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QC (in Berlin 7/29-??? w/ COVID

tfw a physicist says two lie groups are isomorphic when they mean their lie algebras are isomorphic

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@QiaochuYuan

idk if physicists know this but sometimes students read your papers and they get confused because you said a false thing about lie groups and who do they come to for help? me, motherfuckers

a general point of confusion is treating things that are isomorphic as equal

treating them as NOT equal can also be confusing tho lmao had a linear algebra book that confused the hell out of me bc it defined everything twice (once for linear maps and once for matrices)

Sep 28, 2020

when i switched from maths to physics the fact that physicists define ‘equal’ w.r.t. to, well, the actual physics, as opposed to shallow structural isomorphisms was very hard to grog

QC (in Berlin 7/29-??? w/ COVID

Sep 28, 2020

e.g. understanding the difference between a vector and a pseudo vector was very difficult or partial vs total derivative

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@QiaochuYuan

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