jamesamiller

Keybase proof

I hereby claim:

• I am jamesamiller on github.
• I am millerja (https://keybase.io/millerja) on keybase.
• I have a public key whose fingerprint is 06B1 8D7A FB64 382E 292B 858D EC72 8F76 E67A 0E67

To claim this, I am signing this object:

jamesamiller

\documentclass[crop=true, border=10pt]{standalone}
\usepackage{comment}
\begin{comment}
:Title: Attack from Andromeda
:Author: J A Miller (millerja@uah.edu), 2020/02/04

The Andromeda "paradox". Spacetime diagram for aliens launching an attack on Earth, according to three observers: one on the ground in the same frame as the aliens, and two walking past the first in opposite directions with the same speed.

References:

jamesamiller

\documentclass[crop=true, border=10pt]{standalone}
\usepackage{comment}
\begin{comment}
:Title:       Area preservation in the Lorentz Transformations
:Author: 	    J A Miller, UAH Physics & Astronomy, millerja@uah.edu
              2020/02/04

Plot to demonstrate how the Lorentz Transformation preserves area. Suppose the primed frame is moving in the $+x$ direction with speed $v$ relative to the unprimed frame.

Consider a unit square in the primed frame, with corners at $A^\prime =(x,t) =(0,0)$, $B^\prime =(0,1)$, $C^\prime =(1,1)$, and $D^\prime =(1,0)$. In the unprimed system, these points are transformed into $A = (0,0)$, $B = (\gamma v,\gamma)$, $C = (\gamma (1+v),\gamma (1+v))$, and $D = (\gamma,\gamma v)$, which outlines a parallelogram (in the unprimed coordinate system).

jamesamiller

\documentclass[crop=true, border=10pt]{standalone}
\usepackage{comment}
\begin{comment}
:Title: Spacetime diagrams
:Author: J A Miller (millerja@uah.edu), 2020/02/06

Generate spacetime or two-observer diagrams. 

Parameters can be set by the user. The distance between neighboring grid lines is one.

jamesamiller

\documentclass[crop=true, border=10pt]{standalone}
\usepackage{comment}
\begin{comment} 
:Title:          Two passing spaceships
:Author: 	    J A Miller, UAH Physics & Astronomy, millerja@uah.edu
                   2020/02/14

Two spaceships passing each other

The distance between neighboring grid lines is one.

jamesamiller

\documentclass[crop=true, border=10pt]{standalone}
\usepackage{comment}
\begin{comment} 
:Title: Tortoise and Hare - Variation 1
:Author: J A Miller (millerja@uah.edu), 2020/03/03

A race between a tortoise and hare. 

The distance between neighboring grid lines is one.

jamesamiller

\documentclass[crop=true, border=10pt]{standalone}
\usepackage{comment}
\begin{comment} 
:Title: Accelerated coordinate system
:Slug: Accelerated coordinates
:Tags:  special relativity
:Author: J A Miller, UAH Physics & Astronomy, millerja@uah.edu, 2020/05/12

Plot of accelerated coordinates $\xi$ and $\eta$ on an $x$-$t$ inertial spacetime.

jamesamiller

\documentclass[crop=true, border=10pt]{standalone}
\usepackage{comment}
\begin{comment} 
:Title: Motion of stars in the accelerated rocket frame
:Slug: Accelerated frame
:Tags:  special relativity
:Author: J A Miller, UAH Physics & Astronomy, millerja@uah.edu, 2020/05/12

Worldlines of stars in the accelerated rocket coordinates $\xi$ and $\eta$.

jamesamiller

\documentclass[crop=true, border=10pt]{standalone}
\usepackage{comment}
\begin{comment} 
:Title: Motion of another rocket in an accelerated rocket frame
:Slug: Accelerated frame
:Tags:  special relativity
:Author: J A Miller, UAH Physics & Astronomy, millerja@uah.edu, 2020/05/18

Worldlines of a test rocket in the accelerated coordinates $\xi$ and $\eta$ of an observer rocket. This illustrates that a constant proper distance requires different accelerations.

jamesamiller

\documentclass[crop=true, border=10pt]{standalone}
\usepackage{comment}
\begin{comment} 
:Title: Motion of stars in the accelerated rocket frame
:Slug: Rocket frame
:Tags:  special relativity
:Author: J A Miller, UAH Physics & Astronomy, millerja@uah.edu, 2020/05/12

Worldlines of stars and a rocket in the inertial $x$-$t$ frame, with light rays from one of
the stars to the rocket worldline.