging folks to be anxiety free, and we define that as a Post-Discontent Society rather than post-scarcity, though would also include an example of a monk or aesthetic meditating somewhere too. All right, definitions out of the way[a][b][c], let’s talk about the technologies on the radar for getting us there. And when folks ask me why I’m always so optimistic we’ll get there and sooner than later, it is because while any one of these given technologies might elude us, or only be developed in a way that doesn’t offer as much practical benefit as we might hope, it’s the sheer variety of options, any handful of which have the potential to get the job done, that keeps me optimistic about living to see this one day. We’ll start with the power issue. Becoming a K-1 Civilization is another example of tricky definitions, because it means using all the power of an entire planet. And one could argue we already do since the sun keeps the planet warm and fuels not only our crops but the whole ecology. Problem is, that definition would make every civilization that ever existed K-1 Civilizations, so what we really mean is either that much electricity or power under our control or more directly utilized. It is a thing to keep in mind though, right now we tend to think of developed nations as being rather big energy gluttons, the average US citizen consuming about 10,000 Watts on average, but this ignores all the energy feeding our crops. We are quite capable with modern technology of feeding our whole population without needing additional farmland, let alone supplemental lighting for plants, but if you grow enough people you eventually have to start powering lights to shine on those plants in some sort of vertical farming scenario or start growing your food off-world. That’s a lot more than a century off though as even if we quadrupled our numbers this century like we did last century, ending with 6.15 billion in the year 2000, we’d have about 25 billion by 2100, and that’s not really a problem with modern technology, even without deforesting everything, let alone needing to power light bulbs to grow food. Though it would benefit greatly from energy abundance since you could cheaply desalinate water and produce fertilizer and produce megatons of aluminum struts and glass or polycarbonate panels for greenhouses and so on. Energy is what powers our economy so cheaper energy helps everywhere, and needless to say you can get the same benefits by being more efficient with your energy usage, more so too because all the energy you use ends up as heat that you have to get rid of. It’s within our ability to make quarter of a billion square kilometers of aluminum foil up in space, sourced off of the Moon, and just put that all in orbit of Earth bouncing light down on us, doubling the light on Earth, which would make us K1 but only for a little while before we scorched the planet. Obviously being able to double our average energy efficiency would be preferable. We hardly need that much power for now either. The Earth get’s 174 quadrillion watts of power from the Sun, and that’s K-1. So if we were talking raw electricity being produced, that’s 17.4 Trillion times the average US citizen’s power consumption. And if you are growing all your food hydroponically via LED lamps you could potentially grow food for one person on a similar power budget. Incidentally we use about 9% of Earth’s surface area for agriculture of one type or another, so in raw power that’s a bit under 16 quadrillion watts to support just under 8 billion people, or 2 million watts, 2 megawatts per person. Hence efficiency can do a lot of good too, not just brute force energy production, as mentioned you could probably support folks on about 1% of that using LED Lamp lit crops in climate-controlled facilities. See our episode on supporting a trillion people on earth for more discussion of that, but in the short term we don’t need K-1 power levels. For how we can get them anyway, see our episodes on Power Satellites, The Future of Fission, or Fusion Power, and any one of those offers huge gains in power production. I don’t want to focus too much on power as we’ve discussed it before, along with food production, but it is a central concept of Kardashev Civilizations. Again the Kardashev Scale really just refers to power being used, not how efficient, productive, or clever you are with it. Improvements in superconductors, battery storage, or even just how cheap we can produce solar panels or other energy related hardware can any of them, all by themselves, help a lot with the energy needs. So too could something like algae genetically tailored to heavily produce feedstock for biofuels, or other genetically modified food crops. And automation also obviously helps. If you’ve got robots that can do all your tasks for you, you are post-scarcity, but we’re never too interested in entirely automated production chains, just adding in a little more automation here and there to improve production rates or consumption efficiency, and that’s not just the big stuff like tractors and engines but even small stuff like the motion detector light switches that come on and off if people are using a room or the one sorting gizmo that lets a job 10 folks do suddenly be done by 9 instead, or even 1. Never underestimate the effect of the thousand tiny things in the production chains in comparison to the one big tech. I remember when the virus first hit and there were a lot of shutdowns of non-essential jobs, I got asked by a lot of folks what qualified as essential. I said if we’re talking a few weeks, not too much, if we’re talking longer, almost everything. I’m sure everyone remembers the Toilet Paper Shortage of Spring 2020, but it hit a lot of things. Just personally, Sarah and I were planning to make some homemade applesauce as she’d picked up a bushel at a local orchard, and last night had us hunting for mason jars and lids and both being shocked out how many sources were out of stock and what the price was for those who weren’t, and I’d imagine we’ve all been a bit surprised by the stuff suddenly in short supply during the crisis either by an uptick in demand or a drop off in production because it was either deemed non-essential for a while or was particularly hard to operate under health safety measures now in place. This is another way you can get post-scarcity too, and its flexibility of production, an example of which would be improvements in 3D printers in terms of speed, cost, or production sophistication. I just mentioned how we had those various scarcities and we have these amazing manufacturing and distribution capabilities compared to prior generations, but they can be very slow to change over. Even if you can suddenly repurpose a factory to produce some needed widget, that widget might have a thousand different components produced elsewhere at other factories, not all of which can be rapidly retooled to produce more of that component, or the components diverted from other products that use them, or the end-product adapted to use some other item we have in abundance. There are many types of waste and one of those is inventory, keeping whole buildings full of some product in case of a sudden demand or because of some sudden drop in that demand, and food is one of the big ones in that we generally waste 30-40% of it to various losses in harvesting, transport, storage, and at the cooking level. Some products are worse, others much more durable and cheap to store, but an ability to adapt production quickly is another lesser-mentioned technological pathway to being post-scarcity especially since it also implies an ability to rapidly upgrade to new technologies. Right now we often run on old tech simply because the upgrade costs, in terms of both hardware and training, is so high. So too better distribution and cataloguing helps a lot, for the latter so some company can find out that screw #45 might be maxed out on production from a given factory but that screw A-12 is nearly identical and sitting there in some warehouse unused. All sorts of smart software to help identify waste, be it in workflow or even day to day life, be it physical items or just time, energy, and personal stress expended when they needn’t have been, could also do wonders for us. What other minor and non-obvious things can push us toward being post-scarcity? Well again it depends on which types of post-scarcity we mean. The higher Need Tiers often involve education for instance, and smarter workers and smarter inventors & innovators, plus more of them, can obviously help across the board, but consider the value of individual education over large classroom lectures. We all know one-on-one is better for teaching most things, but its cost is prohibitive. We also know part of that is the ability of a good teacher to tailor their efforts to the pupil, and not only might interactive teaching software help with instruction but it might help in analyzing a student to be better at tailoring that instruction. Same thing applies to almost any job or life task of course, and we are making huge improvements in such technology. Forget infinite power, a vastly more educated population will get you post-scarcity pretty quick. Something like radical life extension can make you post-scarcity too, even ignoring that a much longer and healthier life would seem like a goal of a post-scarcity civilization, suddenly having folks in their 90s in the workforce with all the vigor of their youth and all the experience of their lifetime is a massive gain. So too, any of the science fiction technologies, Clarketech as we call them, like anti-gravity or perpetual motion machines or anything that lets you bend or break the laws of thermodynamics is instant post-scarcity. But again we’re limiting ourselves to stuff on the radar. Cheaper and renewable power, cheaper water purification or desalination, cheaper production of any raw materials, any and all minor improvements along the production chain, improvements in the skill or stamina of the workforce, all can take you to post-scarcity, or at least the low tiers of need. How about those higher-tiers? And what is life like in a fully post-scarcity civilization anyway?[d] Well those higher tiers of need focus more on the psychological, the longer term, the deeper or more philosophical aspects of life, and of course the big one for discussion in post-scarcity is fears over a loss of purpose, enough that we did an episode just on that a couple years back. However, one thing we need to keep in mind, especially as we start improving all those technologies for the human condition, things in the realms of psychology or neuroscience, cybernetics or prosthetics, medical gene therapy or alteration, and education, is that people aren’t likely to just be sitting around all day listlessly soaking up the sun in some lounge chair waited on hand and foot by robots in a post-scarcity civilization. And I’m sure we would see that a lot too, might as well enjoy life, but as time rolls on and technology improves that relates to raising kids, the equation might alter. We can picture a post-scarcity civilization as one where everyone is indolent and lazy because they can do whatever they want their whole life but that’s ignoring their formative childhood years where they obviously can not, as those raising them determine what they can do. You probably never have accidental pregnancies anymore and every kid who is born was conceived intentionally by people who probably were aiming for their child to be a good citizen and exceptional.[e][f] In the longer term, with enough technology, that might mean every kid was a star athlete and genius by modern standards and further augmented by interactive education technology that was cramming learning into their head better than the most enthusiastic and skilled teachers could do nowadays even one-on-one full time. They might have improved their knowledge of the mind to the point they could rehabilitate any criminal or fix any addiction or mental issue in an afternoon. A civilization like that, whose kids could probably jump in a time machine to nowadays and get a full ride to any school on an academic and athletic scholarship, and got all the ethics in theirearly childhood too, and didn’t die of old age, doesn’t strike me as one prone to indolent and decadent descent or running some horribly mismanaged and corrupt society. So even that worry that post-scarcity civilization, if reached, might be a poison pill, doesn’t seem very likely. What do they do with their time though? Well, some of them probably do sit around navel-gazing I’m sure, or picking up hobbies you or I would find pointless, and might or might not be, but they need to hit one other piece of the Needs Tier and that’s things like self-esteem and peer respect. Those are hard to satisfy with sheer abundance, indeed maybe harder to satisfy, as no one is particularly impressed you can kill a deer to feed the tribe or kill a wolf to protect the tribe anymore, or its modern equivalents. To some degree you have the advantage of the internet, which lets you find that small number of folks who share your obscure hobbies and interests, but we also have grand efforts and wonders, like building all those megastructures we talk about on the show or heading off to space to conquer and tame and terraform new worlds. I get asked sometimes how we’ll come up with all the colonists for space, and I don’t think even now we’d ever have a shortage of volunteers, but folks often wonder if a post-scarcity civilization would find even fewer volunteers simply from losing out on all the luxuries and security they were used to. Quite to the contrary, they probably wouldn’t have to do without those much anyway, but if you have a civilization that’s full of folks who technology and techniques have made nearly superhuman, I suspect most might find the challenge of the frontier quite to their tastes. And we’ll look at some more of those challenges as we continue our Becoming an Interplanetary species series. But as for becoming a Kardashev-1 Post-Scarcity Civilization, it won’t happen tomorrow but I firmly believe we’ll get the capacity for it fairly soon, maybe a generation, maybe a century, but I don’t see it being longer. Hard roads still ahead to get there to be sure, but sometimes the journey is as good as the destination, at least it gives us a purpose, and a pretty awesome one at that. We were talking about Clarketech earlier, technologies so far up the ladder that they are indistinguishable from magic to us, and how any of those sorts of supertechnologies might elevate us to Post-Scarcity all on its own, and it reminded me that it is very hard to find examples of Post-Scarcity Utopias in fiction. Even when we do see them they tend to be intrinsically flawed or hiding over a dark side. Now that is because its fiction and genuine Utopias make for very boring stories, but I think it often paints a more pessimistic view of future civilization in much the same way just hearing bad news all day long can make you feel like the world is coming unglued even when many things are going well. Not every author paints bleak pictures though, and Arthur C. Clarke, famous for novels like 2001, Rendezvous with Rama, and Childhood’s End, and for whom we name the term “Clarketech†was one of the great scifi writers of the 20th century and one who often painted a more hopeful image of the future. His novel Childhood’s End, which was his first novel, is one where we see humanity encounter a peaceful and benevolent alien species who brings on a golden age for us, and is one of his most celebrated works that has inspired so many other stories down the years, so this month’s Audible Audiobook of the Month goes to Arthur C. Clarke’s “Childhood’s End†You can find that audiobook, along with the rest of Arthur C. Clarke’s many excellent novels and short stories, over at Audible. They also have podcasts, guided-wellness programs, theatrical performances, and exclusive audible originals, indeed they have over three centuries worth of audio if you just hit the play button and ran it through every title. If you want access to that massive collection of great audiobooks, like “Childhood’s Endâ€, you can join Audible for a 30-day free trial, and Audible members not only get discounts on any audiobooks they buy, but a free book every month. Additionally, they are now giving unlimited access to their audible originals. You can start listening today with a 30-day Audible free trial. Just visit the link in the episode description, Audible.com/Isaac, or text “Isaac†to 500-500. So we’re into November now and we’ve got a full schedule. Next week we’ll be looking at the concept of Interstellar Trade, then next Sunday we have a Bonus episode coming up on the Fermi Paradox and the Prime Directive, the notion that aliens might be out there but don't contact us because they have rules against it. Then we’ll be taking a look at Asteroid Mining, Orbital Settlements, and Life as a Space Colonist. If you want alerts when those and other episodes come out, make sure to subscribe to the channel, and if you’d like to help support future episodes, you can donate to us on Patreon, or our website, IsaacArthur.net, which are linked in the episode description below, along with all of our various social media forums where you can get updates and chat with others about the concepts in the episodes and many other futuristic ideas. Until next time, thanks for watching, and have a great week! [a]It took a while. [b]too be fair, that's fairly par for the course for me :) [c]No problem, I had my drink and a snack. :) [d]Shouldn't this have been establishd earlier in the discussion? [e]...but without any real effort their own parts. [f]That might be the weird thing, and I hesitate to bring it up, but many folks might be entirely qualified and enthusiastic parents and still lean on the machines because they feel they'd do a better job and don't like to interfere with the 'expert' This video is sponsored by CuriosityStream. Get access to my streaming video service, Nebula, when you sign up for CuriosityStream using the link in the description. The Hitchhiker’s Guide To The Galaxy tells us that a man must walk down 42 roads to be called a man. But that seems like a lot of work for a rather modest reward. The National Space Society tells us there are only 31 milestones to hit to become an interplanetary species! Becoming an interplanetary species, and eventually an interstellar one, is not something that is going to happen overnight. Indeed, even discussing it isn’t going to take just one episode, so we’ll be doing more than one, starting today with our opening moves. It is important to realize though that this won't happen overnight. Even if we get cheap space travel tomorrow it will be centuries before more than a small fraction of our population lives off Earth. I thought today we’d look at some of the critical steps we’d expect to need to make along the way and what it might look like as we head out to space and make it our home. We’ll be borrowing a fair amount from the National Space Society’s Roadmap to the Stars, the most recent edition of which I’ve linked in the episode description. The Roadmap has 31 Milestones and is a concise but detailed and easy-to-understand look at this topic I’d encourage you to explore. Today we’ll be looking at the first 12 Milestones. We’ll also be referencing many of our prior episodes, particularly the Upward Bound series and Outward Bound series, which have tended to focus on specific topics like devices for getting into orbit or how we’d colonize a specific planet. You can see those episodes for specifics and I’ll mention them and put them up on the screen as we go. As something of a side note, as usual I’m writing this episode sometime before it will air, and in this case at the end of May when I was originally going to be down in Dallas at the International Space Development Conference giving a talk and accepting an award from the NSS, which had to be postponed for the Virus, and at the same time we had a rather historic launch from SpaceX, the first private launch of humans into orbit. So, it seemed a doubly appropriate time to be looking at this topic. If anything could be said to have dogged space exploration and settlement in recent decades, it is the seeming halt to it and the absence of private companies in it. We had the Space Race and the Apollo Missions in the 60s and early 70s, landing folks on the moon 6 times, then 50 years of no one repeating that. There are a lot of folks who think it never happened and, in some ways, it’s hard to mock them for that because the most obvious rebuttal is “If this was so easy we could do it 6 times 50 years ago, why haven’t we done it since? And why hasn’t anyone else?†The rebuttal to that is basically that now any further manned missions to the Moon wouldn’t be worth the cost and risk. Which for a lot of folks amounts to saying “So it's basically a big worthless rockâ€. For that not to be true, we need to be able to go back to the Moon in a big and permanent and profitable way and that requires a lot of groundwork which we’ll examine today. Same the Space Shuttle era came to an end and was often seen as far more expensive than it was originally expected to be or was worth, and even though the International Space Station has been running for a couple decades now, we’ve no hard plans for upgrade or replacement and no countries frantically waving their hands asking to donate more money to it. Many like the idea of humanity somehow doing away with money like on Star Trek and just exploring space for the advancement of science and the betterment of our species. But on the Earth, in the here and now, a good way to jumpstart our ascent into space is to make space profitable, so private companies are charging ahead trying to get involved. Eventually, hopefully, space will be the domain of not just big corporations but even small businesses and mom-and-pop operations. You’re not an interplanetary species until most of your people and business is off-world, and that’s why SpaceX tends to be so popular with a lot of us, because not only have they pushed orbital launch costs down quite a lot, the NSS’s Roadmaps Milestone 1, but also made a big step toward their Milestone 4, Establishing in-Space Commerce by Private Companies. Milestones 1-4 might be considered our baby steps, those are respectively lowering launch costs, having continuous occupancy of low-earth orbit, getting space tourism going, and establishing in-space private commerce. Those are continuous goals though, your first step but also something you keep pushing at and expanding. That first milestone, cheaper launches, is clearly needed, but there are many ways to address it, and we looked at some more grandiose options in our Upward Bound series, everything from Reusable Rockets to Space Elevators, Skyhooks, Mass Drivers, Orbital Rings, Launch Loops, and more. Some, like reusable rockets, are approaches we’re already using and improving, while others, like the space elevator, rely on our someday developing mass production of a material able to handle the huge material stresses a space elevator needs. But space elevators could work today with available materials in places with weaker gravity, like the moon or smallest planets. So too, devices like Mass Drivers might be good for Earth but definitely work great on the Moon. Still other approaches like the Orbital Ring, while probably needing a lot of prototyping and offering some technical challenges, mostly aren’t in use right now not because they are hard to make but because they are major investments and will only save us money when we have vastly more space traffic. It’s like building a railroad across a continent, saves tons of money but not until you’ve already gotten very developed, prior to that it makes more sense to use something smaller and self-contained. It’s your freight train to orbit, not your wagon, and it’s something we’d not expect to see until we had that major demand. Such things are not our focus for today, as we look at early space development. These earlier milestones are mostly focused on the technical challenge of getting into space and the basic appeal to people and businesses to be up there. But they’re all focused on Low Earth Orbit, a space just a few hundred kilometers overhead, not the few hundred thousand to the Moon or the few hundred million to the Asteroid Belt or most other planets, let alone the many trillions of kilometers to even the nearest stars. One could argue these aren’t even in space. That the various low-Earth satellites and stations are just orbiting in our uppermost atmosphere, where the air thins out just enough not to drag the satellites down after a few hundred orbits. We would put almost all those low-earth objects even lower if we could and I would not be surprised if we eventually did. Many of our scenarios for much cheaper orbital launch might permit spacecraft that didn’t need to be refueled to maintain orbit by taking in air in to use as propellant and using sunlight as a power supply for shooting that propellant back out. Fundamentally Low Orbit is not about getting into space, it’s just getting out of Earth’s atmosphere and the air drag cost to staying in it. Getting stations higher up is another milestone. But we use low orbit as a testing ground because there are some things we need to test out. How well people do in low-gravity is one of them – we honestly have no idea what the health effects of low-gravity are because only 12 men have ever experienced it and that only for a few days on the Moon. It might be that humans can live perfectly well in the Moon’s gravity, and if not there maybe Mars. Until we check that we don’t know and the answer will matter a lot to our future in space. If the answer is no, that we can’t live healthy for long times on place with low gravity, then we’ll probably never terraform those places and never settle them beyond short term workers in outposts, with everything else being done from orbit of a given body in rotating space habitats, and indeed probably a lot of the work being done by remote controlled robots. Alternatively we might be able to genetically or cybernetically alter people to live in those conditions anyway, though we might have to broaden the meaning of ‘species’ to discuss humanity’s future as an interplanetary species at that point. So one of our big things to test out in low orbit is low gravity, by creating rotating space stations with equivalent gravity to the Moon or Mars. The other thing to be worked out is sustainability. It is expensive to bring food and air and water in, so we need to make it and recycle it and not lose much in the process. If the launch costs were cheap enough, we could constantly resupply our off-world bases. On the other hand, if launch costs remain high, very good automation lets us circumvent that issue by launching just a handful of small robots to the Moon to exploit it for resources. They build more of themselves and other manufacturing assets – either entirely automated or remote controlled from Earth – and we only bring up people, as many as we can but if that got prohibitive we could always grow our presence in space the alternative way of colonizing, by having kids as opposed to mass immigration. That’s likely to be the approach we’d have to take with interstellar travel regardless of whether we get cheap interplanetary travel or orbital launch. One of the more attractive-looking options for getting private investment far from Earth is Asteroid Mining for precious metals. That often tends to conjure a Wild West image of prospectors on jury-rigged spaceships wandering lonely through the rocks in the Belt, avoiding pirates, claim jumpers, and taxmen. Right now, we’ve no clear system for permitting anyone – if they found a bunch of gold on some asteroid – to actually mine it and sell it back here. Right now, nobody has a way to stake a claim to a crater on the Moon or Mars and build a domed farm or mining and refining operation there. Without those, without some way of ensuring they can keep what they invest and make, nobody is going to want to develop in space. But that raises the question of who is offering those assurances and guarantees. Who rules space? Two of the more obvious options are a united Earth Government – like the UN or something more sovereign – or no Earth rule at all, individual governments at this or that world with its own sovereign government. It tends to strike me as more likely that we would probably only see new sovereign states appearing in space in three cases: First, that they had grown in number so much that they rivaled terrestrial nations. Second, that they were so far away that being part of an Earth-based nation simply wasn’t practical, like interstellar colonies or anything out in the Oort Cloud where even routine communications would take months or years. And third, where some more powerful nation was essentially sponsoring them, as has happened often in history where some nation wanted to spite a rival by supporting the independence of some place they controlled or didn’t think they were in a good position to make a territorial claim on some place but felt they could more easily sponsor them as a sovereign and friendly state. This last route seems the most likely to produce new nations in space first. Some outposts of tens of thousands currently beholden to this or that nation or parallel entity have started resenting their administration and rival powers lean on that entity to let it be free to run its own affairs. I suspect you would first see them obtaining sub-division status. In the US for instance we have the federal government, then beneath that the states and territories, and beneath that more sub-divisions like counties, townships, cities, villages, and so on. A colony of ten thousand people is not going to be taken seriously as a new nation, partially because it just lacks the capacity to support a lot of critical government functions. While big organizations can often be rather slow and bureaucratic, they do tend to provide big advantages to their members. It’s hard to have due process and an appeals court for instance in a nation of ten thousand, where there’s probably only a dozen lawyers, hard to have a university with lots of professors in wide ranges of specialties, and so on. You could farm that out to others, like sign a treaty with a terrestrial nation to handle your high crimes and appeals or send your students to and so on, or even to be your big gun for diplomatic and military intervention when needed, and potentially not the same country for all these functions, and we’ll explore these ideas more next month in Future Types of Government. In the short term, you need legal and political protections for those going into space, and you probably need some sort of land grants or other economic incentives to encourage folks to head out there, Milestone 8. Once they are there, to be safer, to feel safer, and to operate cheaper, you need to improve your technologies for self-sufficiency, Milestone 9. This doesn’t have to be total self-sufficiency of course, only interstellar colonies would need that and even they could be relying on trade of information from back home, getting tech updates and so on. However, they do need to be self-sufficient in the sense of not running at a deficit. If a colony on this asteroid doesn’t grow much food, then it needs to be able to produce something to trade for it and at a rate sufficient to get what they need. There’s always a cost to trade so ideally they should be mostly self-sufficient, especially on food, air, water, and energy, the four things you need constantly to keep your colony running. Those are your big jugular weaknesses, and the degree of self-sufficiency is obviously a lot different for a space hotel in low orbit and a distant sub-surface rotating habitat in a Kuiper Belt Object far from the Sun. Fundamentally the same concept though, you need to make sure your total imports are less than or equal to your exports, and reliably so, which is often going to mean minimizing what you need to import, and often maximizing the quantity and variety of things you can produce locally. That’s a pretty big aspect of Milestone 10, which is multi-generational survival off Earth. If you’re not stable, if you are essentially running in deficit, you won’t last. But more importantly we’re not even talking about humans here, we don’t know how most animals will fare in terms of being born in low gravity or inside relatively primitive artificial ecosystems. Some will likely handle it better than others but in some cases we might need entirely artificial ecosystems of very large and diverse natures. During this early phase we can be sending folks off to Mars to explore, or off to the Belt to find precious metals, or set up this or that trial method at fuel or food or air or water production. But anything truly grand up in space requires first tackling how we can establish reasonably closed ecosystems up there, and how humans themselves handle protracted periods in space, both physiologically and psychologically. Not just as adults, not just trained astronauts picked from the best of the best, but how you raise a kid there. How you keep them educated, fed, comforted, and employed… and also how you keep them safe. Milestone 11 is developing reliable defenses against asteroids hitting Earth. There are some nearer-term related concerns we’ll have to address along the way. For instance, our atmosphere protects Earth from small meteors and space debris, but stations and ships will need their own protection from these common hazards of higher orbit. And whatever technologies we use to adjust asteroids trajectories away from Earth could also be used maliciously to send them to Earth or to other targets. With unpredictable humans as part of the landscape, space will need to be watched for hazards more closely. As we start in-space fabrication of larger structures, milestone 12, this is a greater concern, more things to be hit, more things to shoot out debris to hit other things, more things potentially losing parts or trash in construction, maintenance, or operation. More places for rogue or malicious elements to hide out or exploit. But if we can conquer all of these issues, make it to these milestones, we’ll still be long short of becoming an interplanetary species, but the Egg that is Earth will finally have hatched, and we can look onward to the Moon and other planets and seeing a decent fraction of the human population begin moving into space, our mid-game, and we’ll explore that more in the next episode. So what does a civilization at this point look like? At this stage we’re probably not at the point where anyone can fly to space as easily as flying to another continent, or even necessarily to point where it’s parallel to first-class accommodations on a luxury ocean cruise ship, but there would be folks working in space and folks traveling there who were not either ultra-rich or government-funded astronauts. We would be expecting thousands of people to be going to space every year, possibly every week, and many for recreation or for jobs that had nothing directly to do with science. We would be seeing some legal framework being placed for nations, companies, and individuals to stake claims to territory off Earth or other limited resources like a band of orbital space around Earth they leased. And we would be seeing more and more of the daily needs of those in space, like air, water, and food - not to mention gravity - being supplied on sight by recycling and limiting waste, with an eye toward long term sustainability and self-sufficiency. We would be seeing the groundwork in place for detection and protection from asteroids, meteors, and artificial space debris getting set up along with the personnel and government apparatus for tending to that. We would be seeing the beginning of orbital industry, production, and fabrication, to build what we need for space in space. That’s the future we’re reaching for in part one of our journey to becoming an interplanetary species, and it’s a place we could reach within a couple generations of now, and which I believe most of us will live to see. The beginning of a bright and bold future out in space. Throughout today’s episode we looked at the first 12 milestones on the Roadmap, and some of those milestones are ones we’ve looked at in depth before but one we’ve not done in spite of many requests for it was on Asteroid Defense, and it was long overdue and is out now on Nebula, where we’ll discuss the realistic scenarios for an asteroid impact and what technologies and approaches are on the table for dealing with it. Nebula, our subscription streaming service, was made as a way for education-focused independent creators to try out new content that might not work too well on Youtube, where algorithms might not be too kind to some topics or demonetize certain ones entirely, or just doesn’t fit our usual content. And if you’d like to get free access to it, it does come as a free bonus with a subscription to Curiositystream, which also has thousands of amazing documentaries you can watch, on top of the Nebula-exclusive content from myself, like our Nebula-Exclusive series, Coexistence with Aliens, and many other excellent works by creators like CGP Grey, Minute Physics, and Real Science. If you’re a curious person, Curiositystream is now just $14.99, a 26% Discount, and it gets you access to thousands of documentaries, as well as complimentary access to Nebula for as long as you're a subscriber, and use the link in this episode’s description. Last week we looked at some truly enormous space habitats we might build in our future as an alternative to settling new planets and next we will take a look at how we can go about acquiring the vast amounts of raw materials we’ll need to construct millions of those continent sized habitats, and ask if we should dismantle the solar system itself to provide them. After that we’ll be back to the Fermi Paradox series to consider disappearing stars and cosmic voids, to consider if such things are natural or might be signs of older alien civilizations dismantling their own solar systems or even entire galaxies. If you want alerts when those and other episodes come out, make sure to subscribe to the channel, and if you’d like to help support future episodes, you can donate to us on Patreon, or our website, IsaacArthur.net, which are linked in the episode description below, along with all of our various social media forums where you can get updates and chat with others about the concepts in the episodes and many other futuristic ideas. Until next time, thanks for watching, and have a great week! This episode is brought to you by Skillshare As we celebrate one more trip around our star, we can look forward to traveling to many new stars. As we wrap up the year 2020 we are also wrapping up our Becoming an Interplanetary Species Series with this epilogue on Becoming an Interstellar Species. This is tricky for more reasons than just the difficulty of traveling to distant stars and making homes under alien suns, because to become an interstellar species would also imply you were just one species, and that’s part of the problem. Interstellar distances are so immense that even objects which could cross our whole world in a second takes years to get to the nearest star, and our fastest man made object would still need longer than all of recorded history to reach that star. Indeed our galaxy alone is so immense that even signals, let alone spaceships, need as long to cross the galaxy as modern humanity has been around. Even ignoring things like genetic engineering, which might play a big role in humanity settling new worlds, simple exposure to radically more diverse environments than we see on Earth would presumably cause species diversity faster than ships could settle our galaxy even if traveling at a good fraction of light speed, while at the speeds of our fastest modern spacecraft, an effort to colonize the galaxy would take more like a billion years, and a billion years is considerably more time than it took for some common ancestor to diverge into humans, cats, dogs, and dinosaurs. So we’ll be asking how we can make these trips faster, how we can make them economically, and how we can stay unified as a species, or if we even can or should want to. As we move out of 2020 into 2021, we’ll ask how we can visit our first neighboring stars by 2121, and how we can settle the galaxy by 202020, 200,000 years from now. We will obviously need something far better than simple chemical rockets like we use nowadays to achieve that timeline, but we do have the capability to colonize new star systems that way if it came down to it. This is the key notion of what is called a “Generation Shipâ€, something we examined in detail in our Generation Ships Series, and it relies on the notion of essentially building a small mobile planet, akin to the O’Neill Cylinders we discussed as orbital settlements throughout this series. We have nuclear-powered ship designs that while never built do work on very well grounded principals – see our episode the Nuclear Option for details – and which depending on design and hurdles we might encounter when building and deploying them offer travel speeds of around 1% of light speed, possibly a bit slower, maybe a bit faster, but cutting trips to neighboring stars down to centuries rather than tens of millennia. Those same principals could be used to artificially light, heat, and power the generation ship and its people and ecology for the duration of the trip. This is technology we do already have, though again would need prototyping. Another option often considered though is to put people to sleep or in stasis or on ice, and we looked at that scenario in our Sleeper Ships episode and will discuss freezing people, or entire civilizations, in a couple weeks. That is one way you can ensure its modern humans settling every world at least, as they would experience no evolution while frozen for the trip, but the key problem isn’t really a problem, namely that the technologies you need in order to restore people you’ve frozen – and killed – are the same sorts of technologies that permit radical life extension as well as radical automation. If you have little robots that can fix cells damaged by freezing, you have little robots that can fix cells damaged by aging, little robots that can fix machines on your ship, and little robots that can build machines and organisms from blueprints on other worlds. Similarly, if you have genetic engineering to change people to more easily adapt to a world, you have the technology to keep people at their current biology too. Indeed we can already do that. We can make digital copies of DNA, we can print DNA, albeit very slowly, and we can implant a printed strand of DNA into an egg, so our interstellar arks do not need to carry tens of thousands of living copies of a given organism to avoid genetic bottlenecking or even frozen fertilized embryos. If it's important enough to a civilization, even with modern technology we can get humanity to each world we settle with our modern DNA and keep it that way, if the folks on each of those worlds choose to. That strikes me as unlikely, and of course the same DNA or close enough to count as a single species isn’t helping with language and culture drift. This is the origin of our joke on this Show that if we don’t find aliens in the galaxy, all we need to do is wait a little while and they’ll be around every star. Indeed only if we can achieve significant trade between neighboring stars is there any real chance that the folks living in your neighboring system would be any more like you than those clear across the galaxy. We looked at Interstellar Trade recently and it does seem possible, and we have also looked at a variety of ship propulsion concepts ranging from the near term to the really advanced or enormous, everything from using anti-matter or black holes to run ships up to moving entire solar systems or even galaxies. But what is likely to be our first interstellar ship, and when? A few minutes ago I said we’d ask how to get to our neighboring stars by 2121, and if that’s the case, given that the nearest is over 4 light years away, and we have not funded let alone started building an interstellar ship, the most optimistic production timeline would require traveling at 5% of light speed to get a ship there by 2121. This is a velocity that might be reachable by fission fragment or pulsed nuclear propulsion – shooting nukes out the back of the ship to ride the explosion – and should be achievable by a fusion drive if we ever get fusion working. Indeed, given that the joke about fusion development always hinges on it being 20 years off, were that to be true, commercial fusion by 2140, we probably could get a ship built within a decade and then you only need to get to 6% of light speed to reach Proxima Centauri in the 70 years remaining. Fusion is great for interplanetary travel, it makes the whole process vastly cheaper and easier, in truth so does fission though fusion would be better in almost every respect and by a wide margin. A fully developed solar economy is much easier to reach with the nuclear options, but neither truly permits spaceships that can reach the nearest star in a mere generation. At least not directly. We might do much better with light pushing on our spaceships, and the sun is an abundant source of light from its own internal fusion. We often talk on the show about using focused light or lasers to push ships up to high speeds, and for slowing them down too, though that is harder especially in an uncolonized new star system. This offers near-light speed travel though does not help with the interstellar debris and collision issue much, and that requires some explaining. Space is pretty empty, interstellar space even more so, but not so empty you can expect to safely fly several trillion miles or kilometers without encountering something the size of a piece of gravel. In and of itself that pebble is just a pebble, probably containing no more energy than a bullet, but kinetic energy and damage from impacts has to do with relative speeds when colliding and there’s a lot of energy involved in those kinds of speeds we contemplate for interstellar travel. Now I’ve heard people say that even hitting an atom would destroy a ship and that’s hyperbole. We routinely get hit by relativistic atoms – relativistic meaning moving at a decent fraction of light speed. It's not healthy but more in the way radiation isn’t healthy and even fairly thin shielding protects you from that, and the concern is about being hit by trillions of those per person, not one per ship. On the other hand, cosmic dust grains vary in mass a lot, the ones hitting Earth range from 10^-16 to 10^-4 Kilograms, a variation of a trillion fold, and hitting the latter kind would be on an order of a small nuke at near light speeds, while the smaller kind carries less energy than a mundane object we might throw, like a baseball, and those smaller dust grains are vastly more common. Incidentally a dust grain massing 10^-16 kilograms, small as that sounds, still contains billions of atoms. The faster you go the more frequently you collide with objects, or need to detect and avoid or destroy them, and the more energy it takes to reach that speed, such that there is likely to be a natural optimal speed way lower than light speed that ships move at between stars. That may vary based on many factors, including the mission’s purpose and priority, but isn’t likely to be over half light speed and may be as low as 1%. At that speed you have to be hitting rocks bigger than humans could comfortably lift to be getting nuked by the collisions and you have a lot more time to dodge, and much bigger targets to detect and hit if you can’t. But I would guess that it would be collision avoidance and management that represent the real limits on space travel speeds, not energy or fuel, for the future. One thing often ignored in science fiction where faster than light travel is ubiquitous is that every pebble you hit, every dust grain, at those speeds would actually have infinite energy. That’s on top of other issues common with faster than light travel, like having a black hole behind you and a white hole in front, or causing time travel paradoxes just from flipping the engine on, and on generally requiring exotic matter that probably cannot exist in nature. So we have a handful of plausible near term drive methods for interstellar spaceships that won’t take whole historical epochs to visit nearby systems. Fission, Fusion, Micro-Black holes, Anti-Matter, and Focused Light Pushing on Solar Sails, and basically that list is slowest to fastest. The light beaming trick, be it visible light or other spectra, has the speed advantage because it doesn’t require carrying all your fuel, so your speed with it depends on how big a beam you can send, how long you can keep it focused and on target, how much energy your ship can handle without melting, and how well your ship can handle space debris and collision issues. Micro-Black Holes and Antimatter permit much easier ship control and braking if you can do either but both are a lot more high tech and require some big assumptions. See our Episodes on Antimatter Factories or Black Hole Ships for further discussion. Laser propulsion on the other hand we can do right now, it's lower tech than fusion in that regard, since we don’t have controlled fusion. Emphasis on ‘controlled’ though, we have had the ability to do fusion since even before we invented fusion bombs in the 1950s, a hydrogen bomb is a fusion device, and it really is less crazy than it sounds to make a fusion propelled ship driven by hydrogen bombs. Almost all these ships have to be pretty big though, whether they are manned or not. You can make a flyby probe designed to race through a star system at near light speeds that you shoved up to those speeds with a laser, but when we’re talking about stopping the dynamics change a lot. So our first interstellar ship is likely to be an unmanned probe pushed by light, note that I’m not including some of our interplanetary probes that have left our solar system already, they will take tens of thousands of years to get anywhere, will have broken by then, and I’d actually bet they won’t ever arrive at other systems. The final destination of Voyager 1 is probably a museum, someone is likely to pick it up and either bring it home or to some colony, and I’d say there’s a pretty good chance it will be in the Smithsonian before we have an interstellar colony with a museum. Or not, interstellar arks need to be big things, especially if you’re not using various post-biological approaches like growing your colonists on site from databases. Such being the case you probably would have museums on those ships. We often picture those as having thousands of people and a voyage of a century or more, and if you look at towns in that age and population size, like my hometown of Geneva, many do have museums, as mine does for instance. Bit of a tangent but it's worth remembering that these colony ships of the generation ship variety will generally develop pretty complex civilizations onboard even before they actually arrive and found a colony. What’s the fastest way to get a human colony going though? With the technology that is reasonably plausible anyway? We talk a lot about getting giant generation ships to other stars and that tends to be the preference because it works best for modern humans, but if our goal is to get humans established in other solar systems fastest, how could we do it? Two pivotal terms there are “Fastest†and “Humanâ€, and part of why we are talking about becoming an Interplanetary Species. That term human can be real ambiguous and how we define it matters a lot if we’re contemplating fastest methods. More than just for who gets that first colony in and on what date too. In general whatever we do first has better odds of being what we do most. I don’t mean this in a militant sense though, as we’ve discussed before, you can not ‘beat everyone to the punch’ with something like self-replicating spacecraft trying to claim all the cosmos. Any ship you send out has to slow down to colonize, and for ships that have onboard fuel supplies, two identical ones, one meant to slow down and one not meant to reach maximum speed, the latter can move twice as fast. You need to be able to slow down to colonize something, you do not need to slow down to ram something, quite to the contrary you do more damage by speeding up. So anything obeying the rocket equation, whether the fuel is h-bombs, fusion drives, antimatter, or a portable black hole, can be easily detected on launch and caught up to and destroyed by a pursuing craft using the same propulsion design, or several smaller ones. There is no plausible scenario for escape, as every time you light your engines up for a course corrections you become visible again and very much so, and your trajectory is easily calculated. The pursuit ships will always have an edge in maneuverability as well as detectability too, since their drives point away from you but yours points back toward them and toward the homeworld’s detection arrays too. Laser pushing avoids the rocket fuel issue but actually results in you being more detectable, lower in maneuverability, and they can also attack your pushing beams built here at home, or just block them and use that energy instead, such as for pushing their own interceptors after you. Such being the case you can have an interstellar colonization race, but there has to be an element of non-hostility involved because if you try to grab everything for yourself everyone else can dogpile you very easily and wreck your ships, even with years of headstart. There’s also plenty to choose from and divide up too. The nearest star may be over 4 light years away but space is three dimensional, there’s over a thousand stars within a volume ten times wider than that and over a million in an area 100 times wider, and even that is a volume that would barely qualify as a single tiny closet in the great city of the galaxy. So if you try to seize them all, unless you have such an advantage you could conquer our system first anyway, you will lose, and there’s so many out there that there’s no real shortage. Who gets them then is less an issue than how they get them. Folks willing to send their minds by hard drive to be inserted into an android body on the other side can get there faster, for instance. So can an artificial intelligence, though that might be a redundant statement to many people. But this doesn’t mean their civilization is colonizing by sending digital people everywhere, they don’t really need to. You can send the great big generation ships carrying people, regular people, almost as fast as other follow up ships carrying less organic materials. Same top speed for the ship, but generation ships have to accelerate pretty slowly, potentially needing several years to get up to cruising speed and back down, while something with no organic components can probably get to speed in mere days or weeks. For voyages of thousands of light years that means little but to colonize a neighboring system it means a lot. Now the concept of a von Neumann probe, a computer probe that arrives in systems and replicates, is a popular one, but how intelligent it is depends less on your available technology and more on your confidence in it not turning crazy or traitor on you. That can be an AI you’ve rigorously programmed or an uploaded human mind or one heavy on cyborg components and mind augmentation, and we see examples of that in science fiction, such as Dennis E. Taylor’s Bobiverse series or Dust’s Chrysalis. For that first interstellar colony, we need a lot of robotic automation to build the ship and laser pushing system, and we’ll need it on the other end too, so folks are likely to already be fairly comfortable with simple AI. However, again for that first set of colonies I can’t see us trusting an entirely artificial intelligence. On the other hand a digitized human selected for their devotion to the project and reliability, or someone with a lot of modifications to handle large accelerations and oversee robot drones probably will be more acceptable. The key thing is that the fastest way to another system right now is the laser pushing system but there’s nothing to slow you down on the other side, and the best way to slow is to engage in a literal crash project like we looked at in Exodus Fleet, where some vanguard chases forward of your fleet on a sun dive vector with a solar sail, being slowed some by the plummet but using the energy it receives to power a laser beam backwards, which hits another vanguard, who is slowed more, who does it to another and so on until you can actually get a stationary laser array around that sun to slow your fleet. That might work with sub-intelligent AI, it’s not that complex a process, but it works best if it’s being controlled by something intelligent who’s reasonably close, not light months behind. It probably does not require human level intelligence, either way, but might benefit from it. Thing is, this system vanguard controller can be vanguard for a lot of things, because a great big mirror and transmission arrays also is great for getting signals from home, not just slowing incoming spaceships, and it’s also a great power supply for early resource harvesting robots. Regardless of how you colonize, the vanguard is pretty much always going to be a robot with some construction capacity and some intelligence, and probably as little of the latter as needed unless the vanguard is actually an intelligence, or intelligences, we’d classify as regular old colonists. If your civilization considers a human level AI a person, then sending one as your vanguard probe is not sending an unmanned probe, just one lacking biology. From there they can slow incoming ark ships down, whether they’re generation ships or carrying frozen people. Or they could be receiving ships full of harddrives with intelligence on them or building big dishes for receiving transmitted minds, the former process is slower but maybe much cheaper and safer. Or they might be 3D printing equipment, including basic biology. We more or less have the technology to clone humans and raise them in vats, or bags, in modern times, we don’t do it though for ethical concerns so it's hard to say what sort of challenges growing a bunch of colonists in tanks might have, but it should be doable too. It might be easier to do this from entirely frozen samples of human biological material, same for other flora and fauna, but we can print DNA and a basic human cell, or other cell, isn’t beyond the bounds of doable either especially given that you already have self-replicating machines to be even contemplating this as a colonization method. The upside is that you can pretty much pick your methods because none has a vast advantage over the others. A generation ship kilometers wide and long might seem far harder than a tiny shuttle containing harddrives and self-replicating robots but the key component there was ‘self-replicating robots’. If you are launching a lot of robots to systems to arrive and replicate more of themselves to build your colony, then send out copies to other systems, you can just easily make the first stop some uninhabited asteroid in your own system and have it build a big ship. It will take vastly more energy to get it moving and stopped at the other side but it’s a one time investment either way, and an uninhabited star system has tons of energy being wasted already, so it only matters if you’re short of it in your home system. And of course you’re not in early colonization periods since you can just tell those little robots to build power collectors, you're many millennia away from having enough people in your home system to be worried about power consumption by spaceships, as we looked at recently in Interstellar Trade. In such a scenario though, whether it is in the year 2121 or the years 3131, your interstellar ships are arriving at new systems after your own home star systems has started down the path to being a Kardashev-2 Civilization, working to being a Dyson Swarm, because that exact same technology for colonizing those systems lets you mass produce cheap solar collectors here too and you’d want them for sending out your ships initially. See last week’s episode on Kardashev-2 Civilizations for more discussion of that notion, but the critical idea is that you are already on your way to being a K-2 civilization here before your first colony ships arrive. And there is no reason that couldn’t happen in the next century. It's weird to think things might move that fast, especially after all the long delays getting to Mars or even setting up a Moon Base, fifty years and counting since we first traveled to the Moon and not much less since we last went there, but that is often the nature of growth and expansion. Once the tipping point is hit, the avalanche begins, before that you crawl. I don’t think we will have our first interstellar colony founded by 2121, but we well might have ships headed out by then, and the weird thing is that it's not much harder to send those ships out than to colonize any of the planets in our own solar system, plus as soon as we do have those moon and asteroid bases and orbital settlements, we have all the ingredients needed for interstellar travel. All those automated constructors, power satellites and mirrors, and giant orbital settlements are easily modified and repurposed to create our interstellar infrastructure. In many ways, the jump from an Interplanetary Species to an Interstellar One is far shorter than our jump to becoming an Interplanetary Species. So Becoming an Interstellar Species will likely follow on within the same century we become an Interplanetary one. At least the launch will, there’s no getting around the timelines. Whether you can only get those ships up to a few percent of light speed or to within a few percent of light speed is the difference between colonizing our galaxy in a couple hundred thousand years or several million, but it still requires timelines beyond any prior human endeavor. When you consider though that there are hundreds of billions of star systems out there, we are likely to be colonizing hundreds if not hundreds of thousands every single year once we get rolling. It is very likely we could send colony ships out at half of light speed or better, especially if most of those ships were originating from this solar system and making the lion’s share of the journey through regions of space already colonized and with the travel infrastructure in place. In that case we may well have managed to settle every single star in the galaxy by 202020, two hundred thousand years from now. That just leaves the question of if it is worth doing and if most people will think it is. One key point to understand is that it doesn’t require any sort of unity or consensus, anymore than early human tribes spreading around our planet did. So in that regard it doesn’t matter if most people’s answer to the question of if we should colonize other worlds is indifference. As technology improves it gets easier and easier to do so and requires less agreement and less hardship to the civilization to invest in the effort. But it is an investment, the gains of becoming an Interplanetary Species are huge and local, those on Earth will directly benefit from it enormously, and migration around the solar system will be relatively easy. This is less so for interstellar travel but as we discussed today, that next jump is less difficult, if far more time consuming overall. 2020 has been a rough year, and not one that encourages us to look to the stars with optimism, but victory is far closer to hand than most would think, and if there’s one thing this year has proven, it’s that we’re a tough species and we don’t give up easily. They say that “the Sky is the Limitâ€, but it doesn’t have to be, indeed it’s just the gateway to limitless opportunities. Happy New Year! So that wraps us up for 2020 but we have 2021 just ahead and we’ll get to our upcoming schedule along with some end year announcements and thoughts in just a moment. First, though, one thing 2020 has shown us all is the importance of being able to function online, and that’s everything from socializing to working and learning. It’s also taught us the importance of flexibility, and a good contingency plan you can have in place is to have a hobby or two you can enjoy that might be a way to earn money. We talk a lot about the future of humanity here, but we all have our own individual futures and one way to be a lot more secure and happy in yours is to have some hobbies you enjoy that can potentially be turned into your new career or business. A lot of folks are busy making their New Year’s resolutions up and one I’d strongly advise is to choose to find some hobby you think you would enjoy that could also serve as that fallback job, side income, or dream business of working for yourself at something you love, which I can testify to as a dream well worth pursuing. If you’re looking for a place to find hobbies that have potential financial rewards, our partners over at Skillshare have an amazing collection of them on many topics and at many skills levels, but I would suggest trying out Emma Gannon’s “Discovering Success: 7 Exercises to Uncover your Purpose, Passion & Path†as a way to help you see what interests and talents you might already have that might become your hobby that leads to your dream job. Perhaps you’re trying to adjust to working in a new environment or just looking to pick up some new skill or hobby, Skillshare has a course for it, whether you’re a beginner, a pro, a dabler, or a master, Skillshare has thousands of classes on a wide variety of topics from experts to help you learn. Skillshare is an online learning community for creatives, where millions come together to take the next step in their creative journey, and Members get unlimited access to thousands of inspiring classes, with hands-on projects and feedback from a community of millions. If you’d like to give it a try the first 1,000 people to click the link in my episode description will get a free trial of Skillshare premium so you can explore your creativity. Act now, and start learning, today. So 2020 has been quite a year, for good and ill, and most of us will be glad to see the backside of it. I tend to feel a little guilty at what a good year it’s been for me myself. I mentioned dream jobs earlier and 2020 has continued to let me do mine, our show has continued to grow and for those of you who joined us this year, thank you for coming on board and I hope you’ll enjoy 2021 too. In recent years I’ve tended to write the episodes 2-3 months out, except for the sponsor reads and schedule at the ends of episode, which I usually do a week before they air, so I’m busy drafting our March 11 episode, Killing Stars, as I write and record our schedule here on December 21st for our December 31st episode. It’s my habit to show the next 2-5 episodes on the schedule at the end of each episode, but if you’re curious there is a spreadsheet I do the full schedule on a few months out and keep a chronological list of episodes and links to them in, though episodes more than a month out are tentative for air date even when already written, and I will attach a link for that in the episode’s description if you want to see the full roster of what’s planned for next year or go see what you might have missed from previous years. As I mentioned it’s been a good year for me, the show has done well and I got married, but one word of advice I’d offer folks is that an awful lot of how your year goes is about how you choose to look at it, glass half empty, glass half full, or “yum, I just drank a tasty drink and still have half of it leftâ€, or maybe even, “Hey, I have a cool new drink I can recommend to friends who might enjoy it and could use something to improve their moodâ€. Cheering other folks up is often good way to cheer yourself up. I feel like in the long term 2020 will be a net positive for humanity, challenge often brings innovations and solutions and helps sweep away stagnation, but rising to challenges is its own reward a lot too. I ended todays’ episode with the reminder that the Sky isn’t the Limit, and I think that’s a good note to end the year on too, with the reminder that challenges make us stronger and better, so that the journey is often as important as the destination. I often get asked how I can stay so upbeat about my life, the future, and about humanity in general, and I would say it helps when you can think of those challenges as benefits. I wouldn’t say we should be glad for hardship and view it as a gift, that might border on masochism, but taking time to think about past or current hardships and how they had silver linings, like giving you a new skill or bringing you closer to a friend you went through the crisis with, does help you stay upbeat, and it is almost always easier to get through life with that mindset and attitude, even if just because your stress levels are lower and folks tend to enjoy your company more. Hopefully watching this show and what we see for the future helps you do that too. Speaking of the show and the future, this may be the end of the year but we’re still here every Thursday Morning, and will be again this Thursday, January 7, to look at earlier times and civilizations, indeed the earliest possible times and civilizations, as we take a look at Civilizations at the Beginning of Time. The week after that we will be looking at civilizations even colder than ours is this winter, in Cryonics: Frozen Civilizations. For Alerts when those and other episodes come out, make sure to subscribe to our channel here on youtube or the audio-only versions available on iTunes, Spotify, and Soundcloud. And if you would like to help support future episodes, you can donate to us or become a sponsor for the show on Patreon. All those options, along with our social media forums on facebook, reddit, discord, twitter, and our website are linked in the episode description. Until Next Year, thanks for Watching, and have a Happy New Year! This episode is brought to you by Skillshare. Science fiction has taught us to be skeptical if aliens claim, ‘we come in peace’. But what if they actually meant it? Quite a few tales in science fiction and theories among UFO watchers involve rather sinister aliens, or those that appear nice but are not as benevolent as they seem, but occasionally we do get examples where those aliens really are nice and enlightened folks. I suspect their relative rarity tends to come from them being a bit boring from a story writing perspective, no conflict or conspiracy, no fun. I thought we would ask ourselves what a benevolent group of aliens would be like, what they probably would not be like, and what we might be like to other civilizations if we got to be nicer people and encountered some fledgling alien civilization ourselves. We must start though by acknowledging the obvious, benevolent is a bit of a subjective term, to say the least. As we discussed in “The Fermi Paradox: Zoo Hypothesisâ€, an alien race might think they were doing us a favor by keeping us tucked away from interference by others and ignorant of their existence. Indeed as we noted there, a post-biological race might flat out kill us all for our own good, simply because they thought we’d be a lot safer if they came in, scanned our brains, turned us off in real life, and rebooted us in some nice safe simulated reality somewhere and time. That would be an example of where a civilization with high-minded intent literally committed genocide, from a certain point of view, and it’s not the only one. You might see some fledgling species as so innately dangerous to the wider galaxy that you felt obliged to wipe them out. Though you might instead alter them so they were not a potential threat, like making them less aggressive, and depending on how they did that, and again, from a certain point of view, it might be effectively wiping out a civilization. Many would view the wholesale alteration of a person, so they acted very differently, against their will or without their informed consent, to be a type of death and maybe a fate worse than death. But much like brainwashing people versus raising children, the line can be rather murky. However, this is a pretty common thread in science fiction with more enlightened aliens. They either try to help us achieve enlightenment or refuse to help us or have any dealings with us until we evolve to be more enlightened. Or grow to be more enlightened anyway. Science fiction writers have a bad habit of using the word ‘evolve’ to describe non-natural developments, when an ancient and powerful race or entity showing up to change and improve your species would be more appropriately called Intelligent Design. Personally I don’t subscribe to the non-interference policy advocated in Star Trek and its Prime Directive, with the motivation that it is for that civilizations own good, and we examined the problems with that back in “Smug Aliensâ€, but there’s a lot to be said about non-interference simply from the standpoint of not wanting to get dragged into someone else’s problems. Benevolent though is pretty much by definition someone who does get into other people’s problems, in order to help, whereas not getting involved at all is more of a distant well-wisher. These are the civilizations we’re focusing on today, the ones that actively help. This doesn’t mean they help with everything or that they do it openly, nor does it mean they have no self-interest in doing so, just that their main goal in dealing with us is to help us and by action rather than inaction. As we often say in regard to Aliens and the Fermi Paradox, it’s the motivation that’s key to figuring out how they would operate and how we might detect them. So, if aliens are somehow helping us, we can assume they did not think the best course of action for dealing with modern humanity was to openly land and start teaching, since they clearly are not. Though we might do that if we encountered some aliens when we get out there. There is a caveat though, a given benevolent agency might not act openly not because they were worried about it messing with our civilization but for fear of action by another agency. As an example, if you have some restrictive interstellar empire out there that doesn’t tolerate interference in civilizations like our own, for whatever reason, other groups inside or outside that empire might covertly sneak in and help. There’s also the matter of why and how they’re helping us. A common theme in science fiction is aliens showing up to basically lecture us on our evil ways. Back in early sci-fi this was generally on how militaristic we were or how we’d nuke ourselves into the dust, these days it’s often on environmental and ecological disasters, a good example of which is the original and more recent remake of “The Day the Earth Stood Stillâ€. The former made a bit of sense, if folks are aggressive and destructive, and you are not, showing up to talk to them about being nicer people fits as a way of engaging in your goal inside your own ethical constraints. The alternative might be an enforced peace, which they might be fine with doing too, but it takes a lot of effort to enforce peace and can border on being a Police State, so even if they are ethically okay with that they would presumably try the diplomatic and instructive approach first. Either way, this motivation, making us peaceful, makes some sense and again is common in sci-fi. It also fits for waiting if you don’t really want to actively intervene till forced, so you don’t need to step in until the civilization has developed an ability to destroy itself or maybe others on other worlds, thus partially avoiding the usual first contact issue of why now, and not a thousand years ago. However, more modern versions, like the reboot of “The Day the Earth Stood Stillâ€, suggest they are motivated by wanting to save us from our environmentally destructive ways and that does not make sense in any format requiring force or lecture. It is very unlikely that any civilization is actively trying to wreck their planet, and presumably your civilization has figured out various technologies and methods that permit ecologically sound industry and production, particularly as these are essentially prerequisites to actually engaging in interstellar travel… see our Generation Ships series for discussion of that, but fundamentally you need a pretty impressive power supply to move spaceships around and that pretty much eliminates all the environmental concerns of power production and also issues like clean fresh water supplies, agricultural land and deforestation, mining and recycling and some others too. Now you might need to encourage them to certain behaviors so they were continuing to pick ecologically sound options even while it was not always the most economical path, but that’s a lot easier to do when you just eliminated a vast amount of their existing problems and gave them a massive economic boost while you were at it. Sort of like meeting a primitive civilization and introducing them to antibiotics and vaccines. You still encourage them to the habit of washing their hands and other hygienic preventative measures, but they’ll be listening a lot more attentively when you just swept in and saved millions from the threat of this or that pandemic, even if you are being a bit condescending and smug about your explanations. The basic notion is that you don’t teach people how to behave better if the bad behavior stems from a problem you can simply eliminate, or at least massively limit, and folks are more receptive to your reasoning if you just gave them a hand. If you’ve got the technology to fix a problem, or at least change the specifics and expiration date, you are best off giving them that technology, then you can give the lecture. The exception being if the tech causes a new problem, like a better weapon, but while an assault rifle can kill people more effectively than a bow and arrow, either one gets the job done and which you’re both using doesn’t really matter if both parties are intentionally trying to kill each other and won’t stop till the job is done. A far smaller percentage of people die nowadays in war than used to, even though we have better weapons. The why is debatable, and there’s probably not a single cause, but simply having better weapons doesn’t mean more destruction, and that is something any species that is flying around interstellar space and talking about living peacefully is going to know and believe, else they wouldn’t exist. So, a benevolent species aiming to change our attitude on something isn’t likely to be averse to giving us technological aid, at least for the reason of self-destruction. That might not be universal though, it would apply to modern humans it would seem but maybe not prior human civilizations and maybe not to some species that was hyper-aggressive. Now we can come up with some special exceptions, but we have to keep two things in mind. First, while they might be very averse to giving folks technology, it’s pretty unlikely that would be a universal view among all civilizations, or even all the members of such a civilization. Second, they’re going to know that, and know that technology is likely to seep out anyway, and that’s likely to impact their decision-making process. If you know other civilizations hand out technology, or that members of your civilization will covertly give it out from good intent or sell it or even just that it will get accidentally exchanged, what’s the point of putting the effort into concealing it if its doomed to fail? When alternatively you can control its release to minimize negative impact. Keep in mind, scientific and technological progress don’t happen like portrayed in Hollywood, a lot of invention is just about it occurring to someone that a device should or could be made to do something, it’s a lot easier to get there if you see a device doing its job and how that’s handy, or reverse-engineered it from folks seeing it in action a lot and knowing some of the new principles involved. I couldn’t have invented a refrigerator nor could anyone living in a bronze age culture, but even having never made much of a study of it, ignoring the language gap, I could easily sit down with some bronze or copper smiths of that era and show them how to make one, especially an Einstein Refrigerator which has no moving parts and runs on fire. I know what it does, I know that it works, I know the basic principle, that’s all it takes with a little time and tinkering. That sort of approach could lead to Cargo Cults, folks with no understanding of the principles who simply mimic what they see, but Cargo Cults appeared when a civilization was busy doing something near another civilization, not with them, like airdrops of supplies to remote islands in World War 2, that isn’t likely to apply to interstellar visitors as you don’t really bump into a planet and regardless it assumes the civilization is contacting the other civilization with help in mind and actively involving themselves, not some big war going on. One could imagine two interstellar empires having a shooting war in a solar system with a primitive civilization observing it but that’s a different situation and scenario than today’s topic. Of course, speaking of religions and keeping in mind technology isn’t the only way to help, there is a good chance you’d see a lot of folks worshipping aliens who came bearing gifts, and indeed that is a common notion in sci-fi too. It’s got two problems though. First, if we’re assuming they are benevolent then they aren’t likely to be propping themselves up as false gods, with an exception we’ll get to in a moment. Second, such a civilization either has its own religion, or religions, or does not. If not, they presumably aren’t encouraging folks to worship them if their goal is to enlighten us, as they’d presumably view that as counterproductive. If the former, that they are religious, then it’s very unlikely they’re trying to impersonate deities, instead they’d either be trying to convert us for what they considered our own good, and that would probably be their top priority, essentially a missionary civilization, or they would not if they thought that was wrong ethically. However, they might be pragmatists, especially if they’re a small group dealing with an early civilization and one they don’t want to disrupt too much and pose as existing benevolent gods or simply as enlightened teachers who later were deified by history. That’s also a popular one in science fiction too, suggesting this or that historic scientist or teacher or religious figure was an alien, and not a bad one either from a strictly logical perspective. If you’re posing as a human, odds are good you’d be giving off a lot of telltales of abnormality in your behavior, the eccentric scientist is a pretty good cover story for that, and that applies to big thinkers in general. It’s not a terribly accurate stereotype incidentally but eccentric behavior is hardly uncommon in such folks and accurate or not, it’s not unexpected, which is what matters. This one fits pretty good too, because they are probably going to want to do more than just give us technology. I mean if I were going back in time to help farmers or smiths learn how to rotate crops or make cheap steel, I really doubt I’d be able to avoid making commentary on some things I thought they might find good, like abolishing slavery and instituting some human rights and due process, particularly as I wouldn’t have any moral qualms about that. That obviously gets into murky territory but as I said, once you get into the benevolent intervention game, that murk is unavoidable, you’re just trying to be mindful of the pitfalls and abuses that can accompany such behavior. Or not. A given civilization might be heavy handed with their intervention because they subscribe to the ‘for your own good’ school of thought in a major way. That would depend a lot on the culture in question, both the folks giving the help and the ones getting it. As an example, we have a notion called Uplifting, which is enhancing a species either technologically, physiologically, or neurologically, or two or all three, see that episode for discussion of the specifics but if I find a race of pretty intelligent critters, like dolphins, chimps, or elephants, I might give them a little genetic tweak to mind or body to make technological development easier. I’m obviously not asking them since they’d have no clue what I meant, so it’s not exactly voluntary. That is another way they might help us too, improving us, in their eyes at least, physically or mentally. Now if they’re showing up overtly and giving us technology, they might simply offer this as an option, mind or body alterations, but this path of help applies more to the covert approaches. And it can be very minimalist. As an example, if I encounter a fairly aggressive species I might need only do something very tiny, like tweak genes for their gland that produces their hormone for aggression to produce 1% less, or tweak the rate of growth of their equivalent of a pre-frontal cortex for making judgements to develop just a little faster or larger. Not even something outside their current bell-curve distribution, just something like the equivalent of tweaking average height by 1 centimeter or IQ from 100 to 101. Civilizations are statistical in a lot of ways, and that can show up a lot in your outliers. If you find out half your murders and fights are involving the 1% that have the highest of some given hormone or trait, moving that little average and distribution over just a little bit could drop that number in the outlier down to a fraction of what it is. If you find that 99% of your discoveries are coming from the folks occupying the top 1% of your IQ distribution, moving that over a couple points might massively increase how many were of the same intelligence as that 1% were. Or they might give us just a few little tweaks so we lived a bit longer or had better immune systems. This is obviously morally grey too but would seem to occupy lighter shades of grey than, say, culling folks with a given trait or outright engaging in major physiological or neurological enhancement. That might happen too, you might get some species that thought it was perfectly fine to show up and infect everyone with an engineered virus or nanobots that turned us into some sort of alien-human hybrid. That alien hybrid notion is popular in sci-fi too and the genetic alteration approach is a lot more plausible than interbreeding I imagine. The whole half-human, half-alien thing is pretty dubious from any sort of biological standpoint, especially when it’s an alien and human getting married and having kids like Spock from Star Trek. When it’s just the classic sci-fi alien, who for limitations of makeup or CGI basically just has a few minor cosmetic changes of appearance and behavior from humans, it seem plausible, but you’re way more likely to be encountering something that resembles you about as closely as a squid does and differs from you genetically by more than a tree does. I can’t really imagine us finding lots of folks who wanted to go marry and breed with a tentacular horror and I’d imagine they’d feel the same way about us. Although if the internet has taught me anything, it’s that someone, somewhere, probably would think that was fun and to each his, her, or its own I suppose. It's also entirely probable some advanced alien species isn’t exactly a species. It might be some federation of many alien races or it might be that they’ve just diverged a lot internally, as we discussed recently in the episode “Genetic Divergence and Civilizationâ€, given several thousand years and access to a lot of high-end genetic or cybernetic technologies, they might easily have a widely varying number of limbs and eyeballs even from folks who were distant cousins or even not-so-distant ones. There’s also the psychological differences too, both those hard-wired into us biologically and those that are cultural. A lot of our ethics follow from logical reasoning but often derive from paths influenced by arguably arbitrary cultural events that impacted us strongly. For instance, we worry about the dangers of colonialism but that’s from effective isolation of cultures leaving very large technology gaps and cultural differences, some planet that was a single big continent with easily navigated coasts and rivers, or more wanderlust prone inhabitants – which ought not be a strange trait for evolution to produce – might never have that particularly issue crop up and not come away with the same perspective or the dangers we associate with that. If your civilization was one where young folks routinely went on long journeys to find a new home or a mate and was expected to carry news and innovations along with them, you probably have a culture that is predisposed to just wander in and say hi and start airing their ideas and views rather casually, everybody is an anthropologist in their youth and none of their anthropologists ever developed a non-interference restriction. That’s a pretty minor difference, and so too, a civilization that developed on a world where a lot of plants had developed major narcotic properties, where one made folks more docile and suggestible, might have very early on gotten in the habit of dosing people with that whenever they misbehaved even as kids, their equivalent of spanking or telling a kid to go stand in the corner or hitting a troublemaker with community service for misdemeanors. They are likely to have a very different view on brainwashing than we do and be surprised if anyone objected if they mass-brainwashed us all to be less troublesome in their eyes. And again, ‘benevolent’ is pretty subjective. If you encounter a society that is pretty Darwinian in some regards, they might think it a genuine kindness to regularly attack primitive civilizations with just enough force to damage them to toughen them up, and do it periodically. Indeed, that’s the implied reasoning of the aliens known as the Shadows in the Babylon 5 TV series from the 1990s. We take that attitude to a degree too, that hardship and challenge bring growth and strength, and we would assume Darwinian concepts were known to almost every advanced civilization, so some might take it a bit more extreme than us. Same, if they’re a lot more interconnected than us, not even going into hive minds or the assimilationist Borg of Star Trek, they might think wiring us all up so we could hear or feel each other’s thoughts or moods was a great kindness. We see something similar in Alastair Reynolds Revelation Space series in terms of the Conjoiners, a partial hive mind who, while later switching to voluntary membership, start off as grabbing people for involuntary membership. It brings to mind the old saying, “With friends like these, who needs enemies?â€. Personally I think it more likely than not that aliens we’d meet one day would be more prone to benevolence than exploitation or conquest or extermination, but we might find their gifts a bit less than desirable, and if we end up in their shoes instead, helping out some civilization we encounter, we might want to keep that in mind. A theme for today was that while aliens are often thought to be reluctant to share their knowledge and skills, that doesn't really make sense, and certainly our own modern civilization doesn’t tend to feel that way. I’d tend to suspect a society based heavily around advancing knowledge and technology would tend to also be one that would lean toward wanting to share at least the basic and intermediate skills of any craft with everyone else. Of course a willingness to share skills isn’t the same as doing it well, and while a great blessing of modern times is that everything is out on the internet, it’s often not collected and presented in an ideal form for folks to find and learn. That’s where Skillshare comes in. Skillshare is an online learning community for creatives, where millions come together to take the next step in their creative journey, and Members get unlimited access to thousands of inspiring classes, with hands-on projects and feedback from a community of millions. Skillshare offers thousands of classes to improve professional and creative skills, but also a lot of simply handy life skills, like Michael Phillips class on how to brew an amazing cup of coffee. I suspect I’m not alone in being a big fan of coffee and he does a great job not just explaining the method of brewing but a lot of background and knowledge involved. If you’re a lifelong learner interested in picking up some new skills, I’d recommend Skillshare. Whether you’re a beginner, a pro, a dabler, or a master, Skillshare has thousands of classes on a wide variety of topics from experts to help you learn. If you’d like to give it a try the first 1000 of my subscribers to click the link in the description will get a 2 month free trial of Premium Membership so you can explore your creativity. Act now, and start learning, today. So we were talking today about how a benevolent alien species might act if it came across a younger species, and it stands to reason if they found someone younger to help or visit, someone older probably found them and acted likewise. That can only go back so far though, until you get to that first civilization… and maybe that civilization is us? Maybe we are the firstborn civilization in the Cosmos. In two weeks we’ll explore that notion in “The Fermi Paradox: Firstborn†Before then though, we’ll be returning to Jupiter to look at the possibility of turning it into a second Sun, a notion popularized by Arthur C. Clarke in his 2001: Space Odyssey series as something done by an ancient benevolent alien civilization. We’ll look at why and how we might be able to do that or something equivalent next week in “Summer on Jupiterâ€. For alerts when those and other episodes come out make sure to subscribe to the channel, and if you enjoyed this episode, hit the like button and share it with others. And if you’d like to support future episodes, visit our website, IsaacArthur.net, to see ways to help out or see our catalogue of episodes, book recommendations, and SFIA Merchandise. Until next time, thanks for watching, and have a great week! Ah, Genetic Engineering, the field of science that will one day let us ride around dinosaurs throwing pokemon at each other. So our topic today is bioforming and gene-tailoring, both basically extensions on genetic engineering, and initially I had thought we would keep it pretty practical and down to Earth, discuss things like CRISPR and the ways it can be used to fix health problems. We would look at ethical issues and potential benefits and concerns about this technology. And we will get to those, but then I found myself thinking, lots of folks have discussed that and discussed it well, and this channel does not generally focus on ‘Down to Earth’. Heck last episode I was talking about moving galaxies. So yes we will talk about the near-term applications and the ethical issues but we will push the envelope out a bit and explore some novel, even zany, applications of this sort of technology, though we will keep it the realm of what is allowed by known science or at least not forbidden by it. Which includes making dinosaurs, as in Jurassic Park, because honestly I can't think of many things cooler than riding around on a dinosaur and if you don’t think that’s awesome I think something is probably wrong with you, because that has to be ten times cooler than a horse or a Harley Davidson. Of course it is not as easy as in Jurassic Park, because DNA does get preserved for millions of years, but we will see today how you could do it anyway. How this technology can be used to recreate long extinct species and even engineer ones that never existed, like unicorns or chupacabra. Or even things which probably could not naturally evolve, like dragons or multi-headed hydras or intelligent trees. We also have potential practical applications, not just stuff like a species of corn that grows twice as much food or some algae that could tailored to be perfect for making biofuels and plastics but less obvious stuff like roads that grew and repaired themselves in ways similar to how coral reefs work or plants that could suck trace metals right out of the ground so we could harvest them rather than needed to mine them. Or even plants that might replace solar panels and let you just plug in to the field or forest for electricity. Stuff that just could not evolve naturally. Which does bring up the question of how we do this stuff and if it is ethical to do it. Yes it should be possible to make an intelligent tree or a human-horse hybrid, a centaur, or a human-fish hybrid, a mermaid, but is it ethical to do so? And how do we do so? For the ‘how?’ part there are a lot of options, but there are four approaches I wanted to look at briefly today. One is CRISPR, an exciting new technology people have been talking about a lot. Another is similar, use of retroviruses to go enact changes to DNA throughout an organism. The third is straight DNA Printing, which gives us the option to make strands of DNA from scratch straight off a computer model. And lastly we have the option of using nanotechnology, the Universal Assemblers we discussed some episodes back, to just get in there and make the changes at the molecular level if necessary. Before we jump into those, and we will be keeping them brief, I did want to take moment to differentiate Bioforming from Gene-Tailoring and both from Genetic Engineering. Bioforming we discussed in passing back in the Terraforming episode, as the alternative to Terraforming. When terraforming a planet you are trying to make it more Earth-like so people and Terran Flora and Fauna can live there. Bioforming, sometimes also called Pantropy, is the reverse, where you adapt Earth Organisms to live in Alien Environments. This does not necessarily have to be all that high-tech or alien, if you are dealing with a world already a lot like Earth but devoid of life. If it is not much like Earth, or already has life on it, you probably need to do some massive overhauling. Outside of science fiction you cannot land on an alien world with alien plants and animals and start eating them or introducing your own plants and animals. In all probability the best thing that will happen if you eat a bunch of alien fruits and nuts is that you will get very sick and spend a lot of time in the bathroom expelling those things from one or another of your orifices. A lot our own plants can be quite toxic, heck, as I was reminded when watching a recent episode of Cody’s Lab, a lot of regular edible plants contain cyanide, just in low enough dosages that we have adapted to be able to survive eating them. There might be some planets that work on similar enough biochemistry that you can eat the food, or some of it, but in all probability you cannot and if you introduce Terran Flora and Fauna either it will die out or it will wipe out the native life. Most of us would say those would be bad things, so the alternative is a fairly massive overhaul of our organisms to mix in with those native to that planet. This doesn’t necessarily mean tinkering with humans themselves, we might be able to make microorganisms we can introduce into our guts to helps us digest the food, but tinkering with humans themselves is on the table for today. So, obviously, is the ethical issue attached to that. Gene Tailoring is a bit different, it has no formal definition but it comes with an assumption you are making unnatural changes to an organism. It would not just be replacing a defective gene in a person with the one of the other existing versions of it in other people but probably making up a new gene from scratch, which is where DNA printing comes in. So for instance, color blindness tends to be hereditary and red-green color blindness, which affects a pretty large chunk of the male populace, could be fixed by taking the functional gene from someone without color blindness and sticking it in the color blind person. This is controversial but not nearly as much so as the idea of taking some genes that let you develop cones in your eyes able to infrared light and putting them into a person. Either adapted from some other critter or cooking them up in a lab from scratch, or just on a computer model and printing them. So for the purpose of this video, when I say Bioforming I am talking about altering an organism to exist in some new environment, rather than altering the environment, though you could do both. When I saw gene tailoring I am talking about alterations to people through genetics beyond the basic form. So not so much replacing a defective gene which causes diabetes or near-sightedness, and more about giving yourself a body that can win Olympic medals without practice or eyes that can see infrared radiation or getting wings grafted on to your body or a becoming a horse from the torso down. This also includes the mental aspects, improving or altering the brain or nervous system, as opposed to just fixing problems like Dementia or Alzheimer's or my own more benign neurological condition that makes my hands tremble and face twitch but otherwise leaves me sound in mind and body. It would be nice if we could snip out the defective genes causing that sort of thing and by and large those are not considered particularly controversial. There are folks who think even doing things like that is going too far, but too be fair there are people whose definition of natural would seem to exclude anything more advanced than sharp sticks and fire. I’m never entirely clear why I often encounter these people on the internet, but I think maybe smartphones and tablets are exempted from their worldview of evil technology. Of course that itself is a good example of bias since I am well aware that various primitivist approaches have wildly different technologies they disapprove of and reasons for doing so. For some it is simply about self-reliance and personal challenge, and it isn’t like we mock mountain climbers for not taking a helicopter to the mountain peak. We will be discussing the ethics of this stuff and trying for some neutrality, and indeed there are a lot of strong arguments against some applications of this sort of technology and a lot of others types too, but there is also a line between reasonable concerns and the ridiculous. I can easily respect the opinion of someone who thinks engineering people for higher intelligence is dangerous, but while can respect a person who believes we should not use unnatural chemicals as medicine, in favor of all-natural approaches, I cannot respect their view on the matter. Simply their right to have that view and their right to expect courtesy equal to what they offer me. It’s a hazy line but I will try to keep on the proper side of it for today. So let us talk about methods, and again I want to keep this fairly brief. I outlined four a few minutes ago. CRISPR, retroviruses, DNA printing, and Universal Assemblers. Those are just some of the methods and I wanted to touch on certain aspects of each before we move on. CRISPR has become a big news item and you can get details about how it works elsewhere, but essentially a CRISPR is a chunk of DNA where you get a repeating pattern, the pattern is the same forwards and backwards and is short, twenty to forty base pairs, essentially a sentence long snippet in the bookshelf that is your DNA. That sentence keeps repeating but in between it are short bits, the equivalent of single words, called Spacer DNA, and those don’t repeat, each one is different and it looks like they are essentially identifiers for pesky viruses and such your body has encountered before. When it encounters new ones it lays in another segment, a new bit of Spacer DNA and another repetition of that sentence. That’s CRISPR. But nearby that segment is an associated sequence, a CRISPR Associated or Cas gene. These basically can unzip DNA and cut it up, and are a major part of our immune system. What make it handy for genetics is that we can take the Cas and attach something else to it, a sentence of our choosing. And if we stuck it in a cell it would go find anything that looked like that and can add or delete it. So the CRISPR/Cas-9 stuff you keep hearing about is essentially hijacking an existing part of us, one that prevents viruses from hijacking our cells, and using it to snip out bad DNA. And it shows amazing promise as a tool to be used to let us cut out or add or modify DNA. Before this the popular talk was often of retroviruses. In most viruses DNA is transcribed into RNA, then translated into proteins. Retroviruses do that somewhat backward, their RNA gets transcribed into the host’s DNA which starts making copies. Like CRISPR we have the option of hijacking this to be used to modify DNA. Of course you could get into someone’s DNA with very tiny forceps and scalpels and change it. The problem is that for any case where you are not working on a single cell embryo, like an adult human with trillions of cells, it is kind of hard to get at all those trillions of DNA helixes and alter each and everyone one. DNA printing, which is just spitting out the chemicals that make up DNA one molecule at a time in the right sequence, is obviously handy for letting us make one copy of DNA, we can make anything our minds can imagine and which is chemically possible. The problem, besides us needing a way to deliver changes to trillions of cells, is that DNA is very long. And while we always show DNA as a pair of long strands, it generally is like a big ball of yarn, not like a long wire hanging between two transmission towers. It’s got something like 3 billion base pairs for a human, and genes usually are made up several thousands base pairs and you’ve got several thousand genes in your DNA. A normal ball of yarn might be a few hundred meters long, a few times longer than a football field, but our DNA yarn ball, if it were normal yarn width, would be thousands of kilometers long. An individual gene would often be as long as a football field. When the whole thing wraps up in a ball it would be about your size. Needless to say printing something out, one hairbreadth at a time but thousands of kilometers long is pretty time consuming. So DNA printing is awesome for making one segment, one gene, or even one complete set of DNA, but not for mass manufacturing billions and trillions of copies for every cell in a body. That’s what CRISPR, retroviruses, and some other techniques are for. What is cool about DNA printing is you do not need an existing gene, you can design one from scratch, so we do not have to find fossilized DNA from a dinosaur to make one, we can just make educated guesses about what it needs and compile it from scratch on computer. We can then print it, stuff it into an egg, and proceed. And if we like we can give them a temperament and intelligence more in line with, say, a horse. Of course that is essentially turning DNA and RNA and viruses into machines, which they already are but I mean in the artificial sense. We can potentially skip that by using the sorts of tiny little nanomachines we have talked about before, particularly the kind called a Universal Assembler, or specifically the Universal Molecular Assembler. Which you can tell to build a copy of itself or tell to go find a bit of DNA and cut it up and assemble it how you want. Now my main reason for mentioning this one is that I like to remind people that we do not have to use and either or approach with technology. Fiction likes to show us futures where people are genetically engineered supermen or cyborgs, not both. They tend to skip that such critters would probably be both, even from birth. Same as we have mitochondria in us that is effectively an alien organism present in every cell in your body, you could have machine DNA equivalents that hung around doing jobs like replacing an organism's bones with hollow titanium or growing the various brain implants contemplated in Transhumanism. There are no unicorns, or at least I’ve never seen one or met anyone who has, at least while sober, but a horse with a horn on it is not exactly a weird thing that could never evolve naturally. Horns are handy and common features in nature so there probably is some planet somewhere that’s got them. Alternatively something like a dragon, I mean a giant flying reptile that weighs more than elephant and breathes fire, well that is not too likely. Dragons are also awesome so science fiction is full of plenty of examples of them where the author spends a lot of time fudging around with how they could exist with some gene-tailoring. Maybe so, but they can certainly exist if you do not mind going a bit above and beyond genetic engineering to include either DNA that can make little machines too, or symbiotic passengers like mitochondria. So your dragon is otherwise organic but it’s got hollow bones made of titanium or kevlar or graphene and maybe its wings and scales incorporate those features to make it very strong and light. Maybe you include a photosynthetic element on the wings so it can feed itself partly on sunlight when it stretches out to subathe on the noon-time desert sands. There’s no rule that says a genetically engineered plant could not suck metals out of the ground and weave them into its own structure to make it sturdier than what cellulose and lignin permit. Maybe it is incorporated into their core structure or maybe they deposit it like coral into a long spire they grow up around. So you can modify the existing organism or make one up from scratch, and a lot of time you will need to modify the brain for many of things I’ll mention in a moment too, you cannot just give someone cones in their eyeballs that are sensitive to infrared and ultraviolet light and expect them to see new colors beyond the rainbow, you need to get in the brain and do some re-wiring too. Uplifting, the name for when you take an animal and give it a human-level intelligence, tends to assume the reverse case. For better eyes that can see additional colors we need to tinker with the brain also, but for a better mind on a cat or dog or dolphin we might need to tinker with the physical form too. Giving them different vocal cords or more nimble toes that can grasp tools. Probably tinkering with its reproductive system too since a lot of animals reproduce much more quickly than us and with intelligence and tool use comes a much lower chance of natural death. Not what we usually mean these days as a euphemism for old age. In nature a natural death usually means ending as someone’s dinner and before you’ve reproduced, which you can do much younger than humans can which is important since humans live a long time and take a long time to develop during which we need a lot more parental care and attention. So if you are uplifting animals to make them sentient and sapient you probably need to be thinking about a lot of other things you need to accompany with that. Like longer lives, tool using hands, slower reproductive rates with single births not litters, and slower maturation rates. So you can use it to make your pets smarter or maybe make entirely new pets like that cute critter from the old gremlins movie, or real life pokemon. Now, what people might do to themselves doesn’t interest me all that much except in terms of pondering the ethics. I honestly do not much care if someone wants to get their body tweaked, genetically or cybernetically, so they are ten feet tall and built like a linebacker with a souped up heart to support all that new mass. Needless to say it could be used to let people switch genders or be both genders or neither. Or if they feel like getting scales or fur or feathers or a third eye or extra pair of arms. That could look pretty awesome or scary or disgusting, but again it is Halloween when this episode comes out so I’m content with scary. What does interest me is useful applications, a type of corn that can use more light to grow with for instance. Our plants mostly use red light for photosynthesis and don’t use much green or infrared, and most of what the sun emits is infrared light, and most stars in the galaxy emit even more of their light in that part of the spectrum. Our yellow ‘dwarf’ star out masses about 95% of stars and is hotter than them, meaning that it produces much more of its light in the visible range than they do. Needless to say a little tweak that let plants use that spectrum for growth could hugely increase the biomass on a planet or make terraforming planets around other stars much easier. It would be pretty neat to be able to tinker with how plants deal with carbon and carbon dioxide to be able to use it to sequester carbon out of the atmosphere. The strongest materials we have now are made out of carbon so it would be nice to suck the excess out of the air and maybe put it to use making those. It would also be neat to have plants that could be planted on toxic soil full of heavy metals and not only thrive but maybe have fruits that grew on them full of those metals, so we could collect them for reuse or safe disposal. We cold have vats of black algae that used the entire spectrum to grow very quickly and could be turned into biofuel or plastics, algae is already very promising in this regard but one tailored to use every ounce of energy it got shined on it would be even better. Trees that grew meat… sounds kind of freaky, but if it’s identical to bacon in taste and chemistry, it’s nicer than killing a pig, I’d say. So you could make a cow that produced more milk, which we’ve been doing through selective breeding for centuries, or you could cut out the middleman and have a bunch of bacteria that just grew milk. And since apparently almost everything tastes like chicken I’d imagine we could find a recipe for growing that too, we have been making pretty good strides in lab grown meat after all. So plants that could produce their own fertilizers, plants that can maybe suck the trace amounts of valuable minerals out regular soil and concentrate it for you, essentially plants that can be used as machines for specific purposes, in this case mining. You might be able to grow computers, you might be able to have organic structures that grew according to blueprint and repaired themselves. You might be able to grow solar panels as plants. Maybe you could make roads that repaired themselves too, with some equivalent to how coral reefs work or critters that grow shells. Maybe you don’t need vats of algae growing biofuel but can have a tree that you can tap for ethanol like we do for maple syrup. Maybe you can make an organism that will actually grow plastic, shiny transparent plastic, in some nice dome form that you can use for greenhouses in the desert or domes on Mars. Plants designed to live in toxic atmospheres or ones to dense or thin for life or ones designed from the ground up to live in the vacuum of space. You could potential create entire ecosphere in a solar system. Maybe ones that could migrate between solar systems and seed whole galaxies. Lots of random ideas tossed out there, some probably are absurd, some others probably are not but sound that way. Just some imagination fuel, when this topic got suggested it came attached with the request to offer out every crazy idea we might use it for and I think I just nailed that. These are potential options for genetic engineering when you open the doors to full blown gene tailoring, especially if you are not just limiting yourself to the strictly organic. Okay, so we’ve explored the basics of why and how, and we have talked about both some of the useful things we are doing now or might do soon, and a lot of quite zany ideas too. So I suppose we ought to raise the ethical issues at last. When I started thinking about the ethical aspects though, trying to lay out the arguments for and against, two common themes struck me. The first was that almost all of them are not limited to just genetic engineering. For instance the ethics of using gene tailoring to enhance human intelligence or strength or endurance is essentially the same as those for using cybernetics to do it or performance enhancing drugs. The second is that these were not new arguments. We have been using rituals and herbs to try to make people healthier or smarter since long before we had science, and we have been using selective breeding of plants, animals, and even people for a quite long time. That science and technology make these things easier, and actually works, is irrelevant. Or it would seem so to me. In the past we have tried to do these things. Sometimes it didn’t work, even if maybe we thought it did, like many of our folk remedies or superstitions, sometimes it did work but imperfectly, also like many of our folk remedies and superstitions. Whether it worked or how well it worked does not change the ethics of doing it, for the same reason trying to murder someone with a stage prop sword and failing is still attempted murder. So we can say it is unethical to modify children so they grow up to be geniuses with the bodies of supermodels and professional athletes. We can say that it is doubly so because it pressures other people to do it to their own children. For that matter, what right do we have to modify a person without their informed consent? A thing which is impossible with a young child. And yet, we already do these things, and have for a long time. This does not make it ethical, we do a lot of things we probably should cease doing for ethical reasons and we certainly have tons of things we used to do and stopped doing because they were unethical. And yet we can frame many of the ethical issues of genetic engineering in the context of existing ethical issues. Throughout history we had tons of cultures that engaged in selective breeding for traits, and they knew they were doing it. People often do make decisions for their children, someone has to, and often those are not ones we would applaud. People already do feel pressured to do things to benefit their children which are questionable and do try to do things to give their child an edge, or to make sure they can keep up with the others. The line between encouraging your child to succeed and pressuring your child to do so is decidedly thin and ill-defined. Is it ethical to alter DNA? I don’t know but we’ve been doing it, deliberately, for generations, and the only difference is we did not know what DNA was. Is it ethical to alter someone’s DNA without their consent? I don’t know but it seems to me that it is akin to any other situation where you would act without the target’s consent. It may be wrong to force someone to have surgery to remove a brain tumor, even though it is clearly damaging their judgement and ability to make informed decisions. But if that is not unethical, why would it be so to give gene therapy to correct a similar ailment, like Dementia? Similarly, if is okay for people to refuse medical treatments for their children, then it would be for gene therapy too, I should think, and vice-versa if a parent can refuse a life-saving procedure for their child like a donated heart, then they can also refuse the gene therapy which might fix the defect. If we cannot ban such things as organ donation, then on what basis would we ban the gene therapy equivalent? If we can ban performancing enhancing drugs, can we ban performance enhancing genes, and what is the difference between the two which might make one bad but the other not? It may be unethical to tamper with the genes of plants and animals, yet we have done this for a long time too and typically not with that organism's best interest in mind but our own. I cannot say I always approve of such things, but regardless, be they right or wrong, they seem little different than intentional genetic alteration, except, again, that we are much more skilled at it doing it. And when it comes to bioforming, altering organisms to live in alien environments, I am not sure what the difference is between altering a dog to live on the Planet Dune where it never rains, and altering the local wildlife to adapt to it raining, but it seems no more or less ethical to do that then to wipe out the giant desert sandworms that dwell there and are killed by water or to tinker with them so they can now live in oceans not just the seas of sand. So, as is often the case when we talk about the ethics of this or that bit of technology on this channel, we do not come up with a yes or no, but we maybe come away with a clearer picture of what we should be considering. I suspect almost every aspect of genetic engineering will have its own case-by-case problems. So some food for thought, and I’d be curious to hear what you think about these matters in the comments section of the episode, or over on the Facebook or Reddit Groups, Science and Futurism with Isaac Arthur, which are often more conducive to discussion if you want to talk with others about the ideas we looked at today. Next week is going to be my collaboration episode with Joe Scott, where we will look at Dark Flow & the Great Attractor. The week after that will be the Stellar Compendium, where we are going to look at the big zoo of star types, including the strange ones, and demystify some of the terms used to discuss them. Subscribe to the channel if you want alerts when that and other episodes come out, and if you enjoyed this episode, please share it with others and hit the like button. Until next time, thanks for watching and have a great day! This Episode is sponsored by Audible Biotechnology offers us a road to virtually endless ways to modify, alter, and improve on nature… but should we use it to do the same to ourselves? So today we will be examining biotech and we should start by asking what we mean by biotech. We are likely at the start of what will be a long revolution in biotechnology which will change life for humanity as thoroughly as the industrial revolution and information revolution have, if not more so, especially given that it might involve changing people literally. The word “biotech†means a lot of things to a lot of people, so I think it would be useful to spend a little time discussing what we mean when we use the word in this episode. The most obvious type is genetic manipulation. In principle, if any person, animal, plant, or microbe has an ability, it should be possible to recreate that ability through genetic manipulation. This should allow everyone to be as smart as the smartest human who has ever lived, as strong as the strongest, and so on. It could allow us to hibernate during long journeys through space, or navigate by the Earth’s magnetic field. In reality, the possibilities are probably far greater than what has naturally evolved and happens to have not gone extinct. It could allow the restoration of long dead species, or the creation of ones which we’ve never seen, like walking trees, or intelligent trees, or trees that grow candy or bacon. I suspect that when most people hear the term genetic manipulation, what first comes to mind is something like CRISPR, or using tailored retroviruses as a way to alter the genes of a living person by adding, subtracting, or altering their DNA. This is known as “in vivo gene therapyâ€, and is such an incredibly risky and difficult approach that it may be very rare. Retroviruses are pretty sloppy machines, and tend to cause a lot of damage while making such edits, potentially resulting in cancers. On top of this, those viruses can also trigger dangerous and potentially fatal immune responses. Since this approach is akin to modifying an airplane while it’s in flight, it shouldn’t be surprising that it’s difficult and very risky. Of course, if it can be made more reliable it could hold a lot of potential, but we often instead imagine using more artificial approaches like tiny robots instead of viruses, which itself can be a fairly blurry distinction of life versus machine, especially given how tenuously viruses tend to meet the definition of life and that such machines would likely be reproducing and aping the viral approach to that. Be it nanobot or retrovirus, we still have a long way ahead before such methods would become available for mainstream use. An alternative to gene editing that might be more likely is known as ex vivo gene therapy. This is where you remove some tissue from a person, perhaps just a few cells, and conduct your gene modification on that. This approach is much safer, since it’s completely external. If there are any problems with the editing process, the cell culture can be destroyed and a new culture started. This method also makes available the use of some chemicals which might be tolerated by the cell culture, but are unsuitable for injection. Perhaps a chemical has some benefit for a culture of liver cells, but produces psychedelic effects on neurons: being able to modify those liver cells in isolation could be a handy solution to that problem. The third gene editing approach, and by far the most controversial, is germline editing. Folks often make the mistake in assuming this involves germs somehow as an analog to retroviruses, but it’s using the other, older meaning of ‘germ’ as a seed or sprout, and works from the premise of making your genetic edits from that first seed with its single DNA copy. This is where you would modify the genome of an embryo, which then is modified in every cell subsequently divided from that embryo, and grows up with those edits integrated into the future child or adult. Not only does this alter the genome of every cell that child is ever able to grow, but it also alters the genomes of that child’s descendents. The consequences of any decision to conduct germline editing will last a lifetime, perhaps many lifetimes, and could have far-reaching consequences indeed. But despite its currently controversial status, my guess is that germline editing is likely to be very widespread in the future, especially for non-human use. Incidentally, this is generally why I tend to like retrovirus and nanobot options over germline editing. They rely on using untold trillions of little viruses or robots to change every necessary copy of DNA inside a mature organism, which is trillions of times more work, but leaves the door open for agency. An adult would still be able to decide for themselves what to change about themselves, including whether they want to change themselves back if their parents modified them earlier and they, as an adult, decided they don’t want those changes. Whether or not parents have a right to modify their child’s genes, and how broad that right is if it exists, is an interesting debate, but one you can mostly circumvent if you have the option of waiting and the option of reversal. In general, we should probably expect gene editing of humans in the foreseeable future to be widespread but cautious. Swapping out dysfunctional or lower-performing genes for better-performing examples already found in the wild human genome is pretty low risk, but it’s difficult to imagine ethical ways for novel genes to be safety tested. Of particular difficulty would be verifying that novel genes don’t cause mental illness, as proving safety would require testing on a large population of sentient humans. Any other testing protocol would still allow some outlying cases to slip through. If you’re planning on genetically modifying people to be vastly smarter and stronger, you might have to worry about them going all hyper-aggressive and narcissistic and trying to take over the world, like the classic sci fi example of Khan from Star Trek. Needless to say, that’s hard to test out safely or ethically, so you’d probably take an incremental approach, even just when using existing genes. We also have to keep in mind that whatever approach most folks think is safe doesn't mean that’s all we have to deal with. If some mad scientist and ambitious parents decide to try making a person who is very outside the normal template, say they spliced in some squid neurons because they thought it would result in faster reflexes and overall mental augmentation, we’d still have to deal with that person made by that process. Similarly, while someone like Khan might be imprisoned or executed for crimes committed while trying to take over the world, any children they had would still presumably enjoy the same rights and if the Khan’s kids or the squid-person wanted to set up families that is something of a dilemma. An area that is often neglected when people talk about sci fi biotech is pharmaceuticals, but it’s important not to underestimate the enormous potential still left in the realm of drugs. In particular, developments in genetic research are assisting the development of new pharmaceuticals in a variety of ways. Better understanding of what genes are doing - especially when they malfunction - can also point the way to new drugs. For example, if a malfunctioning gene is causing a serious health problem by producing a malformed protein, you might solve the problem by supplying the right protein in a pill. If the malformed protein is directly harmful, you might solve the problem by making a drug that binds to it, blocking its effect. If you want to introduce a highly complex molecule into a person’s cells, a more efficient route than injecting them with that molecule might be to inject them with messenger RNA, or mRNA, which codes for that molecule. mRNA serves as instructions that the cellular machinery follow to produce complex molecules in your cells. Incidentally, this is how some of the COVID-19 vaccines work - by tricking your cells to manufacture the spike proteins present on the surface of the outer shell of the virus. Beyond more familiar applications of pharmaceuticals, there are also some ways they might be used in combination with genetic modifications. You might control novel gene expression by making the gene require a chemical or element that it will never encounter in nature. Some gene-tailored animals that needed Tungsten to live, for instance, are easily supplied with tungsten but not from random plants and animals in nature. This approach is potentially handy for controlling tiny designer microorganisms, viruses, or even nanobots we might make in the future. When pharmaceuticals can’t fix the problem, you might resort to cloned transplantation. Failing organs or amputated limbs could be grown as part of a full human body, or with more advanced techniques, as individual parts. It’s likely to be a slow process to grow adult-sized body parts from an embryo, but there is likely a lot of potential for speeding up that growth rate from decades to mere years or months. Obviously the preferred goal is just to clone the needed organ, not a whole person, science fiction has a lot of examples of the latter case, people grown to maturity just to serve as an organ bank for another person, or for a full body transplant of someone who is old and plans to transplant their brain into a younger clone. Being able to grow the organs individually circumvents that issue. Being able to take donated organs or advanced prosthetics and implant them into people with no fear of rejection is another goal of biotech, and something that overlaps with the less-discussed fields of synthetic or xeno cellular implantation. Xeno Cellular Implantation is the implantation of animal tissues modified to be compatible with human biology and immune systems. For example, you might implant modified bird cells into a person’s scalp so they can grow feathers, or cuttlefish cells into a person’s irises to produce eyes that change color depending on mood. Tissues might be living cells, or non-living scaffold material which is then colonized by human cells. The example you might have heard of is washing a pig heart free of its material until just the protein scaffold is left beneath, on which we may grow a human heart. This might be done inside or outside a human. Currently non-living scaffolds from pigs are used to grow organs from human stem cells. Since the non-living scaffold material contains no cells, it generally doesn’t trigger an immune response when implanted. If you want to produce complicated structures already present in the animal kingdom, it is much faster and easier to produce them this way rather than trying to program those structures into the genome. These techniques could also be used with fully synthetic cells which do not come from nature, but were instead designed by engineers from the ground up. Tremendously useful things can be done by modifying nature, but at some point in the past we stopped spending so much time modifying parts of trees and rocks and instead spent time casting metals and weaving carbon fiber. It seems likely that fully synthetic biology will provide advantages over modified natural biology in certain situations. One type of biotech that is almost never depicted in sci fi is engineered microbiota. Microbiota are the various microorganisms which live on and inside of our bodies. Engineered microbiota can be naturally evolved organisms implanted from a different individual, domesticated organisms, or fully synthetic organisms designed by engineers. The gut microbiota can be used to produce and administer pharmaceuticals, detect ingested substances, control appetite, and metabolize previously indigestible substances - for example, lactose. Some people never develop dental cavities or obesity despite eating the same diet as those who do. Often this is due to a difference in microbiota. On the other hand, perhaps the most wildly exaggerated type of biotech in sci fi is mechanical implants or cybernetics. Cyborg sci fi generally uses cybernetics for shock value, so they’re depicted as bulky, intrusive, asymmetrical, and almost always penetrating the skin. The writers and special effects team are specifically shooting for inhuman and disturbing appearances, perversions or adulterations of humanity, and as is often the case for science fiction, the science part often suffers for the fiction. Needless to say, adding a 150 pound steel robot arm in place of a flesh and blood arm doesn’t allow you to lift enormous weights as the arm is still attached to your flesh and blood torso. In fact, you would likely struggle to even stand up straight due to the asymmetrical weight load, so you would have to do a rebuild basically from the ground floor up and that shouldn’t look all non-symmetric and haphazard, though I suppose a cyborg sub-culture might have big cyberpunk roots and enjoy that look. Also any device that permanently penetrates through the skin is prone to infection. In reality, mechanical implants will likely only be used when a biological solution is not yet available, either not being invented yet or because there’s a long lead time in manufacture, like it takes a year to clone a lung or heart or arm and you get the cybernetic version in the meantime. They will tend to be as small as possible, as soft as possible, and will avoid breaking the skin whenever possible, at least for physical augmentation, situations like mental augmentation by including digital memory implants or interfaces might need to be very inorganic. One of the most useful implants would be a digital radio circuit able to communicate with the future equivalents of bluetooth and wifi. This would allow internal systems to communicate with worn objects, and objects in the environment. For example, you don’t need to implant large quantities of digital memory. Instead, you wear a small gadget on your person which contains the memory chips, and this gadget communicates with the implanted digital radio. This type of neural radio would also give one a communication capability that would have some similarities to telepathy. You might be able to communicate entire concepts or emotions, or you might just be limited to something like hands free texting or silent phone calls. Even with the more limited versions though, people with this ability would seem connected in a way that is qualitatively different than what is possible via a cell phone. The cultural differences this would produce are likely to be analogous to trying to explain internet meme culture to someone who has never seen a computer. The second most useful implant would probably be input and output taps on your sensory systems, giving you access to augmented reality, virtual reality, and sensory recording. With the audio tap, you can play music with perfect fidelity without headphones. So long as your neural pathways are intact, it doesn’t even matter if your hearing has been damaged. You can turn off background noises, or the steady whine of tinnitus. You can play audiobooks and podcasts while showering or scuba diving. By linking to an external gadget capable of voice transcription and real time language translation, you could mute the actual voice of someone speaking in a language you don’t understand, and replace that audio feed with the translation. With the video tap, you could overlay a wide variety of augmented reality elements, including anything you currently look at your phone to see. If that sounds annoying, imagine the display as less like a bunch of obnoxious cluttered icons, and more like a small window that you call into existence when you perform some gesture, for example perhaps reaching into your pocket. It behaves very similarly to a cell phone except you can resize it to be as big or small as you want at the moment, and when you let go of it, it floats in midair. If you want, you can pull more windows out of your pocket. But they weigh nothing and they don’t make awkward, pointy bulges in your pocket. When you’re done with it, you just put it back in your pocket to dismiss it, or maybe just blink a quick pattern. Recipes or tutorials could hover in front of you as you try to learn a skill. Multifunctional appliances used to have zillions of buttons and knobs, but then they started replacing that with touch screen interfaces. In an era of ubiquitous augmented reality, appliances will have almost no hardware interfaces at all. They’ll be stylish and sleek. If you need to make an adjustment to your breadmaker or 3D printer, you’ll just pull out a virtual interface that becomes as large as you need it to be. And when you’re done, you make the interface disappear again. They’d probably have no other buttons, just a jack for manually adding some universal control device if needed. They might not even have power cords, as we are making progress on wireless power transmission and that too might be a very handy way to power some internal machinery on a person, like implants or nanobots. You could view movies on arbitrarily large, virtual screens, and even dim the rest of your vision if you want. The movie might completely surround you, as though you were inside of a spherical screen. Go further with this concept, and you can imagine replacing all of your sensory inputs with a full virtual reality. If the computer generating the virtual imagery is smart enough, the VR experience might tailor itself to the real-world environment around you to prevent injury. Doorways and staircases would still be there, but they might look like a dungeon portal or a marble staircase from a mansion. Full VR would presumably benefit from an olfactory and taste override, so you could smell the jungle or taste elvish cooking. Humans have a lot more senses than the commonly claimed seeing, hearing, smelling, tasting, and touching. For example, touch could be broken into a tactile sense, proprioception, temperature, pain, and balance. Hunger and thirst don’t seem to easily fall into any of those categories. Some of these senses can be kind of dangerous to mess with, though. For example, it’s hard to imagine much good coming of messing with one’s sense of balance, unless you’re lying on the ground. Messing with proprioception (which is your sense of where your body parts are located in space) seems even more dangerous, as you could be flailing around without realizing it. Pain overrides might take some people aback, but at least moderate levels could presumably spice up video games. Conversely, the usefulness of being able to dampen down severe, natural pain goes without saying. It’s still not without dangers though, as pain often serves as a warning that you’re doing something you shouldn’t be. Presumably, plenty of injuries will result from people using pain dampening for stupid things, but that’s also the case with literally every technology ever invented. So how do you interact with all of these virtual objects? One way would be for a computer to read the neural signals actually produced by your retinas, and use that to determine where your hands are, assuming they’re in your field of view. A better method might be to tap into the neural circuits involved in your sense of proprioception. Either of these techniques would allow you to use your hands and fingers to interact with virtual objects and user interfaces. As we looked at in our episode on Mind Augmentation, we also have the learned and programmable Universal Remote option. We can currently insert a few thousand leads into animal’s brain that would react to stimulation, which is what Neuralink has been working on for the last few years. In a human, these could act as a rather deliberate mental button the person learns to mentally push, with each connection being something a person could learn to flip by thinking in a certain way, much like flicking a finger or blinking, and this could act like some blank keyboard we could set each mental button or hotkey combination as a control for some device and the person would learn to be rather deliberate in flipping it. This gives you all the advantages of thought-control without the concerns about accidentally activating it, especially if its a mental button combination, as it would be more akin to accidentally punching in your pin code or accidentally saying a specific sentence. You’re not going to accidentally write a contract, sign it, and file it while you’re asleep. Such neural augmentation is something we can already do, on animals anyway, and I suspect this will be where we see our first thought control devices emerge from. But presumably it would eventually be possible for a more invasive system to read your intentions directly. Rather than opening a virtual user interface for the air conditioner, you would simply desire the temperature to lower slightly and the machinery would respond. This is often how such things are depicted in science fiction, but reading intentions is likely to be a far more complicated task than simply reading sensory inputs. But as I said before, these types of implants would likely only be mechanical until they could be replaced with biological versions capable of doing the same things. One technique that’s almost never discussed is what we might call “neural shapingâ€. This would be the artificial guiding of a person’s own neurons to produce engineered circuits. For example, one might implement digital calculator circuitry in a tiny corner of your brain, giving you the ability to calculate the cube root of a 10 digit number as quickly and easily as you parsed this sentence. It also allows wiring shunts around neural damage/scarring, enabling us to cure most forms of paralysis, and some mental illnesses. Lastly, there is the possibility of nanobots, and as I mentioned earlier the line between them and something like a retrovirus or engineered microorganism can be blurry. But I think it’s reasonable to say the term nanobot should only be used for things which don’t already have a good name, and thus would not apply to bacteria, viruses, or enzymes. This is more to do with defining our terms for the sake of easy discussion than accuracy. The capabilities of these devices in fiction are often either wildly exaggerated, or just as often, wildly underestimated. For a nanobot to work it needs some systems which are very challenging to engineer at nano scales including power, data processing, and sensory input. It will also produce heat and get worn and torn by doing activities, which is the missing bit that prevents them from being the super-fast magic wands sometimes seen in fiction. The faster a mechanical device works, the more damage it causes to itself for each activity, and the more energy it needs to do that activity, generally speaking, while at the same time it produces heat faster simply from doing more things in a shorter time. As is often the case with technology, the real bottleneck on it is getting rid of the heat, and we explored this notion in more detail in our episode on the Santa-Claus Machine. Of course, to make heat it needs to have a source power that’s fueling the work it does to produce heat as a waste product. The most readily available sources of power in an organism are either blood sugar and oxygen, or beamed power from an external source. The latter is sufficient in a clinical setting, but can be awkward to maintain as part of day to day life. Beamed power for nanobots is more complicated than at macro scales due to minimum size restrictions on antennae versus wavelength. One alternative is the multi-tiered approach we sometimes discuss for nanotech, where you have bigger microscopic factory and controller bots who produce and manage many specialized species of nanobots, and in a similar way to how mitochondria produce fuel for our cells, you might have a large control bot producing some nanobot-specific fuel via beamed power. There are a lot of chemicals that can be used as a fuel and assembled to provide abundant power, and this might make a good way to prevent problems like grey goo - where nanobots who build other nanobots get loose and turn everything on a planet into copies of themselves. In the same way a rare element or alloy could limit excessive production, a control-fuel specific to the body, or to certain situations, could provide an extra layer of safety. Data processing would also consume a large portion of a nanobot’s total power budget, and space is limited for complicated logic circuits. Sensory input is important too, as you probably only use nanobots if you have a task that needs to be done at a particular location in your body, but not in others. Most importantly, they might not self replicate. Designing a device to self replicate is more challenging than designing a similar device that doesn’t, and requires additional hardware, resources, and capabilities. It also raises enormous liability risks in the event that it colonizes people without their consent, or replicates out of control within the intended host. Again this is why the larger microscopic, or even macroscopic, robot factories and control centers we discussed a moment ago might be handy, potentially with many tiers of bot, each manufacturing the next lower tier of smaller robots. An important subject worth mentioning with networked biotech is data security. A complete VR sensory overlay sounds like amazing fun until you contemplate someone hacking your hardware to blind and deafen you while cranking your pain levels up to maximum. Or the hacker could compromise your sensory taps in order to see and hear everything you do without your knowledge or consent. More advanced implants allow more advanced hacks, allowing the hacker to literally read your thoughts or expose you to fake realities. Hacked nanobots could do whatever nanobots can do, and it won’t be pretty. So what’s possible with all this stuff? I’ve already mentioned a number of applications here, but the possibilities are almost infinite. Other easy stuff includes curing all genetic disorders forever and using vaccines and other immune system enhancements to eradicate many contagious diseases the way we have eradicated smallpox. Cancer is an inherently tricky disease, but survival rates have been increasing and will likely continue to do so for a long time. Appearance modifications have always been on the cutting edge of medical science and this will undoubtedly continue. The trend toward increasing obesity will suddenly go into rapid reversal. Noses and jawlines will be sculpted, and sometimes in ways that are inheritable. Presumably there will be a brief period where there are suddenly large numbers of people walking around looking like Barbie dolls or Conan, and possibly a phase afterward where this was seen as excessive and tacky. I mentioned that early cyborgs might embrace the cyberpunk genre and intentionally go for the jarring or gross imagery we often see with cyborgs in that genre, while others would presumably try more desperately for a natural human look the more augmented they were, like getting moles, baldness, or liver spots added. So that could go either way, with folks embracing inhuman forms, or idealized human forms, or very natural forms, and we’ll probably have periods and subgroups doing all of the above in various ways. A lot of the stigmas we have about body alteration have to do with safety and cost, and concerns about the psychology of the person doing them when we view those as potential problems. We view getting a rhinoplasty to alter the nose to a more preferred but normal human shape as being vastly different than putting on cosmetics that include colors found on no human skin, because the latter is cheap, safe, and fast to add or remove, so why someone might choose to do it doesn’t raise concerns about an unhealthy mental state or body image. In a civilization where you can change physical characteristics cheaply, quickly, and safely, and change them back again cheaply, quickly, and safely, you would presumably see a lot of folks doing so, and with less concerns about mental health and body image. Extensive Biotech should let people live longer, and they'll be healthy for longer too, so I would not be surprised if folks felt like changing things up physically from time to time. I mentioned mental health a moment ago and Biotech has a role to play there, as well. Mental health problems such as clinical depression, schizophrenia, and anxiety disorder are likely to become less and less common as we develop a better understanding of the causes, and better drugs and implants to help us treat them, as well as better counseling techniques I would hope, but we’re focused on biotech today. Certain gene variants are likely to be associated with certain mental health problems, and Biotech should allow options for easy early detection and intervention. Augmentations - possibly excluding cosmetic ones - are likely to creep in slowly and quietly unless some avenue for unethical human experimentation suddenly opens up. The risks to subjects being augmented are literally life and death, and the risks to organizations doing this research are severe financial and reputational damage, possibly even criminal penalties if everything isn’t above board. A certain amount of risk is likely to be viewed as acceptable when battling leukemia or MS, whereas scientists taking risks to add cat ears to people is likely to get a lot less leeway or sympathy when something goes wrong. One of the big risks is the potential for unanticipated interactions between different biotech treatments. Maybe a rare gene variant is discovered that is associated with cavity free teeth, and another one is discovered that is associated with champion weight lifters. Great! So, a generation of parents pays gene clinics to add these two discrete genetic modifications to their embryonic offspring. Unfortunately, when the children reach middle age, it’s discovered that the specific protein forms produced by the two gene variants combine to leave plaques in the brain, resulting in early onset dementia or hyper-aggression in the mid-life. Doctors have been administering these two genes to kids for decades by the time the interaction is discovered, and now you have a bunch of musclebound, cavity-free lunatics wandering the Earth, presumably turning to cannibalism with those perfect teeth of theirs. In the more distant future, people living in space habitats and colony ships will likely no longer experience muscle wasting or other maladies which result from long periods in zero G. Their tissues might be made tougher to allow them to hold their breath for long periods of time while working unprotected in space. You might add something like an additional eyelid, like cats have, with the intent of allowing folks to keep their eyes open in a vacuum, where liquids normally freeze or turn to gas. It’s uses in turning desolate planets habitable, either by molding the planet to be more earth-like, terraforming, or sculpting species to be more adapted to that planet - Bioforming - are topics we have examined on other occasions, but are clearly enormous. Biotech is potentially both a great danger to humanity, but also a great potential boon, as is often the case with an emerging technology. But it differs from most, as it doesn’t just allow humans to alter their environment or interact with it in novel ways. Biotechnology lets us alter the human itself, for better or for worse. So we have a couple of announcements along with our upcoming schedule, but first... Last week we were looking at the impact of Multiverses on the Fermi Paradox and we mostly looked at the alternate reality types of Multiverses, not those dealing with older Universes or parts of our own Universe beyond the edge of the Observable Universe, where the CMB originates, the Cosmic Microwave Background Radiation, and it's a topic we’ll probably look at in the future but I wanted to give a shout to my friend Brian Keating, host of the Into the Impossible Podcast which is also available here on Youtube. Brian’s been one of the strongest forces for conceiving and pushing forward research for Cosmic Microwave Background Radiation, having worked on BICEP2, and he’s currently the Director of the Simons Observatory under construction in the Atacama Desert that will continue that research. He’s also the author of the book “Losing the Nobel Prize†which discusses the BICEP experiments but also zooms in on some problems we have nowadays with how we go about these super-large or important research projects and how it might be hindering scientific progress. It’s a wonderful exploration of how scientific progress takes place and the audiobook version is excellently narrated, so I’m glad to name it our May 2021 SFIA Audible Audiobook of the Month. Audible has the largest collection of Audiobooks out there, indeed it is so large you could hit the play button and still be listening to new titles a few centuries from now, and as an Audible member, you will get (1) credit every month good for any title in their entire premium selection—that means the latest best-seller, the buzziest new release, the hottest celebrity memoir or that bucket list title you’ve been meaning to pick-up. Those titles are yours to keep forever in your Audible library. You will also get full access to their popular Plus Catalog. It’s filled with thousands and thousands of audiobooks, original entertainment, guided fitness and meditation, sleep tracks for better rest and podcasts—including ad-free versions of your favorite shows and exclusive series. All are included with your membership so you can download and stream all you want—no credits needed. And you can seamlessly listen to all of those on any device, picking up where you left off, and as always, new members can try Audible for 30 days, for free, just visit Audible dot com slash isaac or text isaac to 500-500. As a sidenote, this episode and the one from two weeks back, Post-Human Species, began as a a single episode suggested by a pair of our regular editors, Jason Burbank and Jerry Guern, and evolved into two separate topics, and maybe a third for down the road, each of which they assisted in writing with Jason being the principal co-writer of today’s script and Jarry the Post-human script from two weeks back. I’ve said it before and will say it again, it’s awesome to get to meet and work with so many talented folks, and most times they come right from our own audience, pitching an episode idea to me or volunteering some time to edit script or make graphics. On a personal note, my wife Sarah and I are moving this month so there may be some disruptions, delays, or errors as we get out and over and settled into the new place and studio. It's more out in the country so I can further enjoy solitude and the hermit life, and Sarah can move and expand her blueberry farm and start her new beekeeping hobby - which I blame in part on my friend Cody don Reeder from Cody’s Lab - though mostly for me finding them interesting and safe enough to have hives in my backyard. If you’re looking for some fun stuff to watch while waiting on our next episode, Cody’s Lab and Brian Keating’s “Into the Impossible†both contain endless hours of fun and mentally stimulating content. Speaking of those upcoming episodes, this was our first for May and we have plenty more ahead. Next week we will move on to Alien Languages and how to decode them, then we have our mid-month Scifi Sundays episode on Laser Pistols, Lightsabers, and other scifi weapons. After that we’ll be discuss Arcologies, giant buildings containing whole communities and ecologies and how to design them, before wrapping up our episodes with Solar Flares and their impact on the Fermi Paradox. Then Closing May out with our Monthly Livestream Q&A on Sunday, May 30th, hopefully from our new studio. If you want alerts when those and other episodes come out, make sure to subscribe to the channel, and if you’d like to help support future episodes, you can donate to us on Patreon, or our website, IsaacArthur.net, which are linked in the episode description below, along with all of our various social media forums where you can get updates and chat with others about the concepts in the episodes and many other futuristic ideas. You can also follow us itunes, Soundcloud, or Spotify to get our audio-only versions of the show. Until next time, thanks for watching, and have a great week! This Episode is sponsored by Skillshare Black holes are often portrayed as scary world-eating monsters, but what if they are actually the batteries that will power our future among the stars? So today we are looking at how we can potentially use black holes in the future, and it’s a topic we actually covered early in the channel but I thought it deserved a second visit and an expansion. Black holes offer a lot of options for any civilization that can master them and it’s too much for one episode, so we’ll do a crossover series looking at their implications for some of our other episodes over the next few months, and today we will focus on their use in moving spaceships in our Generation Ships series. We’ll follow that up with an Outward Bound episode on Colonizing Black Holes, and then a visit to our Space Warfare series with Weaponizing Black Holes. But we should start by talking about what black holes are and what they aren’t, and how artificial ones might differ from natural ones and the various ways we can draw energy from them. Contrary to popular belief in fiction, black holes do not just suck material into them, indeed a star that’s turned into one has a lot less gravitational force than it used to and you could normally fly by one far closer than you could fly by a star of the same mass without being harmed in the least bit. It’s common to say that black holes are so massive that even light cannot escape them, but this is wrong. It’s less common and less inaccurate to say that black holes are so dense, that even light can’t escape them. But both remarks paint a false portrait that’s only right because our most common known examples of black holes are those naturally created by stars dying, which are of course quite massive. There is a concept in physics called an event horizon, which like the normal horizon on Earth, is a place where you can’t see events occurring beyond it. The difference is that on Earth, if you live in a village you can walk over to that horizon, see what’s going on, and walk back home to tell everyone what you saw. Obviously if you lived on a planet that was a big balloon, constantly expanding, you’d have to walk further to get to that horizon as it’s further away on larger spheres, and you’d have to walk faster than it was expanding in order to take a look and come home. At an extragalactic scale, this is gives us something called the Cosmological Event Horizon, from the expansion of the Universe, and in general in physics it means light speed because that’s the fastest we, or any information, can go. While a Black Hole is a name more fitting for the Event Horizon of an object, where gravity prevents light from escaping, rather than what that object is, we’re rather stuck with the term these days. Every object in this Universe has gravity it gives off, based on its mass, though in fact it’s the total energy it has, not its mass that really matters, mass just happens to be the type of energy most usually relevant for this. The gravity generated by this pulls on you and there’s a speed, based on that mass and how far you are from it, that you could be moving away from it so you’d never be pulled back to it and thus would escape… the escape velocity. The equation for this is just the square root of twice the mass over the distance from that object, usually we’re talking about launching from its surface so that distance is that object’s radius. Looking at that equation though, you’d note that if the mass increases or the distance from it decreases, the escape velocity will rise, and if either the mass rises enough or the distance drops enough, that escape velocity will rise until it reaches the speed of light. It doesn’t magically stop there or anything, you can go higher, but no photons are going to reach you from that place, you will see darkness even if someone were shining a flashlight at you from in there, a black hole, and you can’t see what they’re doing, as they are over the horizon where you can see events. Any mass, at all, is going to have a distance this would occur at, but it’s usually less than the radius of the object and once you get lower down, a lot of the mass generating that gravity is above you and has to be discounted. If you could compress it all down to a tiny point, then any mass would have an event horizon, but to generate an event horizon the size of a typical living room, you’d have to compress the planet Jupiter down into a space that size, and Earth would have to be compressed to the size of a marble. The problem is, when you compress stuff it heats up, and little particles that are hot enough can escape from a planet if you do, and naturally occurring massive objects are inevitably composed mostly of hydrogen and helium, which fuse and release more heat shoving things apart. Even if you took iron, which cannot fuse, and packed it all in one place, the heat released as it crunched up would vaporize those outer layers and blow them off, so just stacking endless trillions of tons of iron somewhere would only make a black hole if you took your time about it, letting it cool as you added mass. Hypothetical Iron Stars collapsing into black holes is something we looked at in Civilizations at the End of Time, and can exist exactly because they have eons to cool down as they slowly form by quantum processes. Given the series title, this approach isn’t too fast, though you can do it faster than that. So black holes just don’t form naturally below a certain mass, a mass greater than our own Sun, but that only covers natural formation and we’re not limited to that approach, and the physics doesn’t change for how they operate if they’re smaller either, though a lot of their properties do. Now, we’ll focus on small artificial black holes throughout this series but there are ways to use existing black holes, natural ones, for useful purposes including propelling spaceships. The problem is that naturally occurring black holes are really very uncommon. Only about 1 in 1000 stars that form is massive enough to die as a black hole and they tend not to be located where they’d be very useful for the typical civilization, particularly considering their presence would be prone to discourage civilizations evolving there. We’ll talk more about how civilizations could find them useful in Colonizing Black Holes in three weeks, but in terms of running starships, we do have a few options. First off, the easiest way to locate black holes these days is by their accretion discs, matter that falls into orbit around them and slams into other matter as they slowly decay in orbit and fall down. The same as anything falling down a gravity well, it gains a lot of energy as it does so, and will release this as radiation, which so long as it does it outside the event horizon can be captured and used like any other energy. This is the conceptually easiest way to tap black holes for power, you spray a jet of matter at it, aiming just off to the side so it enters a close and elliptical orbit, and that jet will create a nice whirlpool of matter that gets crowded and hot and turns that black hole into a big power plant. For a non-rotating black hole, such a process can let you achieve a 6% matter to energy conversion rate. That sounds measly, but remember that’s matter to energy, E=mc², throw a gallon of gasoline on a fire, 2.75 kilograms of mass, and you’ll release 120 million joules of energy, throw it down a non-rotating black hole yielding a 6% mass-energy conversion, and you will get almost 15 quadrillion joules back, 124 million times more energy than burning it got you, of course the black hole gets even more, but it did a lot of work to get that so it deserves the lion’s share. This is also much better than using a Sun, since Fusion generally doesn’t even give you 1% mass to energy conversion, and most stars don’t fuse all their matter and take a long time doing it, indeed the most efficient ones live half of eternity, whereas the really bright ones that give off the most power tend to explode long before they’ve burned more than a fraction of their mass. Your default black hole is thus a way more efficient power reactor and you can also throttle it a lot better than a star. You are also decently likely to find a nice big source of matter nearby a black hole since even though they have explosive births, a supernova is not actually powerful enough to rip apart gas giants in outer planetary orbits. In fact, one of the ways to find a black hole is to notice a brighter binary companion wobbling around it. Another way to make one is to start with a less massive neutron star and stuff it’s binary companion into it too. Needless to say, if you’ve got a giant power reactor you’ve got an engine, but in this case it would be a slow one like the Shkadov Thruster method of turning a star into a big spaceship, except you can achieve a higher final speed with one, though it will be gaining mass while you do this. We’ve a better way of converting black holes into engines we’ll get to in a moment. The other obvious method would be to fly a spaceship near one to slingshot off it, but you are not a cloud of gas so you can’t afford to get too close. This still offers a fairly nice bump in speed even to ships moving fast enough to consider interstellar trips on reasonable timelines, but it’s also a very good way to change your direction on the cheap, one reason black holes might be popular colonial spots down the road, ships planning really long trips might tend to aim in their general direction so they can change their course closer to their destination, which might be prone to changing if you’re part of big colonial efforts where folks might need to change plans as they get closer and find out more about possible destinations. However, we’re not a gas and we are not likely to have thousands of ships trying to use one for course changes all the time, so it’s actually better to turn it into a big power plant and use that to run giant pushing lasers or matter beams to shove ships with instead, not to mention power a civilization nearby... or vaporize one, which we’ll discuss when we get to Weaponizing Black Holes. Despite these problems, we have some other ways to tap black holes of this size for power and the first is just about remembering what I said about non-rotating black holes earlier, and in nature they are inevitably rotating and very, very quickly. We’ve got two methods that take advantage of this: the Penrose Process and the Blandford–Znajek Process, which allow much better than 6%, at more like 20 to 43% of mass energy conversion, partially by robbing energy off the black hole from its ergosphere, which incidentally isn’t a sphere. We will not delve into that today, beyond noting that ergospheres, are messed up regions of spacetime above the event horizon created by rotation from which you can extract way more energy than you could by skimming over the event horizon of a non-rotating black hole. You could never plausibly take a spaceship into the ergosphere of a typical solar mass black hole and bring anything living out, even for the more extreme definitions of ‘living’ we use on the channel. But you can extract energy and we think it is what powers quasars, those enormously energetic events we see in distant galaxies which we believe to be accretion disks of supermassive black holes. Given that a quasar is usually pumping out thousands of times more energy than an entire galaxy, you can see why a scaled down version of this makes a nice power plant. However, these approaches, while they can be used for moving ships, mostly do so by otherwise mundane methods, acting as a power source for matter or energy beams to push ships or a gravity well for slingshotting. The exception to this is turning it directly into an engine of a truly enormous ship, which I will go ahead and name a quasar drive, and we’ll talk about that and why you’d do that more in two weeks in Fleet of Stars. Channel regulars are probably already assuming we’ll be moving on to hawking radiation next, since these big black holes are obviously not ideal for regular size spaceships, but there’s a very large mass gap between natural black holes and the kind we’d want to use for Hawking drives, and trying to make black holes in that range and use their power is tricky, maybe impossible, so let’s consider scaling our quasar drive down a bit first instead. To make a black hole you just need to get a bunch of mass or energy in one spot at a density high enough that it would be inside its own event horizon. This can potentially be done several ways. The conceptually simplest is to replicate nature, build yourself a great big ball of iron and wrap that sucker in H-bombs and implode it. The second would be to slam two such bodies together at very high speed, amusingly a similar process to how the gun-type nuke works, and also mimicking nature a bit here too, as colliding neutron stars are thought to produce black holes, not to mention earthloads of gold and other heavy metals. We’ve discussed the concept of a Relativistic Kill Missile here before, a plain old hunk of metal accelerated to relativistic speeds, usually by turning huge stellasers on them to push them up to speed. One way to make a black hole would be to have two star systems with laser pushing devices shoving a pair of RKM’s up to enormous speed which then slam into each other, and since a RKM need not be a simple metal slug but could have some computers, propellant, and guidance on it, such a terminal rendezvous should be doable. Indeed, you could probably time things to have a whole bunch slam together at once. An RKM potentially carries many times more kinetic energy than its mass energy too, and as mentioned, it’s really energy, not specifically mass, that matters for gravity. A black hole event horizon has a radius or diameter linear to its mass, double the mass, double the width, so it’s actually easier to make bigger ones than smaller ones because you don’t need as high a density. For Hawking Radiation driven ships, these really are only useful in the low megaton range and preferably kilotons, and we’ll explain why in a moment, but while that seems great for a ship, practically ideal, there’s no guarantee we could make let alone refuel such a black hole, so a much bigger artificial black hole, but still a relatively tiny one, might be all we can do. There’s no real technological hurdles to making an artificial black hole by implosion or collision, it’s just brute force. Ramming two big trillion ton iron spikes into each other at 99.9% of light speed is no easy task, but requires no new physics to do it. You make the smallest black hole you can, then feed it matter and grow it if you need to, because this method of black hole power generation benefits from size and is about feeding the black hole. Your feed mechanism then also doubles as your attachment for keeping your ship tied to the black hole. Black holes respond to force same as anything else does, you just don’t want to shove on it with your hand or anything else you want back, so your ship is basically being pulled toward the black hole, and you use the matter beam feeding it to shove you away from it, and everything involved here is ionized and carrying a charge so you can use magnetics to direct things. I want to emphasize though, these are BIG ships, even by this channel’s standards. Hardly the biggest ships we’ve discussed or will discuss but we’re not talking the Millenium Falcon or Firefly here, or even the Enterprise. You only go this route if you can’t make black holes less than a megaton, which is already ten times more massive than an aircraft carrier and would just be the drive. If the smallest black hole you can make this way is a billion tons, then your ship and black hole fuel presumably mass in that range too, and now you’re talking about something O’Neill Cylinder-sized. If the smallest you can make and feed is one with a nanometer radius, just a bit bigger than an atom, so you can cram atoms into it, then you’re looking at ships massing around a quadrillion tons, which are likely to be Death Star sized objects, or if more long and skinny, dozens of kilometers across and hundreds long, assuming a density just short of water. However, we do have a couple other ways to pack matter in tight. One example is dark matter, which to the best of our currently limited knowledge only interacts via gravity, so if you can find another way to interact with it, and move it about, you could potentially pack the stuff in absurdly tight without having to worry about it slamming together to heat stuff or fusing. Incidentally, dark matter would just tend to buzz around a black hole only falling in when it actually rammed the event horizon. Needless to say, we currently have no idea how to manipulate dark matter or even what it is for sure, indeed micro-black holes left over from the big bang is one of the candidates for dark matter, but if we ever figure out how to manipulate it, employing it for gravity and mass is one possible usage. However, we have other particles that don’t mind being close to each other or indeed occupying the exact same spot; these are called bosons. Examples include the Higgs Boson, the gluons that glue quarks together, the Z and W bosons that mediate the weak nuclear force, and photons. Photons are lightwaves and even a laser pointer can make, aim and focus them, so this really is old school technology. Much more precisely aimed photons become much more handy than using them in a Powerpoint presentation. So the notion would be to make a huge laser and mirror array that lets us dump a huge number of them into the same spot at the same time. This creates a Kugelblitz black hole. It’s what lets us seriously contemplate making black holes down beneath the megaton range that would produce a lot of hawking radiation. Needless to say, this likely requires a huge power source like a star to get all that energy together and an awful lot of mirrors to keep it all bouncing and focused. Light moves rather fast so if you’re trying to make something smaller than an atomic nucleus, which light would fly by in a mere billionth of a trillionth of a second, you need a lot of juice and a lot of precision. This is where we get into Hawking Radiation, because other methods all involve big and massive ships or infrastructure and generally need to be bigger and more massive to produce more energy, and often grow in mass as you produce energy. Hawking Radiation is the reverse, the less massive it is, the more power it gives off. It falls off with the square of mass, half the mass, four times the power, make it ten times more massive, get only a hundredth the power. Lifetimes go with the cube of mass, ten times more massive, a thousand times longer lived, as they evaporate slower and have more to evaporate. Your typical natural black hole gives off so little Hawking Radiation that you’d have problems detecting it even with our best equipment. Natural black holes are expected to live nearly forever. That Hawking Radiation is why it is ‘nearly’ forever. We’ve got two common explanations for this, the Virtual Particle explanation and the classical Hawking explanation which is similar to the Unruh Effect. Most of us find the virtual particle explanation easier to give folks, but it really isn’t ideal, virtual particles are always a bit dubious as an explanatory tool anyway and always leave folks wondering why the negative mass ones are the ones that fall into the black hole. Still it is the one I’ve used in the past for discussing the matter mostly because I hadn’t heard any other examples I felt didn’t require a heavy familiarity with special or even general relativity to make sense, and we’re really only interested in how much power these things produce. Last year PBS Spacetime did a really good explanation of Hawking Radiation and of the Unruh Effect not long after, so I’ll link that instead for today. For our purposes what matters is that black holes are theorized to produce a lot of power when they are tiny, again falling off with the square of mass. I will also link Viktor Toth’s Hawking Radiation Calculator, based off Jim Wisniewski’s one a lot of us use to save time, though there’s always some debate about Hawking Radiation values as we’ve no solid model for quantum gravity which certainly matters when you’re packing a black hole’s large mass into an horizon that’s quantum-sized. Using that method, a 1 megaton black hole would emit 356 Terawatts of power and live 2665 years, slowly evaporating mass and also growing brighter as it did. One ten times as massive, 10 megatons, would give off a hundredth of that, 3.56 Terawatts, and live a thousand times longer, 2.7 million years. One a tenth the mass, 100 kilotons, would give off a hundred times the power, 35.6 Petawatts, and live a thousandth the time, just 2.7 years. Needless to say, if you can feed them matter as fast as they expel it as energy, they will keep emitting power at the same rate and never evaporate. For that 100 kiloton one, you need to feed it about 396 grams a second or 34 tons of matter a day, any matter you can stuff down its tiny gullet. The megaton one would need a hundredth of that, 34 kilograms a day, and the 10 megaton a mere 340 grams a day, not bad considering this big weak one puts out 2000 times more power than the Hoover Dam for power output. If you can’t feed them mass, which is dubious because you can make them, that’s still a very long-lived battery you’ve got there. One important reason why it might end up being a battery is if the process for making it is wasteful. Grasers, basically lasers operating in the very small wavelength gamma ray frequency band, would be the best candidates to create these kugelblitz black holes and they don’t currently exist. So, we have no idea what their efficiencies would be or what energy source we could use to run a graser. If it turns out we need fission or solar power, that could limit the black hole to being a battery as creating it could be less energy efficient than powering the ship using a conventional reactor generator. Until we actually build a graser and a kugelblitz black hole, we have little idea of what the feeding of the black hole will entail or its efficiencies. Incidentally, since someone always asks why I tend to give black holes in tons not kilograms or pounds, it’s mostly the same reason I do it for spaceships or space stations, normal seagoing craft are usually discussed in their tonnage and scifi tends to ape that, thus so do I, and since we’re talking about it as a ship component usually, values get given in metric tons. Plus I think the kilogram is a stupid basic unit. Battery or generator, there’s a lot of ways to use the kugelblitz black hole’s power to run a spaceship’s engine, but if you happen to have something reflective to gamma-rays, which we don’t yet, you can just spit it all out the back as a giant photon drive, and if we use the megaton example, and assume nothing but near weightless ship around it, that thing would experience .12 gees of thrust, or 10 milligee if we assumed the whole ship, black hole included, weighed 12 megatons, or about 120 aircraft carriers. Okay, that doesn’t sound fast, but like an ion drive it’s not that it has a lot of thrust it’s that it will keep it up a long time. Now, we could boost that by the same method we could run the thing if we didn’t have gamma-reflective materials, which is by dumping gas in around it to soak up the gamma rays and get hot and ionized and shoved out the back. But that is paying a mass penalty, as you will run out of fuel much faster than if you crammed it into that black hole. Incidentally it is not sucking any or much of that gas in itself, because it is smaller than an atom and emitting a lot of energy. So it’s like trying to cram a basketball into a spewing garden hose nozzle. Now the 10 megaton version produces a hundredth the power and has 10 times the mass to push around, a thousandth the acceleration. While the 100 kiloton version is emitting 100 times the power and has a tenth the mass, so we’re getting a thousand times the acceleration out of it. You will also see much higher figures for power output in this mass range in some discussions, like I mentioned there’s debate about models and I’m opting to use the one with the handy calculator available online because I know my audience and many will want to put in their own values. Kicking it down to 10 kilotons of black hole and that same ratio of ship, you’ve got 10,000 times the power of the 1 megaton black hole pushing a hundredth the mass, a million times more acceleration, but your black hole would only live a single day unless fed and would be emitting about 15 times as much power as hits the Earth from the Sun, as a giant gamma beam out the back side, just as a reminder of why we say there’s no such thing as an unarmed spaceship and why space travel is very energy expensive, since you could light several planets up with that much power, instead of pushing a few thousand folks around. Again depending on models each tends to have a sweetspot for the ideal mass of a black hole as a ship drive, and it always depends on if you can feed the thing, and whether you can do the straight photon drive. If you can feed it, you can also just add more smaller black holes to up your power output for a bigger ship, need twice the power, slap in two black holes, if you can’t do a smaller one or it’s not practical to feed it matter. They’re great for efficiency and high maximum speed anyway, as they match antimatter for mass-energy, and even if you lose a lot of that by using mass superheated by absorbing the gamma it gives off as your thrust, it still beats a fusion drive and that version is easy to throttle. Get a megaton one and you’ve got a power source that’s quite good compared to a fusion drive. Even adding propellant to get that higher thrust, and that will last you millennia, you just have to refill on propellant occasionally and literally anything works, and if your fuel storage gets ruptured, you can still slow down the slow way. Even without a gamma-reflective material, you can make a large containment chamber and let that heat up to produce radiation in wavelengths you can reflect. That’s the same trick we discussed using for making black holes into fake suns earlier this year. Plus, unlike antimatter, they don’t explode, or at least do so at a set and easily calculable time. Since they are subject to the rocket equation, they do not quite match a laser-pushed system, which also gets to double up by bouncing light off a ship not just emitting it. However, you can use them to power those lasers far more efficiently than a star or fusion reactor will, assuming you can make larger stationary ones you can feed, an unfeedable black hole is just a battery, not a generator, though that’s often handy too. The big problem with laser highways is that you are dependent on that beam. Someone can shut it off, and there are problems keeping it on target especially at long distances, so you get back that freedom of being able to steer your ship wherever you want when you want. They work great in combination with laser highways too, same as we discussed for a fusion economy in Colonizing Neptune, you use the beams when you can and the engine when you want, and you can get up to a very decent fraction of light speed this way, such a ship ought to be able to pull off half-light speed, depending on what you’re carrying and how efficient your setup is and if you’ve got help speeding up or slowing down. A black hole based ship though, of any of these varieties we’ve discussed today, is but the tip of the iceberg that a black hole economy and civilization offer, if we can master them and if our theories about them are mostly correct. And we’ll be looking at them in more detail in the coming episodes, so stay tuned… So I get asked fairly frequently about a lot of the graphics we have on the channel these days and a great number of those are done in-house by various animators and graphic designers who volunteer their time to bring these awesome ideas to life. Indeed that’s part of the reason we revisited the topic of black hole ships, as the original video only had animations I’d done and my talent for that, especially back then, was nowhere near as good as what they produce. Needless to say I can’t thank them enough and you can always see more of their work by clicking on the links to their various art pages down in the video description, where we always list the editors and musicians who help on the show too, and if you’ve an interest and time to volunteer helping out, we’re always glad to add to our numbers and I’d also always encourage more folks to try their hand at making their own YouTube videos. Animations and graphic design take practice to get real good at, but it doesn’t take too much to get started and if it’s something you’ve an interest in learning, it is topic that there are a lot of top notch courses for over at Skillshare. I’d particularly recommend PolyMatter’s “How to Make an Animated YouTube Videoâ€, since Evan starts at the beginning and walks you through how to do an entire video and how to do it without buying lots of expensive software or hardware. And that includes learning to do it, because you can join Skillshare for 2 months for free, and have access to that and many other courses on graphic design or browse from over 20,000 courses on a host of other useful topics. Skillshare is an online learning community with over 20,000 classes covering everything from practical daily skills to things like programming, writing, or science. A Premium Membership gives you unlimited access to high quality classes on must-know topics, so you can improve your skills, unlock new opportunities, and do the work you love. Join the millions of students already learning on Skillshare today with a special offer just for my listeners: Get 2 months of Skillshare for free. To sign up, visit the link in the description and the first 500 visitors get 2 months of unlimited access to over 20,000 classes for free. Act now for this special offer, and start learning today. So as mentioned, we’ll be looking at Colonizing Black Holes in three weeks, and dig more into a lot of terraforming and industrial application black holes might have. Next week though, we’ll be returning to the Upward Bound Series for Sky Platforms, and look at some of the launch concepts for getting into space by starting off already high up in the sky. And two weeks from now, we’ll be back to this series to look at the possibility of using entire stars or whole fleets of them for colonizing the Universe and reshaping our galaxy, or even our whole Supercluster, in Fleet of Stars. For alerts when those and other episodes come out, make sure to subscribe to the channel, and if you enjoyed this episode, please like it and share it with others. Until next time, thanks for watching, and have a Great Week! So today we are looking at using small, artificially created black holes as a way of powering interstellar spaceships and we started on that last week by discussing the properties of micro-black holes and Hawking Radiation. If you haven’t seen that video, unless you happen to be very familiar with how Hawking Radiation works, you might want to click the video link on the screen and catch that first. Like all the video links on this channel, doing so will just pause this video and open that video in a new window. But the thirty second summary of that video is that smaller black holes emit a lot of energy, which we call Hawking Radiation, and the power released by a given black hole roughly scales up inverse-square with its mass. Meaning that if you have two black holes, one twice as heavy as the other, the bigger one gives off only a quarter of the power the smaller ones does, and since they are emitting this energy by evaporating their own mass till they run out, the bigger one will live eight times long, since it emits only a quarter the energy and has twice as much mass to fuel that emission. Similarly a black of only a tenth of the mass will emit a hundred times the power, but with only a tenth the mass will run of fuel a thousand times quicker. I should note that this is just an approximation, not an exact calculation. Since the black holes we can detect are so massive they don’t put out enough Hawking Radiation to power a tiny LED light we couldn’t measure their Hawking Radiation if they were even as close as our own Moon, let alone hundreds of light years away. So we have only theoretical models and those don’t actually exactly follow the inverse-square mass relationship I just mentioned anyway, and there are competing models. So today I’ll specifically be using the values from Westmoreland and Crane’s 2009 paper originally discussing Black Hole Starships, since it is the one you will most likely hear referenced if you decide to do some more personal research on this subject, and a link to that paper is included in the video description below. That said, the core concept for the ship then is pretty straight-forward. You make a small black hole, one with a mass somewhere between an aircraft carrier and a small fleet of oil supertankers. Once you have a black hole of that size you have an object emitting a huge amount of power, the ones we’ll be looking at today emit power somewhere between a percent or so of what the Sun hits the Earth with to several times what the sun hits the Earth with. That figure incidentally is usually given as a couple hundred petawatts, and a petawatt is a million gigawatts, where most big nuclear reactors and hydroelectric dams produce about a gigawatt, so Earth’s solar power supply is on an order of a hundred million times larger than our biggest power plants produce and the black holes we’re looking at today produce power comparable to that, millions to billions of times more powerful than our largest power plants. I’ve mentioned in the past that the concept of an ‘unarmed spaceship’ is an oxymoron, that the sci-fi staple of an unarmed freighter getting attacked just isn’t plausible, and this is another example of that. The sheer power output of any interstellar spaceship is truly immense, and a petawatt is the equivalent power output of 16 Hiroshima nuclear bombs going off every second. The ships we’ll be talking about today operate anywhere between 1 petawatt to several thousand petawatts. So even the lowest powered of these ships, even if you could only effectively direct 1% of that output as a weapon, could blast a large city into rubble every few minutes, while the higher power versions operating at highest efficiency could effectively wreak havoc as though they had a machine gun that shot Hydrogen bombs. That’s without even directly weaponizing a black hole either, which we’ll discuss near the end of the video, that’s simple recognition that if you have that much power you can do a lot of damage. Now that power is omnidirectional in its output when emitted, same as a star, and you can generate thrust by putting a mirror up on one side, so light flying out in the wrong direction reflects back in the right direction and the radiation is no longer omnidirectional. You can do even better with a parabolic dish. That’s your simplest black hole drive, conceptually anyway, a black hole with an attached parabolic dish. You stick the rest of your ship on the other side of the dish, and it turns out black holes in around the megaton range with attached ships of similar mass can pull off accelerations and maximum speeds that can get you from one star to a neighboring one is less than a human lifetime and let you wander around solar systems, even the deeper darker outer zones, in timelines of months. In the case of Black Hole Ships, the key figure, if things are running very efficiently, is that you get one-gee of acceleration on a one megaton total mass ship for every 3000 petawatts of power you have. As huge as the power output sounds, it still isn’t terribly impressive when it comes to shoving things up to the speed of light. The table I’m bringing up is an extraction of the calculated power outputs, in petawatts, of various black holes by their mass in megatons that was discussed in Westmoreland and Crane’s 2009 paper. I’ve gone ahead and added to that the Power to Mass ratio, as well as what the acceleration, in gees, of a spaceship would be that had equal mass of black hole to the ship and its cargo. So a two megaton ship would be half black hole by mass and half ship and cargo. Lastly I’ve added in a column for how long it would take for that ship to get to just 1% of light speed. Which I picked strictly to be able to avoid relativistic effects, since its minimal at that point. At 1% of the speed of light your clocks will lose only a few seconds a day in terms of time dilation and good-old fashioned Newtonian equations for velocity and kinetic energy would only be inaccurate with high precision measurements. Now that would imply an obvious preference, you want the lightest black hole since it gives the best acceleration, and sure you don’t want eight-and-a-half gees, but just as we could almost double that acceleration if we could strip the ship mass down to near zero besides the black hole, we can slow it down by adding more mass. The problem is, as I’ve mentioned, that small black holes don’t live long and the smaller they are, the shorter their life. So the last column is the approximate rounded lifetimes of the black holes as listed in the original paper. So unless you can find some way to refuel your black hole, by dumping more mass into it for instance, these smallest black holes won’t last long enough to get you to your destination. As they put out energy they lose mass, which causes them to emit energy even faster, and lose mass faster, until eventually they are so small and high powered that they essentially explode. So if your black isn’t massive enough to survive your trip you eventually need to jettison it and now you have no power source to slow back down with when you reach your destination. Which isn’t necessarily a problem, we discussed in the Interstellar Colonization video some of the tricks you can use to slow a spaceship down without using fuel. One of those is the Bussard Ramjet, a concept for a spaceship that ran by magnetically sucking in interstellar hydrogen gas and ramming it down the axis of the ship to produce fusion and thrust. This concept turns out not to work because when we could run the calculations better we found that all that gas, which is essentially stationary to interstellar space, would slow the ship down more by being absorbed then it would produce. Which was unfortunate but had the silver lining that even though you can’t accelerate with it, you can use it to slow down for free. So if you have a short-lived black hole accelerate your ship up to cruising speed you could then slow down at your destination this way, and power yourself during the trip more conventionally with a nuclear reactor, fusion if you have that, or otherwise classic fission, as life support is only a tiny fraction of the energy budget for an interstellar trip at relativistic speeds. Of course another possible use of that magnetic ramscoop method might be to suck in matter and jam it into your black hole to refuel it. This doesn’t give you infinite acceleration, since eventually you will reach a speed where even the near-total conversion of mass-to-energy by that black hole won’t match the lost momentum of sucking in that relatively slow gas, but it gets you a very high speed and lets you keep your black hole. But refueling a black hole is easier said than done and the smaller the black hole, the harder the refueling. I mentioned in the last video that refueling a small black hole is much harder than making one in the first place. In that we suggested the best way to make one would probably be with tons of lasers all pumping energy into the exact same place at the same time, a place much smaller than the nucleus of an atom. This concept is called a Kugelblitz black hole, Kugelblitz just being ‘ball lightning’ in German, since you a making a tiny little ball of light. Light, being made of photons, doesn’t have a problem being squeezed together like normal matter does so it’s easier to make black holes out of. A kugelbltiz black hole is hard to do simply because it requires immense energy and precision. If you try to do it with normal matter instead, like interstellar hydrogen, you are trying to jam materials together to pressures and temperatures far beyond what is necessary for fusion it’s very improbable we’d find a way to do that especially without spending more energy than we put in. Same problem, you can’t refuel a black hole on your ship with lasers since you’d burn more energy up making those lasers than you’d get out of it. And the smaller the black hole the harder it is to do, with normal matter, since you are trying to squish that matter into an even smaller spot and fighting against even higher power output resisting that matter input. The analogy I used last time was that it was like trying to shove a beachball down the nozzle of a firehose that’s turned on. Making them, the kugelblitz way, is essentially the process of having a massive swarm of power collectors that fire lasers with high precision at one spot at one moment, allowing you to use a star as a black hole generator for spaceships. That requires ludicrous levels of precision and vastly huge solar collectors but that doesn’t appear to break any known laws of physics, refueling with random hydrogen probably does, so midtrip refueling is probably not an option. We also have the problem that black holes emit very high powered particles, like gamma rays, making them very hard to reflect the power from, so you can’t just wrap a black hole with a highly reflective material to bounce the emission back in to the black hole to be reabsorbed. At this time we lack any materials that acts as good mirrors to gamma radiation. If we did have one it would make things a lot easier since you could create a throttle that let you bounce some of the emitted energy back into the black hole, decreasing its net power output and extending its life, when you wanted to do so. Also without anything that can reflect gamma radiation you have to absorb all that gamma radiation as it emerges from the black hole and let it heat up a material to just below its melting temperature. So you place a sphere, or hemisphere, around the black hole. It glows red hot and emits normal light, which can be reflected by a parabolic dish. I’ll refer to this as an absorption shell. Unfortunately the more power you have, the bigger your absorption shell needs to be. Tungsten, the element with the highest known melting temperature, about 3700 Kelvin, can radiate about ten megawatts per square meter without melting. Twenty since it can emit from both sides. That still means that you need about 50 million square meters of the stuff for every petawatt of power you want to absorb. Now the good news is there are some new alloys with even higher melting points than Tungsten, and blackbody radiation goes with the fourth power of temperature in Kelvin, so if we found an alloy that had twice the melting point of Tungsten it could radiate 16 times as much power without melting. But even then you’d still need a few square kilometers of absorption shell to handle all that energy. Now these are massive ships weighing at least hundreds of thousands of tons if not millions of tons, so you can get away with absorption shells that big, especially since the shell needn’t be terribly thick. However that raises yet another problem, and that is how you can keep the black hole tied to the ship. The black hole is emitting its energy omnidirectionally, so it’s not accelerating itself at all, and your ship will just fly off leaving the black hole behind. You can hardly attach a rope to the black hole since it is smaller than an atom and will flat out shred anything it touches even if it didn’t melt it apart first. Now a number of methods are possible, such as giving the black hole an electric charge and binding it to the absorption shell that way. The absorption shell can be leashed to the ship conventionally by some struts connecting it to the parabolic dish. That may or may not work, but to prove it is possible, the conceptually easiest is just to use the black hole’s own gravity to hold on to the absorption shell while it’s radiation pushes it away. This usually known as a gravity tractor, and it’s a lot like the Statites or Shkadov thruster we’ve discussed in the past. Something hangs above a radiant object, pushed away by that radiation, but pulled on by its gravity. The hard part about doing this with a black hole, a small black hole, is that they don’t actually have that much gravity but do have an awful lot of power output, so getting close enough to the black hole to be gravitationally bound to it means you are sucking up even more radiation. Just as an example, for a one megaton black hole, the distance at which it pulls someone with the same force as Earth pulls on you is about an inch. Meaning you’d need your absorption shell, and overall the majority of your ships mass, only an inch away to get one gravity of tug on the ship. At that distance the power being absorbed would obviously melt any material but even if it didn’t the radiation pressure would fling it away at more than one gee. For bigger, longer-lived, lower-powered black holes that radiation pressure drops off a lot and that gravity ramps up a lot, so you could use gravity to leash a bigger black hole for use as a ship drive but there wouldn’t seem much point except maybe for intergalactic travel, because it would simply take way too long to accelerate everything. But I offer that just as a way of explaining how you can leash a black hole to a moving object in a way that’s simple to understand and definitely works. Ideally, if the technology emerges to reflect gamma rays, and we do have some tricks for doing that which are improving, and if you can feed matter into a black hole, you could set up some particle beams shoving matter into the black hole from behind, and giving it forward momentum and refueling it, then have the gamma reflective material helping cut down on your absorption shell size, or simply letting you discard the absorption shell in favor of just the parabolic reflector dish able to reflect gamma rays. That’s probably the key piece of technology to make such a system genuinely viable, we might be able to do without it and still use the concept, but ability to make a material that reflected gamma rays as cleanly as a normal mirror reflects visual light makes this technology vastly less cumbersome. If you also had the ability to beam hydrogen you picked up along the way into the black hole, to refuel it and help push it to keep it in place its even easier. With such a setup you would have a ship able to get pretty close to the speed of light, do so in a reasonable period of time, and run indefinitely off the fuel just lying around in the interstellar void. Your maximum speed with such a setup wouldn’t be infinite, even ignoring the speed of light, since you’d eventually reach a point where the matter you were sucking in was slowing you down by the same amount as the power it produced would speed you up, but that would be quite high. If you don’t have those options you really need to use larger sized black holes unable to produce accelerations of one-gee, but even if you did you’d probably never build a ship that produced much more than one-gee of acceleration, that would get uncomfortable for the crew so even if you had a very small and powerful black hole you could refuel and contain you’d probably just have a much larger over all ship. The values I gave on the table just assume the total ship and cargo not including the black hole had the same mass as the black hole, to keep it mentally easy, but if you’ve got a black hole that would produce 10 gees of acceleration on its own mass, you could simply have a ship that weighed 10 times as much as the black hole, including the black hole, so that it was 10% of the mass, pushing the ship at one-gee. In such a setup the ship is basically a skyscraper with the black hole in the basement, rather than having any rotating sections to provide artificial spin gravity. That’s usually our ideal ship for people anyway, one able to accelerate at one gee. Without the ability to refuel one and reflect gamma rays you can never have that, and frankly I don’t think black hole powered ships could ever be viable without at least one of those technologies. Before we close out let’s talk about two other things. First, the impact with SETI, and second the ability to weaponize these things. We’ve talked a lot on this channel about the Fermi Paradox, the question of where all the aliens are hanging out, and SETI, the Search for Extraterrestial Intelligence, is the effort to answer that, either by finding them or showing they don’t exist. One of the ways we do that is to listen for radio chatter, but the more advanced concepts always involve trying to figure out what technologies they have and how we might see the byproducts of those technologies. For instance if the aliens are making Kugelblitz black holes you’d expect to see stars with large solar collector swarms dwarfing planet in sheer area. You’d also expect to be able to pick these things up from their gamma radiation or emitted gravitational waves or gravitons if gravitons exist. We don’t have detectors at this time hunting for such emissions but they would be one more weapon in the arsenal for SETI hunting. Speaking of weapons, there are few obvious ways to weaponize a black hole. None of those involve just dumping a black hole onto a planet for it to eat the planet up, I explained why that wouldn’t work in the previous video. Your first and simplest one would just be to crash a black hole starship into the target. A megaton of relativistic mass would unleash nearly as much power as a star emits in a second when it hit, something akin to a billion h-bombs. This isn’t as threatening as you might initially expect since if you saw the ship coming you could vaporize it, and while the black hole would still be there it would just fly right through the planet without doing much damage and continue to sail on till it evaporated. Of course when these things do evaporate the unleash quite a lot of energy, somewhere around 10^24 joules in their last second of life. And you can control their initial speed and direction when making them so if you can make on the fly and aim it at the right place and time it will explode pretty impressively. That’s not a covert and subtle weapon though, since they glow very brightly, especially near the end of their life, but you couldn’t shoot one down either, at best if you could measure its position and speed with great accuracy you might be able to hit it with a beam, just like you were refueling it, and shove it off course. If you can’t hit it off course that target is dead unless it can move out of the way in time. Of course a ship and probably even a bulky space station probably could see it in time and move, and while these would seriously damage a planet’s surface they aren’t anything like powerful enough to blow up a planet. Excellent bunker buster though, since it will sail through anything unimpeded. If you’ve got the gamma-ray reflective materials and can refuel the things, implying you could knock one of course, then you can probably also make them on board a ship. And you could make very small ones inside what would amount to a missile with a very high acceleration and maneuverability and just cut off the fuel at a time to make it explode when it arrived. That would be fairly hard to detect since it would be small and emitting almost all its detectable radiation behind it, where the target can’t see it well. So if you’ve got the ability to reflect gamma rays and also feed raw matter into small black holes a black hole missile would be pretty devastating, even if you vaporize the missile, which would have enormous kinetic energy, if the timing on the fuel was done right you’d still get that black hole explosion, and that would be very hard to avoid since the things would be hard to see and highly maneuverable. So black hole starships are probably limited to the land of science fiction for a while but show real promise especially if we get a couple fairly plausible technologies down the road. Next time we’ll be looking at some stuff that’s more implausible when we look at various concepts for Faster Than Light Travel and Communication. If you want to be alerted when that video comes out, make sure to subscribe to the channel, and this week we also have a poll again for the next subject we’ll be covering after FTL so make sure to take that. As always, comments, questions, and video suggestions are welcome, if you enjoyed this video hit the like button, share the video with others, and try out some of the other videos on the channel. Thanks for watching, and have a great day! This episode is sponsored by Brilliant Probably one of the most paradigm-shifting concepts leading into the modern era of science is that we are not special or terribly unique here on Earth, but merely one fairly hum-drum species on a mediocre world among the countless trillions in the void… but what if that’s the wrong perspective? So today we’ll be looking at Boltzmann Brains, the Anthropic Principle, the Simulation Hypothesis, and Consciousness. This is part 2 of a collaboration with Jade from Up and Atom, so if you’re coming over from her channel, welcome, and for channel regulars, you should watch part 1 on her channel first, where the Boltzmann Brain gets explained, then watch this one, and you can find part 1 linked in the video description or the in-video card. Quick summary version though, improbable but possible events will tend to happen given enough time or space. Flip a coin enough times and you’ll get heads ten times in a row, shuffle a deck of cards enough times and in spite of randomizing it each shuffle, you’ll return it to some more ordered state eventually, like all the cards in numerical order. Look at enough collections of matter and you’ll find something that’s randomly assembled into a seemingly artificial grouping, like the basic building blocks of proto-life, or a computer chip or a brain or even an entire galaxy. Needless to say, things which are less improbable will be more likely to occur and should be more frequent, and in Ludwig Boltzmann’s time, the late 19th century, we assumed the Universe was probably an infinite and eternal place in which anything which could happen should happen, though again the more likely it was to happen the more often we’d see it. Thus a randomly assembled brain would be more common than a randomly assembled galaxy. Or a randomly assembled Universe, which is a notion still often kicked around as a possible cause for our own Universe appearing in a Big Bang, a low entropy state slowly rising in entropy as the Universe expand and decays. The thought that perhaps our Universe simply emerged from some random fluctuation, not very different than shuffling a deck of cards back into order, though vastly more improbable.[a][b] We examine this notion more in part 1, and our main interest now is in considering some of the possibilities it implies. To look at those we first have to consider the Anthropic Principle, which is itself a fairly difficult concept to cover for a variety of reasons. First it is a somewhat tricky concept. Second, the popular examples people use tend to really predispose people to dislike the solutions, and thus the method of reasoning. And third, there’s no rigorous definition of what it is. In a way, it’s not a tricky concept at all, it’s basically the exact opposite of the Copernican or Mediocrity Principle, and is an example of a starting point you use for looking at situations when you have virtually no evidence to work with and no obvious way of getting more anytime soon. Its examples tend to include cases where it’s basically impossible to get more data at this time too, which results in examples that set many people’s teeth on edge in my experience. What is the Mediocrity Principle? Well you know that one, it’s a cornerstone of science. If we have only one or only a few examples of something, we choose to assume they’re pretty normal examples until we have evidence otherwise. Often they aren’t normal, but it helps to start from this case. Hence we tend to assume Earth or Humans are fairly common examples of habitable planets or technological civilizations. Hence the Copernican Principle, Earth is not the center of the Universe and is probably fairly mundane, or mediocre, and thus the generalized version, the Mediocrity Principle. Of course often the first example of something we see is not particularly normal, and not just as an outlier of chance, that first alien you ever met was fairly tall or short for their species for instance. Someone watching Earth having come across it might catch our broadcasts of basketball games and assume humans were quite taller than our average. Frequently the first example of something you’re going to encounter is an outlier, not by chance, but for the reason you’re encountering them first. This is how we ended up dubbing our Sun a Yellow Dwarf originally, even though it’s much brighter and more massive than average, because it is far easier to see the more massive and bright stars so we thought they were normal first. What’s more, you can have cases where simply by being able to observe something you represent a skew on the normal. We’re not talking about normal observer bias here, but the kind where your odds of being there to see something are altered by you existing. Now this often sounds a bit arcane and many examples of it don’t help, but you think about problems this way all the time, same as the Mediocrity Principle. You routinely encounter stuff and figure it’s probably a mediocre and common example of that stuff till you get more examples. But you also assume you observing it is probably impacted by you, for instance it’s not going to surprise anyone watching this video if they go into the comments and see a lot of generally geeky comments on science, math, or science fiction and you are probably watching this, observing this, because you have such interests too. You might be here randomly but even then this probably got recommended to you because your prior watch and search habits indicated an interest along those lines. Not a random observer, and it affected what you could see. Same, if you woke up with amnesia in a room full of people wearing the same clothes, you could assume via the Mediocrity Principle that most people wore that garb, like business suits or t-shirt and jeans for instance, or you might assume you saw that first as an outlier appropriate to your observation, like doctors and nurses in scrubs as you had a head injury. Or you might glance down and notice you wore the same thing, like a jersey or military uniform, you banged your head doing drills and you are observing them in this garb because you, as an observer, are just much more likely to be in their particular company. These are all valid approaches to looking at situations when you have virtually no evidence on hand. Now I mentioned that another problem with the Anthropic Principle is that it doesn’t have an exact definition, one of the more famous thinkers on this topic, Nick Bostrom, noted around 30 fairly distinct versions when looking into the matter and added his own too, the Simulation Hypothesis, one familiar already to channel regulars. Another, and the one where the term was first used, was Brandon Carter’s Doomsday Argument, and this version often is called the Weak Anthropic Principle, though he’s since remarked that he wished he’d called it the Observer or Egocentric Principle instead, and as you’ve probably noted those are maybe better than the Anthropic Principle since they more generally speak to what it is, an assumption when looking at a situation that you’re not some random observer of an event that’s probably normal or mediocre as such events go, but are focused more on why you are seeing that event. We looked at the Doomsday Argument some years back and you can catch that episode for the details. The third well known version is the Fine-Tuned Universe theory, popularized by Cosmologists John Barrow and Frank Tipler in their book the Anthropic Cosmological Principle, and along with the Simulation Hypothesis are our two of interest in regard to Boltzmann Brains today. I mentioned that these examples often stir a bit of dislike and argument in folks when trying to learn the concept, and the reasons are pretty obvious, while the Doomsday argument, Simulation Hypothesis, and Fine-Tuned Universe theory are great examples for generating discussion of the topic since, they may be summed up in order as basically arguing Humanity is mathematically doomed, if Reality is actually real, and if there is a God. Shockingly these topics sometimes touch a nerve. For Simulation Hypothesis the reasoning is pretty simple, and often misstated in discussion of it, Simulation Hypothesis is not the idea that you might live in a false reality, but rather that you might live in a specific type, an Ancestor Simulation. Which is where the simulators are specifically running their own history or a version of it, like if we ran a simulation where a war ended differently or a piece of technology got invented sooner or later or more personally, if your parents had moved to a different town when you were young or so on. Those are ancestor simulations and one of the reasons that distinction is important is because it implies the rules of your reality actually match up to the layer above simulating it. It’s not very likely they’d have changed the basic rules of how the Universe operated, or maybe at most tweaked one a little bit, and so studying the Universe around you is actually helpful even though it’s fake. Maybe the Moon Landings happened a decade later and by a different country, but the Moon still orbits the Earth and for the same reasons. That’s not a requirement of a simulation, and if you’ve played games where you can walk off one side of the screen and pop out the other, that’s an example of playing with the basic physics, that Universe circles around on itself and isn’t a flat plane. More on that in a moment, and if you want more on the Simulation Hypothesis we’ve got episodes looking at it, but one key bit of it is the Principle of Indifference. Yeah, lots of Principles today. The Principle of Indifference, or Principle of Insufficient Reason, is another of those approaches to making guesses and decisions when you know basically nothing. You assume if you have a handful of options, all reasonably plausible, but without anything to let you argue decisively that one is more likely than another, you just assume for now that they are equally likely. For Simulation Hypothesis we assume 3 reasonable scenarios. First, that nobody does these ancestor simulations because they are impossible or you wipe yourself out before you can do them. Second, that nobody does them because they are impractical or undesirable or illegal, but that you can do them if you want, and third, that they can be done and get done a lot, so much so that the vast majority of 21st century Earth’s are actually Ancestor Simulations run from sometime ahead in the future. You’ll often be told odds about us being in a simulation or not, but by this reasoning, it’s 33%, or just under a third, because one third is option 1, the other third is option 2, and in option 3, even if there are many more simulations than real universes, there’s still a finite chance you’re in the real deal, so just under a third. Obviously those three options aren’t going to be equal in probability, but we have no way at this time of knowing what those odds actually are. Again see those episodes for further discussion. This of course is not the only type of simulated Universe you can do, you can change the fundamental physical rules, and presumably you could for instance set the speed of light in a simulated Universe to any value higher or lower than what ours is. There being an awful lot of numbers you basically have a vast number of unique potential universes you could generate this way, and there are other physical constants and parameters you could tweak too, either individually or in combination. Needless to say, there could also be a large number of other real universes with different physical properties too, one of the examples of the Multiverse notion. As best as we can tell – currently - there is no particular reason why the physical constants of our Universe are the values they are, so we assume they could have been different. And as best as we can tell most of these values do not allow intelligent life to arise via evolution. Higher gravity, stars form and burn out too quickly for planets to have time for evolution, that sort of thing. If this is the case, that these constants can be over a huge range, the overwhelmingly majority of which can’t have life in them, well, you’ve got a bit of problem. The Universe would seem to be fine-tuned for life. You can assume we just got lucky or you can assume no such thing, that the Universe is artificial, fine-tuned, divinely created or simulated, take your pick. The alternative is obvious by now, that this Universe is indeed improbable, but that there are a bunch of other ones, not just ours, and most are indeed dead but since nobody is there to observe them, their probability of existing is not puzzling anyone. There is no evidence supporting any of the options incidentally, and they’re all pretty logically coherent, so feel free to pick the one that suits your tastes. It’s very handy for discussing the concept of drawing conclusions and making decisions with very little data for that reason. Now, this basic analysis of Dead Universes is off the notion of life evolving from something pretty simple into something much more complex, and as we’ve noted, a Boltzmann Brain is statistically far less probable – in a Universe with our characteristics – than an evolving one should be. Other rules, other probabilities, and it’s very easy to come up with a Universe where as improbable as a Boltzmann Brian is, it’s still more likely than Darwin’s Approach because the latter just won’t work there, whereas Boltzmann Brains can pretty much work anywhere. You could have a place where an entire Universe blew into a supercomputer and the machinery and fuel to run it randomly as soon as the place cooled enough to operate. You could have one where gravity was just super weak and everything meandered around in a stew until falling into patterns, and only those really big and complex ones could really sustain themselves long enough to do anything. Even in some Universe where gravity is so strong virtually everything turns into black holes almost right away, black holes could be used as a switch and so you can create a computer that way and so over a long enough time line – and black holes live a long time – you might expect a Boltzmann Brain to emerge made of the things. Critical notion, these dead universes may out number universes like ours by so much that the number of Universes in which one has popped up exceeds the ones where it evolved.[c][d] So such minds might be far more numerous than seemingly natural ones like ours. As we noted though, the Simulation Hypothesis only focuses on Ancestor Simulations because you can still meaningfully talk about the higher simulating layer if you’re assuming it works on the same principles. Needless to say some mind that just popped out of nowhere, a new conscious surrounded by the empty waste of eternity, or living in utter sensory deprivation because it didn’t come with any eyes or ears, is not going to be simulating us as an ancestor simulation. Even if it knows about the Universe it lives in and the rules it has, which is hardly guaranteed, simulating 21st century Earth as part of its past clearly doesn’t work logically. Which would seem to end the idea except here we have some mind, essentially dreaming away in the void. Possibly it’s a more or less human mind, possibly it’s some giant megacomputer like a Matrioshka Brain. Either way, its sanity would seem rather dubious. We can’t really assume that just because it was born blind and deaf and alone it’s naturally okay with those circumstances. We have a conscious mind shaped by evolution – presumably – so all our abstract thinking had to make some sort of survival sense and requires a certain basic level of sanity in one’s natural environment, for a given value of sanity. It does not, it didn’t evolve, it doesn’t have any predators, but it has, by random luck, achieved consciousness. Ponder that for a moment or two and you can guess that this lone mind in the void is probably as mad as a hatter, if the randomly assembled brain was anything even vaguely like ours, which of course at least some would have to be by random luck. It would be very easy for something like that to dream up a reality – either a world of people or just you, and indeed the ‘just you’ option is a lot more likely since as we noted at the beginning, a smaller Boltzmann Brain, one just smart enough to be of human intellect, is way more probable than one that could do a whole simulated civilization or Universe. Though it’s worth noting such a mind need not be static and incapable of growth, just because it wasn’t evolved. The random luck that created it probably need to randomly give it fuel and repair options or it will be a pretty short-lived intellect, which might permit growth and mutation too.[e][f] Regardless, I doubt most of us really have to stretch our imagination too much to contemplate the notion that we might live in some world we dreamed up as a delusion. Incidentally it doesn’t actually matter that rules of this Universe would imply life was likely – since they’d presumably be self-rationalized anyway – or that the entire premise of this is based off assuming other universes exist that have different rules by having seen inconsistencies in our own, Fine-Tuning. Because the premise doesn’t come from that, ignoring that it’s an old idea, that we’re dreaming reality, it requires no empirical evidence to assume your universe has rules and that there may be other places with different rules. It merely requires you believe that there are rules to your reality, even if they are wrong or made up. Again it’s not an ancestor simulation, so we couldn’t assume the real rules were anything like what we saw, but that hardly prevents us considering that there may be other places with different rules. In the broadest sense, if any place can exist, then you’d have places like our apparent reality where life evolved just like we think it did, ones where human-level minds, while improbable, popped out of nowhere first because evolution couldn’t really work there, and ones where giant megaminds popped into being and dreamed us all up. Obviously hard to figure out which of these scenarios is more probable but none should be impossible so at a minimum we can’t rule out that there’s a finite probability you or I are actually in any of these versions. Boltzmann Brains dreaming up everyone and dreaming up rules too, without knowing either or forcing yourself to forget things, which would require you be really nuts, like some sort of person left on their own in a dark prison cell for years. If you haven’t already seen Part 1 you can check that out for a discussion of why a Boltzmann Brain, in spite of being very improbable in our Universe compared to evolved intelligence, might be fairly probable or even more probable in a grand multiverse sense of things. Alternatively, we can’t assume it is more improbable anyway since if we lived in one, or were one, our observations about this natural Universe mean nothing anyway, again, not an Ancestor Simulation. This, by the way, is why I often say the big question probably isn’t whether or not reality is real but if it actually matters if it is or we’re just being a bit arbitrary about what ‘real’ means. Anyway the most probable Boltzmann Brain would be a single simple intelligence, just one smart enough to think about such things as abstract concepts like this, and if you were one of those than you’d have to assume we’re made up voices in your head. … and you’d have to be crazy to dream this stuff up, right? A theme we’ve had in today episodes is that our common approach to modern science is to assume that all we witness is fairly random and ordinary, that our ability to observe it is coincidental. We talked today about how that’s not always the best approach, but it has generally been a very good way to go about learning how our world and the Universe in general function, and that’s been a very useful and profitable set of knowledge for humanity to acquire, as a group and individually. Understanding math and science is just plain handy, but it’s also a lot of fun to know and having fun while you learn it is also the best approach. If you want to learn more math and science, and have fun while you’re doing it, try out Brilliant. Their online interactive math, science, and computer science courses and daily challenges let you enhance your knowledge of math and science with easy to learn interactive methods from the comfort of your own home and at your own pace. To make it even easier, Brilliant now lets you download any of their dozens of interactive courses through the mobile app, and you'll be able to solve fascinating problems in math, science, and computer science no matter where you are, or how spotty your internet connection. If you’d like to learn more science, math, and computer science, go to brilliant.org/IsaacArthur and sign up for free. And also, the first 200 people that go to that link will get 20% off the annual Premium subscription, so you can solve all the daily challenges in the archives and access dozens of problem solving courses. We have our regular Thursday episode coming up, and for that we’ll be back in the Alien Civilization series to take a look at the general methods and motivations for an alien invasion, be it overt or covert, and try to reason why a hypothetical alien civ might or might not do such thing, in Invasive Aliens. Then we’ll have our usual end of the month livestream after to close out July before heading into August to look at some examples of other threats to Interplanetary or Interstellar Civilizations, from natural to artificial, internal or external or existential. For alerts when those and other episodes come out, make sure to subscribe to the channel and hit the notifications bell. And if you enjoyed this episode, hit the like button and share it with others. And don’t forget to check out part 1 over on Jade’s channel, Up and Atom, or any of her other awesome episodes. Until next time, thanks for watching, and have a Great Week! So far, no technology exists that can control what we believe. Or so we believe... So our topic today is brainwashing and mind control, and we’re going to look at some of the technologies that might be used for it or to defend against it, but we’ll also be looking at some of the implications this might have on civilizations far away in space and time. Mind Control scares us for the obvious reason that it’s an invasion of the most extreme and revolting nature; but it’s also so frightening because politically and scientifically speaking, it’s also so plausible. We don’t really go through life fearing that murder or theft will be legalized in the future, but fear of a society in which everyone has been brainwashed is one of the most common themes of science fiction. Why? In part because it’s something we already have to deal with constantly. Simply by existing in society we are constantly subject to attempts to manipulate, sway, or indoctrinate us. Some level of it is necessary because children need to be educated in proper behavior not just academic knowledge. But we know all too well that privacy and freedom can be eroded away for even apparently benevolent reasons, and we know there’s no shortage of non-benevolent folks too. So we could end up with a dystopian nightmare, again something common in science fiction and nowhere better done than in George Orwell’s novel “1984â€, a terrifying story set in a dystopia of constant surveillance and indoctrination. Not many scifi novels have such a huge impact that they make a permanent impression on society, but even 70 years after its publication, a reference to 1984 or the term “Orwellian†or “Big Brother†brings an image of utter totalitarian control to mind, regardless of whether or not one has read the book. If you haven’t, I’d certainly recommend it. You can pick up a free copy of 1984 today, and also get a 30-day trial of Audible, just use my link, Audible.com/Isaac or text Isaac to 500-500. Let’s take a moment to better define what we mean by Mind Control and what types of techniques need to be considered. There are of course levels to the intrusiveness of mind control. At the lowest level, there’s simple influence, like when parents, educators, journalists, and others simply show and tell you things aimed at getting you to view things a certain way; if those people are your only sources of information, their influence will shape your thinking for a long time, even after you’re away from them. When that influence becomes more direct and is aimed at shaping your political behavior, it morphs into propaganda. Subliminal methods is quite a broad category, and it includes some well-proven techniques used in movies and advertising and by persuasive speakers; what they all have in common is that they exploit the fact that we can only consciously process part of the information we take in, and much of it gets processed only unconsciously. We’re getting into sinister territory with conditioning and aversion therapies, which are called brainwashing when they’re applied forcibly, although stories like A Clockwork Orange explore its benign, socially beneficial uses. Then there’s neuro-hacking, where we directly alter your thinking, using either neurochemicals or nano-bots, by reconfiguring the neurons you think with. At the highest level of mind control, a new species could be engineered, or an existing one re-engineered, to simply possess or lack the cognitive traits of interest or of concern. There’s no need to police or even forbid activities that no one is inclined to do. Obviously the categories in this loose hierarchy overlap quite a bit, and even there being six of them instead eight or twenty is a bit arbitrary. Most of the methods we’ll discuss today arguably match more than one of these descriptions. In a society where mind control is ubiquitous and successful, you wouldn’t really need a draconian police state or constant surveillance. There’s no need to hunt for rebels if no one rebels. And indeed, citizens will surveil one another; if their neighbor expresses an anti-societal thought, they will render assistance to him by contacting the authorities, the same way you or I would call an ambulance if our neighbor fell off a ladder. It’s not betrayal, and they’re not choosing loyalty to the state over their friendship with him, they’re doing him a favor, and he’ll thank them sincerely when he gets home from his brain scrubbing session. After all, who doesn’t want a nice squeaky clean brain? Not a very dystopian civilization on the surface. In fact, the really disturbing thing is that it might appear incredibly Utopian. It’s likely everyone would be brainwashed, even if only for things as simple as conditioning to keep them from injuring anyone except in desperate self-defense and to be courteous and not to steal—behaviors we already do our best to indoctrinate people into. If everyone has that, even the Supreme Dictator, it’s hard to call that an evil empire. Of course the idea is usually that the folks in charge are exempt from the conditioning and use it to enslave everyone else. Even for the other case though, where it is everyone without exception, the notion makes me rather queasy and I doubt I’m in a minority there. We have a term here for such civilizations, which is Post-Discontent Civilization, in contrast to a post-scarcity civilization. This has a fairly hazy borderline, much like brainwashing and indoctrination versus conditioning children to act civilized, but the simple example would be as follows: In a post-scarcity civilization people can get almost anything they want without much trouble and have a lot of luxuries. In a post-discontent society, everybody has been made very content with what they have, which may be virtually nothing. You probably indoctrinate kids in a post-scarcity civilization to avoid excess too, like wanting their very own planet, they might still want one but feel embarrassed to pursue that request or tell people about it, for instance, while in a post-discontent civilization they might work 16 hours shifts everyday while coming home to a filthy rundown hovel, and be entirely blissful about that. This is the concept that truly terrifies us, it goes beyond even the feeling that it’s better to die on your feet than live on your knees, it’s the notion that you could be turned into a drone who is entirely happy with that existence. That you could be totally oppressed and overjoyed about it. This is doubly problematic, because we’re aware of people for whom this is already true, particularly for mild forms of it, and because it comes up often with artificial intelligence too. One of the most common proposals for dealing with intelligent machines is to make them so that they love their work, and that’s one of those thin ice areas. On the one hand, it’s certainly kinder to make an intelligent vacuum that loves cleaning floors than one that hates it, but on the other, if we were raising kids to enjoy being floor cleaners I think most of us would be pretty aghast at that. The analogy might be a bit iffy though, first, there’s no reason to make a sentient vacuum cleaner, and we do not react the same to being told a kid was raised to love being a doctor or astronomer. Second, there’s also that line between compulsory and encouragement, and the motivation for it. A lot of parents have some dreams in mind for their kids, but they’re rarely compulsory and typically done for that kid’s benefit, or perceived benefit anyway. Our objections tend to come when it feels like it went beyond encouragement or wasn’t really about the child’s best interest. A lot of us end up following those parental dreams and loving it, I can’t even write my own name down without being reminded I do, but that doesn’t mean we were compelled to do it or that the motivations for that encouragement were bad. And in a wider context, picking yours kid’s profession has been more the rule than the exception historically. Of course there’s a reason why we disapprove of that nowadays. It is one of the reasons I tend to dislike the notion of creating artificial intelligence with preset motivations we picked with our own best interest in mind, not its own. I think there is a genuine difference between creating an AI to be a happy vacuum cleaner and building a bunch meant to pilot probes off to space, who are encouraged to want to do that but still given a choice. And a real choice too, not “You don’t have to pilot the probe, but if you say no you’ll be scrapped or used to run sewage treatment plant.†Fundamentally you just avoid building something with anymore intelligence than it needs, and thus avoid much of the problem, as being built to a task that requires intelligence and judgement is likely less demoralizing than being built for the purpose of passing butter and for some reason being given sentience for this task. I think you need Informed Consent and enough leeway in the encouragement that alternatives are both available and attractive. Using that probe example, let’s say we raised a bunch of artificial intelligences to run probes to other worlds, one reason to do that might be because you want to be sure that if they get out in deep space, far from supervision, they don’t go off the rails and decide to exterminate some alien planet or park in a solar system and start manufacturing warships to come back and conquer Earth. You have guidelines for what you want them to do and not do while they’re out far from Earth, but you want them smart so they can make good decisions and have some flexibility to pick those and carry them out. In such a case, being absolutely certain they will not break one of those key rules is not only preferable, but arguably the best moral action. Let’s humanize it though, say we were launching a manned ship instead with a crew. Not folks we raised from birth or anything, regular astronauts who entered a program voluntarily and enthusiastically. But we tell them the final step is they have to submit to indoctrination to follow certain guidelines. Very extreme indoctrination, essentially unbreakable. Not weird or secret guidelines either, ones they’ve been told about during the entire program. They don’t have to submit to the indoctrination, but they don’t get on that ship if they don’t. No other coercion, they might get picked for another program, they can leave for a new career, they won’t be blackballed or mocked for refusing, but no indoctrination, no voyage. We’ve decided we simply can’t risk sending out explorers who might, however unlikely, decide that the planet they found out there with life on it should be conquered, sterilized, or even visited and we need to be sure of them because when they’re light years away we have no way of enforcing that policy. Tricky ethical case, because it was all voluntary, they knew what the rules and guidelines for the mission were from Day 1 and agreed to follow them, and a “Don’t you trust me?†defense isn’t exactly reasonable, because it’s not them arriving at that alien planet, it’s them spending a big chunk of their life in stressful traveling conditions and isolation before arriving there. If I send a bunch of colonists off on a 40 year journey to colonize Alpha Centauri, but with the caveat that if they find so much as a microbe on that planet they are to scrap that plan, I’m going to have my doubts about if they’ll stick to that. This is the problem, we know the mind is programmable, at least to some extent, and we know we’ll get better at it, and we know there are some very good reasons to employ it. Ethically, I would much rather tell a kleptomaniac that they could just be brainwashed into not wanting to steal anymore and go home tomorrow rather than stick them in a cage for a year, an expensive cage too, and so long as they’ve been given a choice, and both choices are reasonable, I don’t see the problem. A coercive ultimatum, like telling them it would be life in prison or the brainwashing, is different, so is an unreasonable option, like being brainwashed above and beyond the negative behavior, so that they couldn’t lie or do anything selfish anymore. He stole, and so his option is to take the usual and reasonable punishment, or have that specific bit of him adjusted so he won’t repeat the behavior. It’s difficult to argue his treatment is unethical in such a case. Tied into that, we already do a lot of voluntary behavior modification, and while one can argue about how effective hypnosis is, people who pay for it generally assume it is effective, which is what matters for the ethics of it. Similarly, whether or not a medication designed to break an addictive habit is 100% effective or just helps most folks is not our major concern. There’s not much difference in between taking a pill that makes you inclined to quit smoking and reduces the urges versus one that absolutely and instantly removes the desire entirely, except that the latter will sell a lot better. The ethical issue there is if them taking it was voluntary, and if it was full and informed consent, they knew what it did and all of what it did, including side effects, no secret additional effect of making you ultra-loyal to the regime too. Some folks might want to outlaw that or at least control it, prescription only or only administered by a doctor so someone couldn’t slip it to someone else, but there’d certainly be a big market for such voluntary mind control. Most of us would still regard such scenarios warily, but wouldn’t call that brainwashing. The effect was reasonable and they chose to do it, there was no coercion involved, or at least no unreasonable coercion for the prisoner example. We have to contemplate higher tech scenarios for this though, and it’s good to set our moral groundwork first, that you either agree with the reasoning thus far, and why, or do not, and why not. Giving someone a scientifically formulated aphrodisiac and giving them some love potion brewed up by a medieval witch or alchemist is identical ethically if the person administering them believes both work, it doesn’t matter that the latter is just sucrose and water, any more than you shooting someone with a gun full of blanks is okay if you thought the ammo was genuine when you pulled the trigger. That’s important to keep in mind because, for instance, right now we invest a lot of money into marketing and advertising, and that includes research to make it more effective, which is blatantly an attempt to influence your behavior and mind. This is mostly viewed as okay though as it is just influence, and people know they’re being influenced and to what end and why, and they can resist it, and the folks doing it believe that too. The game might be a bit different if some computer was exactly tailoring a message to you as an individual and with such effectiveness you had no realistic way of not doing what they desired. That’s part of the perceived danger of the various technological approaches visited in science fiction, they are seen as not being resistible, either because they are not or we have no experience identifying that method of influence or countering it. Perfume or cologne is an attempt to influence people, but we know it, can detect it obviously, and the effect is mild and easily resisted if one wishes to. But many would be different, you might not know, you might not be used to it, and you might not be able to resist it even if you wanted to. There’s so many avenues too. Chemicals, visual stimuli, pheromones, hormones, subliminal messages, and so on. Indeed pretty much anything connected to your brain to feed it nutrients or data can be used to influence someone’s thinking, and the higher the bandwidth, the more subtly or thoroughly or quickly one can do it. Vision is very high-bandwidth, millions of bytes of data a second, far too much for your conscious mind to process, and thus particularly vulnerable to sneaking something through, such as subliminal messages. So, imagine something even more high-bandwidth, and to which we have no neurological, biological, or culture defenses against. This would be the brainwashing ray or direct implants into the body. The typical DNA or RNA in a microbe or virus already has an awful lot of data in it too, so a tailored virus or pathogen need not be limited to simply screwing with your biochemistry, it could contain images. We get an example of something similar in Alastair Reynolds’ novels Chasm City and Absolution Gap, with something called an Indoctrinal Virus, that can infect someone and give them visions or predispose them to believe something, not just screw them up chemically. And you hardly would have to limit yourself to just one virus either, you could infect someone with a whole slew of viruses, each containing different chunks of data. We could also send in nanomachines to do such a thing. Needless to say if you’ve got neural implants already, neural laces in your head or machines to augment mind or body, you are even more vulnerable to very high bandwidth attacks such as neural hacking. And your brain is quite susceptible to electromagnetism, so while the brain controlling rays or fields of classic scifi are rather naïve about the implied complexity, it is probably possible. We do want to be careful though, because these new methods aren’t necessarily any more dangerous than existing ones except in being unfamiliar and more sophisticated. We can get familiar with them and our defenses can be sophisticated too. We’ve been dealing with fears of mind-controlling drugs or devices for generations, and with computer viruses for decades, and while those are legitimate concerns, nobody’s brainwashed everyone or hacked everyone’s computers so far. Defense has been slow to improve but has kept up. It’s likely to be a big market in the future though. You buy things to enhance the mind, or improve it, hardware or software, and you buy things to protect the mind, and people will tend to avoid a lot of new technology till it’s been tested and out there working for a while. You might want the newest and best brain-enhancing devices but hesitate because of cost and unknown risk, you don’t want the buggy or vulnerable new stuff, or to be offline waiting for a patch. Beyond that we have the concern of something radically new getting in before we can defend against it. Or something developed and deployed in secret by some shadowy group. But we’re mostly worried about the slippery slope of good intentions. That’s a very legitimate concern, and the scariest part about it is that technology is dangerous and brainwashing is actually one of the best defenses against dangerous tech. As an example, one of our big concerns is someone might develop a way to make nanotech or 3D printers or replicators that can make just about anything from a blueprint, so someone could make a doomsday device or super-virus in their basement, any crazy single lunatic could wreak havoc on us or even destroy us all, just one lone wolf. If a shadowy group or totalitarian government controlling us is a threat, at least it’s usually assumed to be somewhat sane, just villainous. We’ve no shortage of individuals who are crazy and the idea that any one of them might kill us all could drive a society to want to limit such technologies. The alternative to such limits on tech is limits on minds instead. Imagine if we felt the only way to keep us all safe would be to all get mind scanned for dangerous tendencies and controlled to prevent them. These could still be somewhat voluntary and customizable too. You might give everyone an implant that prevented them from engaging in mass murder, but you might let folks pick between a range of options instead and based on their security risk. You can’t learn certain sciences without agreeing to being conditioned against using them for certain purposes or teaching them to others without permission. You can not operate a 3D printer or train to use one without agreeing to be conditioned to not use, make or distribute banned or restricted templates. You might get to select between being conditioned to be non-violent or be able to pick instead to have your mind scanned occasionally for instability or be followed by a drone that watches you. Some folks might prefer conditioning to not do something they really don’t want to do anyway if that exempted them from privacy intrusions. This raises the slippery slope issue, even assuming such a civilization isn’t already off the cliff and over the moral event horizon, but it also raises one of the weirder Fermi Paradox solutions. With the Fermi Paradox, the question of why the Universe seems absent of other intelligent life even though it is ancient and immense, we always have a problem of why civilizations don’t spread out. Common suggestions are that they can’t, because space travel might be impractical, or because civilizations kill themselves off, or because intelligence is just super-rare. Alternatives tend to focus on why civilization might not want to spread out to the galaxy. A point I once raised in discussing this is that it doesn’t matter if most people in a civilization don’t want to colonize the galaxy, because some of them probably will, and if it is practical to do so, then it only takes a handful of people in a civilization, any civilization, to colonize the whole galaxy. Unless you are willing to flat out blow up any colony ship that tries to head out of your system, it really doesn’t matter if most of your people don’t want to colonize the galaxy. But if your civilization feels that limited mind control is the only way to keep everyone safe, colonization could get to be rather dangerous to you. All those folks elsewhere, separated by decades or centuries of light lag, are hard to monitor or reinforce their conditioning if it weakens or to do anything about if they skip off track. Remember, this could be a real danger too, it’s possible just one person could make a doomsday device you can’t defend against, and such a thing could be manufactured at Alpha Centuari and sent back to Earth too. One colonist breaking their conditioning might be able to walk over to the colony’s 3D printer, and a minute later have a device that lets them takeover their whole colony and send back a genocidal armada to Earth and all of its colonies too. Alternatively a solar system is a big place, and we’ve seen how many people you can put in one and how long you can extend the lifetime of a sun or protect yourself from natural threats. You might feel that is more than enough and more than safe enough, and if such technologies exist they mess with our Exclusivity issue with the Fermi Paradox. We often toss out Fermi Paradox solutions not because its improbable a civilization might do something, but because it’s improbable every civilization would, space travel wouldn’t seem exclusively limited to peace-loving aliens who dislike meeting primitive cultures, or don’t like to interfere with them, so solutions reliant on aliens staying away from Earth out of disinterest or principled non-interference don’t work well. Even though many would probably do one or both. However, if technologies exist which are ultra-dangerous and can be easily created by any one person, that’s a threat every civilization would have to deal with and not many solutions come to mind, indeed that would seem like your options are extinction or mind control, though I would imagine, or at least hope, there were some alternatives. If there were not, you might easily have a Universe that was full of nothing but isolated mind controlled worlds as islands in a vaster sea of empty or dead ones. Nobody expands out much for safety, and nobody talks much because there’s not much to gain from doing so, and it does enhance risk. Including the risk that another civilization might think your safety controls weren’t good enough and come by to enhance it with better mind control of their own, or just wipe you out. The potential gain, new technologies and new ideas, new science or art or philosophies, what we tend to view as the big boon of meeting a new civilization, is probably not very attractive to them since those could rock their very fragile boat. I don’t think this scenario is too likely, indeed I tend to suspect that we will constantly be improving all our counter-measures for dangerous new technology right along with that new technology, but it drives home the point that mind controlling technology is potentially very seductive even to civilizations that are pretty benevolent and free of corruption, even ignoring how easy it is to slide into a totalitarian police state--or ironically even worse, a totalitarian state that doesn’t need police anymore. It’s a really scary thought and for that reason one popular in fiction. From films like Clockwork Orange to books like Lowry’s The Giver or Huxley’s Brave New World, or scifi episodes like Star Trek: The Next Generation’s “Chains of Command†or Blake’s 7, we see a lot of authoritarian dystopias that use such methods, and often arising from good intentions. The Big Brother of all of these fictional works, though, the one that inspired so many others and terms we regularly use nowadays like Big Brother, is George Orwell’s 1984 and it really paints a portrait of how you don’t even need sophisticated technology or a contrived plot for how the grim, authoritarian, essentially invincible police state can arise. I also find it rather grimly amusing that the book has often been banned in various times and places as subversive or corrupting. A very influential work, as mentioned, and one adapted to film or TV quite a few times, often quite well too, though as usual, the book is better. If you haven’t read it, I certainly recommend doing so, and you can pick up a free copy of 1984 today, just use my link in this episode’s description, Audible.com/Isaac or text Isaac to 500-500 to get a free book and 30 day free trial, and that book is yours to keep, whether you stay on with Audible or not. So a pretty grim topic today, but an important one. Next week we’ll be looking at something rather more upbeat, as we start off the Earth 2.0 series by looking at Seasteading and making artificial islands, and we’ll move on a couple weeks later to explore deeper seas with Colonizing the Oceans. Before that though, we’ll return to the Generation Ships series to contemplate how you would keep a culture strong and stable on such a ship over the many millennia it might need to exist to achieve its mission, and just how long such a ship could be deployed, in “Ark of a Million Years†As a last note, we’ve talked occasionally of doing an end of the month livestream for Q&A, and we’ll be doing our first one this upcoming Sunday, September 30th, at 2pm Eastern, 1800 UTC. We’ll continue doing a monthly livestream after that, though we’ll figure out the time, dates and show format as we go. For this first time, though, it will be this Sunday Afternoon, and I hope to see you then! For alerts when those and other episodes come out, make sure to subscribe to the channel and hit the Notifications bell. And if you enjoyed this episode, please hit the like button and share it with others. Until next time, thanks for watching, and have a Great Week! This video is sponsored by CuriosityStream. Get access to my streaming video service, Nebula, when you sign up for CuriosityStream using the link in the description. We often worry about Earth getting overcrowded, but in truth it’s not about how much space we’ve got but how much energy & resources we need for those people, and if we’ve got those, we might be able to support far more people than today and in far more comfort than now. We have a concept we discuss sometimes on the channel called an Ecumenopolis, a planet-wide city, and these show up in fiction fairly often and usually as capitals of vast interstellar empires, like Coruscant from Star Wars or Trantor from Asimov’s Foundation series or Earth itself in the Warhammer 40k setting. They are also often depicted as having a trillion people on them or more. I thought today though that we’d try to ask ourselves what it would take to have a trillion people on Earth and what the Earth would look like if it did. The first and most critical point to hit though is that a trillion people, while more than a hundred times as many folks as are alive now, and indeed ten times as many people as have ever lived by most estimates, would not even begin to require a city that covered the whole planet. Earth has a surface area of approximately half a billion square kilometers or 200 million square miles, about a quarter of which is land. If we assumed we paved over everything, from the deepest ocean to the frozen tundra, a trillion people would have a population density of just 2000 people a square kilometer or 5000 per square mile. That’s hardly a small figure, but that’s not even a fifth the population density of New York City, which is not even the most densely populated city in the world. And while those not living there mostly know it for its skyscrapers, indeed few cities have more, they’re only a tiny fraction of the buildings there and not where most folks live. Even if we didn’t have any multi-story residences, even if we limited ourselves only to land and not sea, you’d still have 1400 square feet or 130 square meters per person, hardly a cramped home for a single individual, or even a modest family, and again, that’s no second floor and no basements, let alone towering skyscrapers or vast artificial islands or sea-steads. Now, needless to say, that doesn’t include any businesses or public buildings or roads, nor gardens and parks, let alone farmland or nature preserves. People need food, and raw materials, and an ecology of some sort, and energy for it all, and also some way to get rid of all the waste, which includes the main limiting factor, the heat leftover from producing and using all that energy we’d need. We often worry about even supporting our current population of 7.7 Billion, and that was a concern before I was even born in 1980, when the earth's population was just 4.4 billion, little more than half of our current population. Indeed it was quite a concern even back in 1798, when the population was approximately 1 billion, a thousandth of what we’ll contemplate supporting today, when Reverend Thomas Robert Malthus wrote his famous, or perhaps infamous, “An Essay on the Principle of Populationâ€, which gave us the concept of Malthusianism and Malthusian Catastrophes. I should note that while I and many others are often terribly critical of Malthusianism, indeed I tend to use it as a curse word, it’s no criticism of Malthus himself, who simply observed that growing populations need more food while farmland is a static value. Or essentially that finite resources can’t support eternal growth, thus eventually requiring you either limit your population or suffer catastrophe and hardship as people begin starving and the likely chaos that ensues. And the point is an entirely valid one. Those of us who object to it generally are doing so in a short term sense of improving technology letting us get more food and production from less land or material or energy. Whether or not our population growth will continue to the point that we even need to house a trillion people on Earth or if there is some maximum limit to how many people we can support, our objective today is to show that we could house this many on Earth and present what sorts of technologies might be needed. Fundamentally you need a lot of energy, because with enough energy you can deal with all the other problems like food, every problem except getting rid of heat, and we’ll return to that point in a bit. You obviously can’t run a civilization much larger than our current one off fossil fuels, but we do have the option of nuclear fission or orbital solar power. The thing is, you need a LOT more energy to support a trillion people than simply what you use nowadays times a hundred or so. Hidden in the background of all our energy budgets is the massive free supply we get from the Sun, our hidden solar economy that long predates the invention of solar power. At any given moment the Sun is shining down on Earth approximately 200 thousand, trillion watts of energy, which either gets reflected or gets absorbed and later re-emitted as infrared waste heat. Only a small portion of that absorption is into photosynthetic plants and organisms, essentially the foundation of our ecosystem and food chains. Approximately 98 to 99% of the photons reaching us never get involved in photosynthesis, being absorbed by other things, reflected away, or just not being frequencies plants use for photosynthesis. We also don’t use the majority of the energy converted this way for human food either, and even more of it gets lost to biological middlemen between the sun hitting a plant and something hitting your dinner table. Humans only need about 100 watts a piece of food energy to live, which would be 100 trillion watts for a trillion people, whereas even if we assume that only 1% of light was used in photosynthesis, that would leave 2000 trillion watts. Humans would only have to achieve 5% efficiency on using that foundational biomass that itself is only at 1% efficiency to feed a trillion people. So yes, we probably could switch over to hyper efficient plant varieties grown inside greenhouses with high internal reflectivity to feed those trillion people, while probably still keeping a large portion of the Earth’s surface area as ecological preserves, especially if we were supplementing those preserves with food we’d grown to help ensure biodiversity and long food chain species remained plentiful. Needless to say, switching over our own diets to vat-grown genetically modified super-algae or switching over our bodies to be cybernetic, or our minds uploaded digitally to run on computers, would also potentially allow a trillion or more people too. However, we’ll mostly bypass those options for today, especially as the cybernetic or mind-uploading technologies do not yet exist and also could only exist in tandem with other technologies that also permit far more people. As an example, if you can upload a human mind to a computer, it means you already have the capacity to make robots more than smart enough to be doing a lot of work with little guidance up in space, which unlocks options like power satellites and space farms, and obviously orbital habitats and planetary colonization too. Similarly, if everybody’s gone cyborg to the degree that they need little or no food, then they can cheerfully live off Earth too without even needing any of the habitats like the O’Neill Cylinder that we often discuss as future homes for humanity. Our goal today is not specifically to see how we can house a trillion people on Earth with the minimum technology, but we will be trying to keep to the lower-tech and nearer term solutions. If you’ve seen our Matrioshka Worlds episode then you already know that yes, you can rather easily cram many trillions of people on Earth with a few core technologies, and they wouldn’t feel very cramped at all. So we are trying to limit ourselves mostly to near-term tech. However, it is worth keeping in mind that even if we were growing at 20th century levels, quadrupling every century, or doubling every 50 years, we’d still need 7 doublings or about 350 years to get to a trillion people, and honestly such growth rates would probably only occur in a civilization that had biological immortality or close to it, or one that had banned birth control or really put a cultural focus on having as many kids as you can, which is certainly possible but would generally be the opposite direction of where we’ve been headed in recent generations. It is worth remembering though that much if not most of our declining growth rates are from a drop in accidental or unintended births and folks starting families later and/or keeping them smaller. If you suddenly can extend human lifespans and fertility spans, and if there wasn’t a perceived need to watch our population numbers, that trend could flip right back the other way and then some. A civilization where folks can live centuries while being biologically 20 or 30 something and with no pressing worries about food supply or ecological ruin is one that can grow a lot faster than doubling every 50 years and probably would. People like kids, and a pretty big chunk of the population would cheerfully have another one every few years indefinitely if they were economically and medically able to do so and had no worries about a Malthusian Catastrophe. So while I personally doubt we’ll hit a trillion people within a mere 350 years, by 2370 AD, either all on Earth or with some or most in space, it is possible and could happen even sooner than that. Key notion though, if we’re discussing near-term technologies, is that 350 years is a long time to discover these, and in general we’d only need 1 or 2 of them out of several that would do the trick for allowing that many people, and most are technologies I’d honestly be surprised if we didn’t have by the end of this century. This would seem especially true if we have many times our current population to throw at scientific research and technological advancement. For a civilization on the rise, the number of scientists and specialists in general that you have rises faster than your population does. With the caveat that if we grew too fast, we might downward spiral into a Malthusian Catastrophe, though probably to no one’s surprise I doubt the former will happen and very strongly disagree with the notion that we’re already in one. But that’s not the topic of this episode so we’ll list that as an opinion and bypass it for now. Short form, if you’ve got more people and they’re not all busy trying achieve basic survival or cannibalize each other, you’ve got way more scientists working on cracking these technologies. So what are these technologies? Well, there are plenty but the three big general types would be improved automation, enhanced biological knowledge and manipulation, and superior and renewable energy. Each of these has multiple avenues of development and each could achieve our goal, a trillion people on Earth and in a sustainable way, either by themselves or in tandem with the others. On the improved automation front first, if your robots are really good it utterly alters your economy even if that’s your only new technology. Almost everything gets cheaper, which includes building stuff like solar panels, batteries, greenhouses for food, the robots that plant, tend, and harvest that food, and very large structures for folks to live in. There are all sorts of pathways available to us that aren’t economical right now, but way more productive and efficient, if your simple labor tasks are being done by robots. We have a lot of crops we don’t grow much because they are labor intensive, even though they produce more calories per acre than most of our staple cereals crops. We also grow stuff under an open sky because glass or polycarbonate greenhouses are quite expensive to build and maintain, but such structures produce an order of magnitude more food per unit of land area and use far less fresh water and nutrients and those climate controlled facilities are also less susceptible to disease and disrupting the local ecology, or being disrupted by it, such as via a swarm of locusts. If your robots are making the glass, doing most of construction and maintenance, and tending and picking all the food inside, not only do you have a huge boost in food production but you’ve got way more folks available to be working on new technologies too. Such robots hardly have to be brilliant either, barely insect level. Improvements in biological sciences, our second avenue, could potentially achieve the same thing, hacking plants to be more efficient, perhaps also hacking animals to farm the plants. It’s sounds rather less science than science fiction to imagine critters tending our crops or modified organisms growing greenhouses like they grow shells or coral, but maybe not that big a jump either. Nor would be hacking plants to be able to maximize their use of sunlight, potentially growing various simple organisms that we could process and print into whatever food we felt like, or at least a facsimile good enough to pass the taste and texture test. Not that it necessarily has to, while food is a great source of pleasure and we’re all glad for the diversity that modern agriculture and transport permit us, most of human history didn’t allow for particularly diverse diets and much of our culinary arts were about how to make tasty or at least edible food that was mostly made of whatever the local main staple crop was. So I’m quite sure we could find a way to make even some gene-hacked algae types more palatable than what most of our ancestors not only lived on but were grateful for. I hate to call us spoiled, and certainly hope our own descendants will regard us as having suffered great hardship compared to them, but our ancestors certainly had it rougher and the episode is not titled “Can we have a trillion people living in Utopia?†Now the third big one is just energy. If you’ve got a cheap renewable power supply you can just flat out grow all your food under artificial lighting, but that power supply can’t just be cheap and renewable, it needs to be abundant too. Fusion is obviously one option, though shouldn’t be regarded as some magic wand of ultra-cheap energy, and indeed as we mentioned in power satellites, it’s actually not your best way of maximizing how much electricity you can have on Earth. A fusion plant, by default, like any other power plant, is going to be producing a big chunk of its energy as waste heat, and we can only get rid of so much heat without building some of the more over-the-top megastructures like we looked at in Matrioshka Worlds. Alternatively, microwave power transmission from space-based solar removes that problem, ground based microwave antennas, rectennas, convert microwaves into electricity at 80-85% efficiency, way better than you’ll get out of any power generation system that relies on boiling water to turn a turbine. It can also be beamed pretty much to where it’s being used, cutting down on transmission loss to heat, which gets a big chunk of our current electricity, and it’s all off-Earth, so heat created in converting sunlight to microwaves can be mostly disregarded. You can also be throwing solar shades or mirrors up around the planet or at our L-1 Lagrange point that are transparent to visible light but not infrared, which really has no value to our planet besides keeping it warm. Needless to say if you’ve got robots you can do this mass construction project rather easily and based off the Moon, it requires no new tech, besides those robots, and not really very much considering the majority of the work is basically smelting and rolling mirrors, not exactly a process that’s hard to automate. Now suddenly you can be dumping in several thousand trillion watts of electricity into your power grid without overheating the planet and of course it’s fundamentally solar so it’s quite renewable. This one works great in tandem with improved automation because it lets you do multi-story climate-controlled artificially lit food production mostly built and run by those robots. This also really only requires software improvements, not any vast leaps in physics or chemistry. If you’ve got a climate-controlled multi-level warehouse with reflective walls and ceilings and LED lighting calibrated to just the right quantity and spectrum for maximizing photosynthesis of a given crop, with most of the grunt work of maintenance and construction being automated, you’ve got a massive farm with a very minimal footprint. Indeed you can potentially have skyscrapers hundreds of stories high that on the inside all look like suburban housing and hydroponic lands and farm field, or even forests. That’s more or less the notion we looked at in Arcologies some years back, and as we noted in its companion video, Ecumenopolises, going this route let’s you get away with cramming your entire population into giant buildings while leaving 99% of our planet’s surface entirely wild if you wanted too, and with a trillion people, rather than the usual bleak look of Ecumenpolises, planet-wide cities, in science fiction, where the whole planet is nothing but metal and concrete. Now that’s not to say you would do it that way, and each of these potential technologies would likely result in a very different setup, and even more if in combination with just one other. As an example, if you’ve gotten ultra-strong, cheap, and durable construction materials, you can do a lot of this multi-level growth and housing without even needing better automation, because building them is a big investment of time and money but they don’t really require much maintenance once built, unlike modern structures. Similarly, if you’re content to do space-based farming and have built orbital rings for mass conveyance of material on and off Earth, you don’t need to grow any food on Earth and can just ship it down. Again our big issue in terms of land is food production not housing or any of our other buildings and if we’re just talking housing and other such facilities, you could cram a trillion people into large skyscrapers with lavishly spacious apartments and not even use a percent of our land surface, or even into subterranean facilities and not even see human civilization on the surface except where the tethers from the orbital rings carrying cargo and power entered into them. Of course it’s not just technology that would control the setup, but taste and preferences and specific economics, all of which are pretty unpredictable and probably rather fluid and variable from culture to culture, so you’d probably see a mix of options in use even if one was working better. Note that not all of these options involve utilizing space, rather than sticking just to Earth, but most do and it does raise the question of why you would have a trillion people on Earth, especially since most of these setups also imply you could be doing a lot of the other options we’ve looked at, such as O’Neill Cylinders or terraforming other worlds, where folks might prefer to make their homes. Ultimately though, for our original question, “Can you have a trillion people on Earth?â€, the answer would seem to not only be yes, but yes and probably much more comfortably than we live now and without having to pave over everything to live in some barren world of concrete, metal, and smog. And while to do this probably does require a fair amount of technological advancement, even if we see a spike in population growth, we should still have a few centuries to make those advancements and work out the details. So yes, we probably can have a trillion people on Earth one day, but it's probably not something we need to be rushing to do any time soon. One thing we didn’t discuss too much today is how you’d handle all the waste that some Ecumenopolis of trillions of people might generate, everything from regular garbage to waste heat, and we discuss that in our episode “The Future of Garbageâ€, which is out now for early-release on Nebula, along with Conscious Stellar Objects, which contemplates both how life might originate, naturally or artificially in or around stars, and our Nebula Exclusive Series, Coexistence with Aliens. Nebula, our new subscription streaming service, was made as a way for education-focused independent creators to try out new content that might not work too well on Youtube, where algorithms might not be too kind to some topics or demonetize certain ones entirely, or just doesn’t fit our usual content. And if you’d like to get free access to it, it does come as a free bonus with a subscription to Curiositystream, which also has thousands of amazing documentaries you can watch, on top of the Nebula-exclusive content from myself and many other creators like CGP Grey, Minute Physics, and Wendover. A year of Curiosity Stream is just $19.99, and it gets you access to thousands of documentaries, as well as complimentary access to Nebula for as long as you're a subscriber, and use the link in this episode’s description, curiositystream.com/isaacarthur. This Thursday we’ll return to the Fermi Paradox series to contemplate the scenario where civilizations exist and are talking, but we just can't hear them, in “The Fermi Paradox: Whispers in the Nightâ€. The week after that we’ll be teaming up with our friends over at What If to consider what if life emerged on Low Gravity Planets, and then we’ll close the month out with our Monthly Livestream Q&A on Sunday, March 29th. If you want alerts when those and other episodes come out, make sure to subscribe to the channel, and if you’d like to help support future episodes, you can donate to us on Patreon, which is linked in the episode description below, along with all of our various social media forums where you can get updates and chat with others about the concepts in the episodes and many other futuristic ideas. Until next time, thanks for watching, and we’ll see you Thursday! This episode is sponsored by Audible. With each New Year we celebrate the forward march of time, and for some civilizations that march may already been a very long one. So today’s episode makes the start of our seventh season here on Science & Futurism with Isaac Arthur, and I am your aforementioned host, Isaac Arthur. Way back in our second season, when we first started doing weekly episodes, we had an episode called Civilizations at the End of Time: Black Hole Farming, which was long our most popular episode until being passed by its sequel, Iron Stars. The End of Time series is one of our most popular series on the show and looks at how civilization can survive the death of worlds and stars, the encroach of entropy, and last till time ends or at least has no meaning. This is an important concept, of which our current understanding in cosmology leaves a lot to be desired. There is no End of Time per se, just a point where things have run down so much you couldn’t even find the energy, or raw materials, to build a clock or calendar, let alone support anyone who would have a use for such a thing, and that series looked at ways to push that back and keep civilization going far longer than we’d expect. The beginning of time is quite a different story, as we currently assume it has a definitive Time “t equals zero†at the Big Bang. That’s debatable too, and there’s a lot of theories about what the state of the Universe was before that, if such a concept as ‘before’ can even mean anything, or if there might have been a Universe before that event, but it's generally accepted that nothing was alive and kicking here when it happened, since that event was so energy intense, hot, and dense that it made the fiery cores of stars or supernovae look calm, cool, and sedate. On that same note though, late-Universe civilizations would regard our current era as so short and hot and dense that the period of star formation would simply seem like part of the big bang too, so we will play with that notion a bit today and ask if life could have developed or existed even in those minutes right after the Big Bang, or might have in Big Bangs in other Universes. Though we will principally ask today what is the earliest period in which biological life might have formed. We will also ask about some big questions, such as might folks have survived an earlier Universe and migrated here, or even made this Universe as their new home or at least their legacy, and might we survive our Universe’s eventual death by doing the same. One key point we focused on in Civilizations at the End of Time that applies equally well to the beginning of time, is that the basic mechanisms of biology and cognition will operate on timescales depending on the rate at which the switches fire and flip. For example, our neurons fire about 200 times a second, so the basic scale of human thought and our ability to perceive events is in the millisecond range. If you live in a nearly dead Universe of hyper-cold and hyper-efficient computing, you can support a whole civilization on a light bulb instead of a star by just running it very slowly. The analog of neurons firing might occur on the order of millions of years, so a thinking process might last for trillions of trillions of trillions of years. The converse is very likely true, that early in the Universe, when the energy density was high and ambient entropy was much lower, life of the era might have been based on sub-atomic scale interactions taking place in trillionths of a second or even less, resulting in an epoch of the Universe lasting literally only an eyeblink to us but permitting some mind built upon that scale to have experienced what we could only experience in eons. If such life or civilizations ever existed, they could only have lasted in that form for as long as the universe was hot enough, dense enough, and low enough in entropy for them. If they did endure and adapt to the rapidly cooling universe, the adaptation would be so extreme they’d be unrecognizable from their original forms—much like for example an originally human civilization adapting to conditions at the end of time, as post-biological life. We’ll return later to contemplating the very earliest things that might have qualified as life, but for now let’s contemplate how early in the universe biological life as we know it might have begun. We can rule out the first 300,000 years of the Universe easily enough, which is handy because that’s a period we cannot see, the time prior to what we call “The Last Scatteringâ€, and indeed the reason we cannot see it is the same reason we could not have had biology then. Back then the Universe hadn’t expanded very much – though by this we mean our Observable Universe, a point that will matter later too. Since the Universe was quite small it was also ultra-hot and ultra-dense, so there was no complex chemistry going on. Prior to the Last Scattering you could not even have a water molecule, or any carbon-based molecules, because the Universe was hotter than the surface of a Sun still, indeed it was too hot for atoms to even form. Once it spread out enough that atoms could form, and photons being radiated by all that heat became more likely than not to fly through empty space rather than scatter off that early matter. Before The Last Scattering, the universe was filled with hot matter emitting photons, but as is the case inside a star, those photons were almost immediately absorbed and re-emitted over and over by surrounding matter. At The Last Scattering things cooled and thinned enough that most photons being emitted wandered around without hitting anything and continued to do so. We can see those early photons to this day, as they are still arriving hither and thither throughout the Universe and will always do so, just ever more weak and red-shifted, nowadays they are red-shifted down to microwaves and form a constant background radiation in the cosmos, what we call Cosmic Microwave Background radiation or CMB, a Universe wide phenomena. From a time and space sense it is a wall we cannot see beyond, or before, but there were no civilizations there to see because there were no atoms and molecules to build them out of. So no carbon-based or water-based life, nor options like Silicon Semiconductor Life or any of the other alternative forms of Chemistry we contemplated in our episode Non-Carbon Based Life. It was just too hot and dense for such things to exist. There also weren’t the right types of atoms. Our Universe is mostly dark matter and has been since its inception, but dark matter is not a good candidate for life, especially fast forming and acting life, so we’ll skip it today. Most of the early mundane matter wasn’t a good candidate either, the Big Bang and its immediate follow up would see the formation of just hydrogen, helium, and lithium, and very little of the last, indeed we seem to have even less of it than our models predict, what is called the Cosmological Lithium Problem or Lithium Discrepancy. Given that our models are off on that, it is possible some of the heavier elements also formed in very tiny quantities too, and potentially in ways and fashions that might have seen them getting concentrated in some spots. It is the nature of heavier element formation that it tends to happen in clumps and clumps of high density and energy. Highly unlikely but maybe not impossible, and by about 10-20 millions years after the Big Bang the whole Universe had cooled to the point of being room temperature and you’ll sometimes hear me or others call this the Bathwater Epoch, as it's vaguely conceivable you might have had enough oxygen around in some places to form large pockets of warm water in which very tiny amounts of heavier atoms might concentrate and permit some chemistry and thus life. Though I’d emphasize that this is one of those things that’s possible only in the sense that we can’t flat out say it is impossible that this might have happened somewhere in the vast Universe. It's also one of those possible primordial events in other Universes. The conditions of our Universe were likely very dependent on the tiniest variations in certain physical constants and one in which if the formation of heavier elements in the Big Bang, Big Bang Nucleosynthesis, were even a little more preferred could have resulted in such a Universe having trillions of muddy warm water worlds form in an Early and Warm Universe, and if expansion was a bit slower there, they might persist for eons and permit evolution. For us, even if life did miraculously form then, it would probably have frozen soon after and at best potentially been revived or survived by proximity to one of the first stars forming millions of years after the Bathwater Epoch, then perhaps been blown about the galaxy by the detonation of that star, and world, in those first Supernovae that gave us real quantities of heavier elements. There was a long time period between the Bathwater Epoch and Star Formation, but large clumps of matter like planets take parallel times to cool down so you might have had a remnant of life in some giant ice ball near its still warm core, and keeping life around to the start of Star Formation. That is generally thought nowadays to be at about 250 million years after the Big Bang, and we revised that figure down from more like half a billion to a billion in recent years. 250 Million years is still a long time, but is only about 2% of the age of the current Universe. If we’re thinking of all the Age of the Current Universe as a single day starting at midnight, and now as that second midnight, then Last Scattering event was about 2 seconds into the day, the Bathwater Epoch between minutes 1 and 2, the first star formation about half an hour into the day, the formation of Earth and Primordial Earth Life around supper time, the invention of fire a handful of seconds ago, and the dawn of recorded history less than an eyeblink ago. So needless to say if any civilization arose around those early stars, or the second generation after supernovae, let alone the Bathwater Epoch, they’d have had one heck of a head start on us. Based on what we know though, when could our style of Biology have developed? Well that’s a tricky question because it's all about probabilities and we don’t know what the odds are. We can assume there’s a decent chance in all the Grand Universe of billions of billions of stars that a few freak rocky planets formed early on. Potentially inside that first billion years of the Universe. We often say that it took a lot of supernovae to get us all the rocky material we have now, but that’s not entirely true. Supernova send out dense waves of heavy matter, many generations of them do seed an area with lots of heavier elements to make high-metallicity stars common and rocky planets plausible, but generally the heavier elements in your local neighborhood will come from one specific supernova, not a whole ton of them slowly raising the galactic average. Which they do, but it is entirely plausible a single supernova could result in a rocky planet, though with a narrower range of elemental distribution, as not all heavy elements are produced by exploding stars nor does each exploding star produce the same ratios of elements. Plus star formation tends to occur in clumps, meaning supernovae do too, so wouldn’t take that many stretches of probability to create a solar system like our own inside that first billion years of the Universe, maybe even the first half a billion. We don’t know for certain that life needs a rocky earth-like planet to form on, but that is where we know life has formed and where we expect to find it. We have plenty of examples of high-metallicity stars, where we’d expect to find high-metal planets like our own, that are more than twice as old as our sun. They’re not common, but not ultra-rare either. And that’s the thing about that first case of life, as we examined in our episode Fermi Paradox: Firstborn. The early universe was not very fertile for forming life-bearing planets but it becomes more fertile as it ages. So the first life bearing planet, whichever planet that was, was almost certainly very atypical of planets that existed in its time. It was a first of its kind, formed when the universe was only just beginning to produce planets of that kind and produced them only rarely. When pondering the Fermi Paradox--the big question of why we haven’t found any alien life yet when the universe appears so old, immense, and fertile--we have to not only consider that the firstborn life in the Universe was probably a statistical fluke for its time, but that we might be that lonely fluke. We do not know that the development of life as we know it is even vaguely probable. We have some theories saying so, however most of those begin from the assumption that it is probably natural and work from that, which is a good approach but also logically dubious. One critical notion in considering the emergence of biological civilization is that they follow Darwinian Evolution, from primordial goo to building spaceships, and that they not only do that but do that on something like our timescale. But the timescale of Earth-life has a lot more to do with the speed of cellular reproductive processes than basic organic chemistry, from which it is an emergent property, and we can’t even take for granted that other life runs on organic chemistry. If proto-life in some other incarnation elsewhere in the Universe ran on a slightly different approach that resulted in generations taking ten times as long or a tenth as long, those are likely to be magnified in speeding or slowing the progress of life, but even if they weren’t, it might mean most worlds see their star burn out before life even gets multicellular, or the reverse, that it can spring up so fast to complexity that they’re building spaceships only a few million years after their oceans cooled enough to allow a primordial soup to form. If some life formed as a naturally occurring semiconductor or superconductor vein on some planet, how fast does it experience time? Hypothetically you could have rafts of mostly silicon floating on planets still boiling as magma from their formation mere millions of years after the first giant star exploded to scatter that silicon, and such stars themselves don’t live long either. If the first stars formed 250 million years into the Universe, the first and biggest of them would have detonated and scattered plenty of silicon and other heavy elements only a few million years later. But this notion of life not even working in a conventional biological sense, but being more like a naturally occurring computer, reminds us that you do not necessarily need silicon for computers either, heck our first ones worked on vacuum tubes anyway. If you can arrange for matter to make a switch, a simple on and off under some stimuli, then you create the most basic element for potential life. You can do that mechanically, biologically, with a transistor or a vacuum tube, heck you can even do it with black holes. It doesn’t necessarily have to run on what we think of as normal chemistry, or even normal matter. And if it doesn’t, that gives us some other options independent of the universe aging enough to cool down for chemistry to be possible and for dying stars to give us some new atoms and chemicals to add to the mix. As an example, I mentioned earlier that when we talk about the Universe and Big Bang, as some point-like event from which everything emerged, we just mean our Observable Universe. I’m not even talking about other universes or realities here, we only know the parts we can see emerged from something much smaller – we speculate it was point like though there’s some debate on that, as well as what we mean by that. That does not necessarily mean the Big Bang or our universe started from a single point though. It’s entirely possible the primordial Universe was infinite in size already, and has simply continued to expand, and the chunk of it we can see now just used to be smaller and since expanded as did the rest of it. It’s also worth remembering the Observable Universe isn’t a set size either, and I don’t mean in the sense that the stuff in it is expanding. If you’re taking mass measurements or galaxy counts as the Universe ages you’ll see both dropping, because while we can see further and further every instant as light reaches us from further places in the Universe, our ‘edge’ to the observable Universe is the place at which space in between us and it is expanding faster than the light from it can cover the distance. The Observable Universe a billion years ago was a smaller one, but also a more massive one, a good deal more crowded, and vastly so in the Early Universe. Now the Universe is not homogenous and evenly distributed. Even beyond local space like planets and stars you have got galaxies and superclusters and so on, and it's been like that since its inception, the source of some puzzlement and reason for theories like Cosmic Inflation in the first instants after the Big Bang, but at big enough scales features break down and everything looks like noise and static, what we call the End of Greatness. The resolution, or pixel size of the Universe in this sense, is around 300 million light years. If we divide the Universe into 300 million light year pockets or 3D pixels or voxels, the Observable Universe would be composed of a few million of these pockets. They’re not identical, anymore than snowflakes are, but there’s nothing of significance and structure to distinguish them. They were smaller in the past, much smaller, again we believe non-homogenous distribution of the Universe occurred from the tiniest instant of time after the Big Bang, but assuming the Universe doesn’t magically end right at the boundary of what we can currently see, there would have been a lot more of these pixels in the early Universe. Let’s assume in those earliest moments that each such region represented something like a switch, or neuron, of which there were many billions, or trillions, or even an infinite number, and many close enough to interact. Something like a Universe-brain, that’s a very wasteful approach to computing, where you’re using something in galactic mass scales just to flip a bit, but it’s not entirely impossible that those little fluctuations in spacetime in that early cosmic inflation resulted in something like a Boltzmann Brain thinking at incredible speeds and able to exist at those earlier insane temperatures and timescales because it’s not running on matter. It presumably would have been torn apart in short order, but again it's not raw time in terms of seconds or years that matter but raw processing or events, switch flipping, that controls time in terms of thought and personal existence. Incidentally, as immense as the scale involved is, this is not indicative of a god-like intelligence, again the implication is it needs whole galaxies to be a single switch in the computer, in an infinite or big enough Universe that might be God-like but in terms of IQ per unit of mass, as it were, it would be ridiculously stupid. Alternatively, perhaps it was super smart - smart enough to run simulations of the fate of the universe in the distant future - our present. This would seem to be the earliest possible version of the simulation hypothesis. See The Simulation Hypothesis episode for more on that subject. In this Universe anyway, play around with the initial physical constants and you could get a Boltzmann Brain of breathtaking scope emerging out of a Big Bang, see our Boltzmann Brain episode for discussion of these freak-coincidence sorts of minds. But since we’re talking about other Universes, let’s talk about folks migrating into this one as a source for early life. Now how they would do that, and from whence they came, we’ll consider academic for now, as we have no idea, but let's say they were reasonably like us coming from a Universe with similar basic laws only older and they found a way to make the trip. How old does a Universe need to be to migrate to it successfully? You might assume you could start moving in as soon as the first stars formed but this is probably wrong in both directions. If you’re looking for planets and raw materials heavier than hydrogen and helium, you’d best wait a while, but you probably don’t need stars or heavier elements at this point. Odds are if it’s possible to make fusion work profitability as a power source in something significantly smaller than a star we’ll figure it out in the next century or two, and if you can do that then a Universe of raw hydrogen is one in which you can gather fuel to run your reactors, and fusion is called that because it fuses lighter elements into heavier ones the same as stars do, so you could get your heavier elements that way as a waste product or by running tons of supercolliders. So odds are even we, in a century or two, could make a go at colonizing a Universe still too young to have stars in it, let alone some species thinking about making or traveling to other Universes, as most of our theoretical models that conceive of such things do that through playing with blackholes, wormholes, or similar concepts that tend to all make for methods of power and matter creation better than regular old fusion. Indeed that is one of the better Fermi Paradox Solutions, that civilizations don’t colonize galaxies because they figure out how to travel to other Universes even before their earliest sub-light colony ships could get to another star system and set up shop. It is decently plausible we’ll have figured out all the laws of physics before we’ve reached other stars and if those laws open the door to bigger and better options than slow galactic colonization we probably would do that instead and could surmise other older alien civilizations did so too, and such being the case we never hear from them. Indeed such being the case we might be in some remote pocket of a Universe they triggered into existence and began colonizing. We may be an infestation, or at best squatters, in their universe. It’s a lot easier to colonize a young Universe, everything is closer together so you can reach it faster and can reach more of it too, getting ships to places we could never go now because of Cosmic Expansion. The Amount of Universe you can colonize depends on how soon you can send your ships out and how fast they can go, because the Universe is running away from you and the further bits are running the fastest, presumably faster than light beyond the Cosmological Event Horizon. If they have fusion, or better, they don’t need to wait for stars to form. Now the Universe was still a warm place back when those earliest stars formed, though again that period was already more than a ten times longer after the Big Bang than the end of the Bathwater Epoch, when the whole Universe’s average temperature was what we’d consider comfortable. So that might be the period you’d choose to enter, during the Bathwater Epoch or after but before the earliest stars. The game of life, and being first, is very different when we assume the first entrant already has technology from the outset rather than needing to evolve. That’s why Boltzmann Brains – absurdly improbable random collections of matter that come together to become a thinking entity rather than the slow crawl up Darwin’s Ladder to it, always have the edge on being the first thinking creature, ignoring that we tend to estimate that they are considerably less likely than not to pop into existence even once in an entire Universe our age. Other Universes with other probabilities might have better odds for them, and if our Universe really is infinite then the first thinking life form was definitely a Boltzmann Brain. In our current scenario though life immigrated, so could have evolved elsewhere, but pops into our Universe with all its technology available. How early they could safely arrive and get started colonizing depends a lot on their technology. It is hard to run matter-based technology in a hot place, we discussed how to do that in our Episode Colonizing the Sun but there at least we had the option of using the rest of space as a cold reservoir. 300,000 years into the Universe everything was as dense as the Sun and hot as the Sun’s surface but there was no cold reservoir. So unless your technology encompasses options for bending or breaking the laws of Thermodynamics you probably need to wait till after this period to send in your ships, even if your civilization isn’t biological anymore. But you probably could be in there as early as a million years if it was post-biological, and in the Bathwater Epoch, or a bit before or after, if it was biological. Especially given that you need to make all your heavy elements which is a very energy and heat intensive process and so it's kind of like trying to work in a smelting facility someone decided to place in the middle of a hot jungle, you’re producing huge amounts of heat in a place that’s already uncomfortably warm. So that’s probably the soonest you’d move in, several million if not tens of millions of years after some Universes Big Bang. Now mind you, with different physical constants a Universe might expand and cool faster, but in such a Universe you have a harder time colonizing and are more limited in what you can colonize as the Universe would expand out faster and remove more of it from play. Assuming a civilization is creating it and can pick their constants, or its equivalent in being able to flip their portal to new Universes until they find one with the constants they want, more or less, then there’s actually a fairly narrow range of good picks. You do want one expanding as non-expanding Universes are a death sentence, even if we assumed one that would expand only to about our current density then start contracting or stabilize, though a fairly long death sentence in that case, but anything resulting in stuff being much closer together and staying that way would tend to result in you eventually baking in the waste heat of all your stars, a conundrum we get from Olber’s Paradox which we may discuss some other time. If you have it expanding much slower than ours, or to much higher density than ours, you’ve got big heat issues to deal with down the road and also have to wait longer to colonize it. If you pick for much faster expansion, you can colonize sooner but get less material available, and if it's more than a tiny bit quicker you probably never even get galaxy formation. Which isn’t a problem if you don’t use stars for power or planets for living on, but you still need to collect your hydrogen gas for fusing and without expansion slow enough to allow matter to clump into galaxies and the like, you are doing your collecting in a place with a gas density similar to intergalactic space. It might be initially denser but if it's expanding faster, eventually it will end up way less dense than even our intergalactic space is. You might not care about that either, if you can pop into some Universe for your goldilocks period, not too hot, not too cold, not too dense, not too thin, then you can presumably repeat the effort after some millions or billions of years, migrating to a new Universe. And you might be running on a clock too. Making a pocket Universe in science fiction tends to show us time running quickly there, so that we get billions of years unfolding in mere days, but there’s no reason to assume time would run faster in some Universe you spawned via induced Big Bang or hunted out of the Multiverse for travel too. Indeed there’s a lot of issues with trying to move to some place where the time isn’t running at about the same speed. As an example you might step through your portal to where the time goes a million times faster and just be torn apart by tidal effects. So if you have to wait to go there at the same time in your own Universe, getting in early is nice, and you might like faster expanding Universes, and just leave them for new ones if they thinned out too much. This probably counter-indicates our own Universe being such a thing though because our Cosmological Expansion appears to be accelerating, and you’d probably want the reverse, fast initial expansion dropping to a crawl, but there’s some big assumptions in there of course. Also, you would expect such a Universe to be thoroughly colonized by now, with a 13 billion year head start. The Fermi Paradox is already problematic enough normally when we just assume aliens might have a couple billion year head start from having evolved on a younger world than us. On the other hand, if you emerge into a Universe, even getting into it earlier during that Bathwater Epoch, if you haven’t got faster than light travel it's already too late to colonize it all, and you would have big pockets of space, like our own Observable Universe, that couldn’t even see your civilization and vice versa, so maybe we are in some Universe someone already colonized from nearly the beginning of time, and if it were possible for them to migrate Universes, it’s possible for us to as well, which might be one way we could escape ever having to be a Civilization at the End of Time. We’ll be getting to our Audiobook of the Month in just a moment but folks sometimes ask about the music we use, and it comes from a wide range of sources but some of you might have recognized today’s selection as coming from Stellardrone, who I happened to be listening to while writing the episode and thought it would make a good musical accompaniment for today, and I’ll link his work in the episode description as we usually do for the musicians and composers kind enough to lend us their work if you want to find some more of it. I may have been influenced by the music I was listening to but the episode was inspired by countless science fiction stories of ancient civilizations or those predating even the Universe itself, or trying to flee to another Universe, and both are themes in Stephen Baxter’s famous Xeelee Sequence, the first novel of which, “Raft†features future humans trying to survive after traveling to an alternate universe with different physical constants, something we discussed today. Raft is Baxter’s debut Novel, and begins his reputation for being not only one of the most imaginative science fiction authors of modern times, but also one who sticks to hard science wherever possible, and in spite of this his Xeelee Sequence is one that spans eons of time and the breadth of the Universe while also conveying how enormous both truly are, and for this reason Raft is our January 2021 Audible Audiobook of the Month. If you would like to try out Raft, you can find that audiobook, along with the many other excellents stories by Stephen Baxter, over at Audible. They also have podcasts, guided-wellness programs, theatrical performances, and exclusive audible originals, indeed they have over three centuries worth of audio if you just hit the play button and ran it through every title. If you want access to that massive collection of great audiobooks, like “Raftâ€, you can join Audible for a 30-day free trial, and Audible members not only get discounts on any audiobooks they buy, but a free book every month, with a Premium Plus Membership. Additionally, they are now giving unlimited access to their audible originals. You can start listening today with a 30-day Audible free trial. Just visit the link in the episode description, Audible.com/Isaac, or text “Isaac†to 500-500. So welcome to 2021 and we have quite a schedule ahead for the year, starting next week with a look at Cryonics and what the ability to freeze people and revive them would mean for our civilization. We’ll follow that up with our Mid-Month weekend bonus episode, “Machine OVerlords & Post-Discontent Societies†on Sunday, January 17, then in two weeks we will return to the Alien Civilizations series for a look at Oceanic Aliens. If you want alerts when those and other episodes come out, make sure to subscribe to the channel, and if you’d like to help support future episodes, you can donate to us on Patreon, or our website, IsaacArthur.net, which are linked in the episode description below, along with all of our various social media forums where you can get updates and chat with others about the concepts in the episodes and many other futuristic ideas. You can also follow us itunes, Soundcloud, or Spotify to get our audio-only versions of the show. Until next time, thanks for watching, and have a great week! Today’s topic, Black hole Farming, is going to be a difficult one because it’s a video I probably shouldn’t have made without covering other topics first, and also because it draws heavily on quite a few other videos I did make first. So it essentially amounts to three topics that we need to cover today and assumes a knowledge of the most recent videos on the channel, which means that if this is your first visit to this channel, while I normally try to make videos as standalone as possible and you probably can watch this without watching the others first, it isn’t advised. That said, it isn’t absolutely necessary and to help with that, whenever I bring up topics we’ve covered in more detail in other videos you will usually see an in-video link for that video pop up, and you can just click on it to pause this video and watch that one. You can also turn on the closed caption subtitles if you are having problems understanding me. So I said it was actually three topics, not just one, for today. What are those three topics? Well let’s list them out. 1) Using Black Holes for Power Sources We’ve talked about this before but mostly in the context of Hawking Radiation from small, artificial black holes. Today’s video is focused on large, long-lived black holes, where Hawking Radiation is incredibly tiny and other methods are needed. So we’ll be discussing those other methods as well as what the implications of living on minimal Hawking Radiation would be like 2) The Fate of the Universe In this section we’ll go over the timeline of ages of the Universe fairly quickly, and also quickly cover some of the other ideas for Civilizations far in the future, which we may expand on in future videos. 3) Black Hole Farming In the last section we’ll get into the meat of things, trying to contemplate what civilizations would be like that essentially fed themselves off black holes. It’s the concept of using black holes as the power source for your civilization, and actually creating or placing black holes to make that work best, which is the origin of the title. I think it summons to mind the image of farmer in coveralls with a pitchfork literally farming black holes but we’re sticking with it anyway. So without further ado, let’s dig in. Our first topic, using Black Holes as power sources is, as I mentioned, something we looked at before in the twin videos discussing Hawking Radiation, Micro-Black Holes, and using them to power starships. You may want to watch those, or re-watch those, before proceeding, but the quick summary is that Black Holes are thought to emit Hawking Radiation loosely in proportion to their size. Except backwards from what you’d expect, the giant monster sized ones in the centers of galaxies emit so little of it you’d need a trillion, trillion years to collect enough energy to turn on a little LED light for a fraction of a second. Alternatively the small ones gush out power so fast they burn out their tiny mass in very short times. There’s two upshots of this. First, that the lifespan of black holes is proportional to the cube of the mass, one twice as massive emits only a quarter of the power and lives eight times longer, one ten times as massive emits a hundredth of the power and lives a thousand times as long, etc. Second, if we can make artificial black holes, and especially if we can feed matter into them to replace what they lose to Hawking Radiation, we have an excellent power source for things. Black Holes are roughly on par with anti-matter, and vastly better than nuclear fission or fusion, in terms of energy per unit-mass of fuel, and they don’t blow up unless you starve them to death, a process that would take years or centuries normally, making them a very attractive option for power generation and storage. This is assuming we can figure out how to make small ones and feed them, both of which are actually a lot harder than with their bigger, naturally occurring kindred. Which again emit virtually no energy on timelines that can be measured without using scientific notation. This doesn’t mean we can’t tap black holes for power in other ways though. The preferred way to tap a black hole for power quickly, which also works on neutron stars, is to suck out their rotational energy. Stars spin, same as planets, they have a lot of angular momentum and that is one of those conserved quantities in nature. When they die and collapse they start spinning much faster for the same reason an ice skater twirling around with her arms out will spin much faster by just bringing her arms in toward her body. Our sun rotates around once a month, neutrons stars often rotate many times a second, that is why pulsars make such handy clocks. I was going to say pulsars are a type of neutron star but all neutron stars begin as pulsars, it’s just they have to be pointing in our direction for us to notice the pulsing and that effect diminishes with time. This isn’t a video on pulsars so I’ll just simplify it for the moment by saying they emit two narrow beams from opposite directions and if you’re at the right angle each of those beams will pass over you every time it spins around, which again is many times a second. They only do this for the first hundred or so million years of their life, and only about a tenth happen to line up with Earth so it is right to think of pulsars as a type of neutron star it’s just that the type is A) Fairly young and B) coincidentally aimed our way. Every neutron star was a pulsar for someone at some point. Science fiction loves to say you can use pulsars to get navigational fixes off of, and that’s basically true, but you’d need a catalog of all the young neutron stars to do that properly. And again it is only young neutrons stars you can use for this as they slowly lose energy and cool with time, something we’ll discuss a bit more in the second section of this video. Anyway needless to say black holes spin too, and very quickly, and both them and neutron stars emit huge magnetic fields as a result, same as Earth does from having a giant molten ball of spinning metal in the core. You can tap that power, sucking energy from spinning magnets was how the first electric generator worked, the Faraday Disc, which was the precursor of dynamos. The disc slowed down as it leaked power as electricity. Stealing away that black holes rotational energy, which is a large chunk of it’s total mass energy, is thus a pretty attractive option. And there’s various proposed ways of doing that. The Penrose process is probably the best known of them, and relies on being able to remove that energy because a black holes rotational energy is thought to be stored just outside the event horizon in what’s called the ergosphere. You obviously can’t dip under an event horizon and suck energy out, but we can from the ergosphere. There’s also the Blandford–Znajek process which is one of the lead candidates for explaining how quasars are powered. If you’re familiar with Quasars, and how they are brighter than most galaxies, this gives you an idea how much juice a black hole can provide. It also taps the Ergopshere for power and does it by using an accretion disc, so you’d use this on a black hole that already had one or that you were feeding, we’ll come back to that in a moment. You can also just dump matter into a black hole, it gains kinetic energy as it falls down, same as if we drop a rock off a tall building. If you tied a spool of thread to that rock and ran an axle through the spool attached to an electric generator you’d get electricity. And you could do the same with a black hole too. Of course if you drop that rock off the building you’d get less power than you’d expect because the rock is falling through air, slamming into air particles, and transferring much of its momentum to them, actually heating the air up in the process. This is how parachutes work, transferring all that kinetic energy into a wide swath of air as heat. It’s not a lot, but if the object is moving fast enough, like a spacecraft on re-entry, it’s a lot more and can make the object and the air it’s hitting so hot it will glow. You could gain some power with a solar panel that was nearby, drinking in that light. And you can do the same with a black hole because as matter falls towards them and often ends up in orbit around the black hole rather than directly entering, it forms what we call an accretion disk. And those glow quite brightly, giving off a lot of photons you can collect to use for power. If you dump matter into a black hole you can collect that power. It should be noted that when things approach large masses they usually don’t curve and slam down into them, and that’s as true for black holes as anything else. Their path curves, depending on how close they get and how massive they are. If they are very close to a very large mass they will hook right in, but normally they either fly off at a different angle or enter an orbit. And if there’s other stuff hanging around there for them to bump into their orbit will decay and they’ll eventually fall in. All that bumping, again, generates heat and if there’s enough heat, lots of visible light too, same as a red hot chunk of metal. That’s an accretion disc, for a black hole. And everything that falls into a black hole will add to its rotational energy too, though if it goes in backwards it will subtract from it. So if you’re dumping matter into black holes it pays to drop it in the right direction. Now neither the rock on a string or the solar panels collecting light off matter dumped into a black hole is terribly efficient as these things go, but they are a lot conceptually easier for some then the other methods I mentioned. Getting back to the Blandford–Znajek process, which I said was a prime candidate for how Quasars work and another black hole power method, and for our purposes it’s pretty similar to the penrose mechanism but happens to have an equation you can use to determine how much power you get out of the thing. They aren’t the same thing, and if you want to explore the difference I’ll attach a link in the video description to Serguei Komissarov’s 2008 paper that detailed the differences for those who are interested. That equation shows us that the power output of a black hole via this process goes with the square of the magnetic field strength of the accretion disc and the square of the Schwarzchild radius of the black hole, both of which will rise if we increase the size of that accretion disc or if we increase the mass of the black hole, and in nature bigger black holes usually have much larger accretion discs. Particularly the big ones near the center of galaxies, especially volatile young galaxies, as I mentioned this is usually considered a prime candidate for how quasars are powered and quasars frequently give off a hundred times the power of an entire regular galaxy. We would presumably want to tap that power a lot slower, using much smaller black holes and matter flow rates. Now any of the methods that involve extracting rotational energy will eventually cause that black hole to slow and finally stop rotating. At that point while you can still dump matter in, you won’t get nearly as a good a return, and the black holes mass will increase, making it live longer and give off less power via Hawking Radiation, which is the only option I’m familiar with that let’s you tap into the rest of that mass energy, as the black hole slowly evaporates. And we do want that energy. While lighter artificial black holes can emit useful sources of power via Hawking Radiation, the big massive ones essentially aren’t. Not unless you can build ridiculously sturdy equipment that can operate without wear or tear needing power or replacement matter to fix over even more ridiculously long periods of time. But we will have at least a hundred trillion years to get better at building sturdy material, and there aren’t many things around to cause external wear and tear by then, and it is the only game in town after you suck out the rotational energy and all the stars burn out, plus if you can do it there are some big potential advantages to waiting that long to pull out your energy, as we’ll discuss in part three. But first, let’s hit Part Two and review the Fate and Chronology of the Universe. Or I should say the primary current theory for a naturally aging and expanding universe. I mention that for two reasons. First that theory could be wrong, it probably is at least in part, or incomplete, and second because we don’t live in a universe that’s likely to continue along a natural path, because we live in it. Intelligent critters can change their environment after all, and generally tend to, and we’ve spent a lot of time on this channel talking about ways to tinker with planets, stars, and whole galaxies so it would seem silly to ignore how that could affect the progression of the Universe. So first we have the big bang, which doesn’t terribly interest us today, other than it being worth keeping in mind that the Universe began expanding then and continues to do so, and almost certainly has parts that are so far away from us that we will never detect any light from them since new space emerges between them and us faster than light can cover the distance. This effect will only get worse with time and eventually only the galaxies in our local area close enough to be bound to us by gravity will remain. As those galaxies get further away, and from all that emerging extra space seem to get further away faster and faster, the light from them red shifts and gets weaker and weaker. That’s not the only red-shifting light out there though, and there’s one type that is of great interest to us today for our final section. The Big Bang happened about 14 billion years ago, and just 400,000 years later an event called the last scattering took place. Not a long time, an eyeblink compared to the age of the Universe, but still a hundred times longer than recorded history and about the duration of human existence. The last scattering was an important event, and is aptly named. Up until then the universe was a much smaller and denser place. And small and dense means hot. Very hot, up until then the universe would have glowed like a star in every single direction you look, a big white haze. But the light emitted didn’t go far because it was too hot for atoms to form yet and it that pre-atomic plasma soup light scattered much easier. As the universe cooled down and suddenly atoms could form, and were further apart from expansion, photons could suddenly travel long distan |
