Created
July 26, 2014 05:25
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<lkuper> is it equivalent to say that a function is invertible and that it's a bijection? | |
<shachaf> Yes. | |
<lkuper> ok :) | |
<shachaf> But you have to be careful if you have "functions" between more complicated structures. | |
<shachaf> In which case there might be more requirements on the inverse. But not with plain old functions. | |
<lkuper> ah. by ""functions" between more complicated structures", do you mean, like, some other kind of morphism? | |
<lkuper> (I'm dealing with plain old functions here, but curious) | |
<shachaf> Right. | |
<shachaf> E.g. you might care that the inverse of a continuous function is continuous, or something. | |
<lkuper> I see. so, maybe another way to say this is that, when dealing with sets, it turns out bijectivity and invertibility coincide, but invertibility is a more general concept and applies to fancier kinds of objects too | |
<lkuper> thanks for the insight :) | |
<shachaf> It kind of depends on how you define words, really. | |
<lkuper> haha, yeah | |
<shachaf> Probably you'd say "isomorphism" if you wanted to be really clear that you're talking about morphisms in some other category. | |
<shachaf> And you'd say "bijection" if you wanted to be clear that you just mean something between sets. |
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