this post was submitted on 01 Feb 2024
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[–] OccamsTeapot@lemmy.world 2 points 7 months ago (1 children)

Mathematicians write the most insane shit you've ever seen in your life then they're just like □ peace out

[–] bonus_crab@lemmy.world 1 points 7 months ago (1 children)

If you wrote the equivalent of this in software I think linus torvalds himself would personally show up to destroy your pc.

[–] Aqarius@lemmy.world 2 points 7 months ago

Nah, formulas like that are basically the assembly code for logic.

[–] Sasha@lemmy.blahaj.zone 2 points 7 months ago (1 children)

OP, I need the definition for × and <,> too

[–] affiliate@lemmy.world 2 points 7 months ago (1 children)

× is the cartesian product and = {x, {x,y}} is the ordered pair of x and y. (i.e., if x is in X and y is in Y, then is the corresponding element of the cartesian product X × Y). hope this helps

[–] rasensprenger@feddit.de 0 points 7 months ago (1 children)

What does type() mean here?

[–] affiliate@lemmy.world 2 points 7 months ago (1 children)

it's the "order type" of a well ordering on a set. so, given a set X with a total ordering R, type(X,R) is the unique ordinal isomorphic to (X,R)

[–] bort@feddit.de 2 points 7 months ago (1 children)

what's with the square at the end? isn't that usually for proofs?

[–] affiliate@lemmy.world 1 points 7 months ago

yeah but sometimes when the textbook authors are feeling particularly mischievous they'll just put them in random places. and sometimes they'll even skip the proofs but keep the square.

[–] slampisko@lemmy.world 2 points 7 months ago

statements dreamed up by the utterly deranged

[–] Ragdoll_X@lemmy.world 1 points 7 months ago

Is this from Principia Mathematica or smth?

[–] hips_and_nips@lemmy.world 1 points 7 months ago (1 children)

This is giving me PTSD flashbacks from Number Theory at uni. What a fascinating mindfuck.

[–] affiliate@lemmy.world 0 points 7 months ago

oh god number theory.... the things they make you do in that class.......

[–] Pretzilla@lemmy.world 1 points 7 months ago
[–] yetAnotherUser@feddit.de 0 points 7 months ago