Zulip Chat Archive

Stream: Is there code for X?

Topic: Finiteness of subalgebra of algebraic extensions of F_p


Chris Hughes (Apr 07 2022 at 12:10):

I'm trying to prove that a finitely generated subsemiring of an algebraic extension of Fp\mathbb{F}_p is finite. For this I think I need two facts.

1) finitely generated subalgebras of algebraic extensions are finite dimensional as a vector space
2) finite dimensional vector spaces over finite fields are finite

I think we must have both of these somewhere

Eric Rodriguez (Apr 07 2022 at 12:19):

docs#finite_dimensional.fintype_of_fintype for 2

Riccardo Brasca (Apr 07 2022 at 12:23):

For the first one you can use something like docs#power_basis.finite_dimensional

Riccardo Brasca (Apr 07 2022 at 12:24):

(if the extension is generated by a single element)

Eric Rodriguez (Apr 07 2022 at 12:25):

what about docs#is_noetherian.iff_fg?

Chris Hughes (Apr 07 2022 at 12:30):

Thanks. I've proved the lemma now.

Chris Hughes (Apr 07 2022 at 12:37):

That was the very last sorry in Ax-Grothendieck by the way so when I send the proof to @Joseph Hua he should have a full proof of Ax-Grothendieck

Johan Commelin (Apr 07 2022 at 13:09):

That's cool! Congrats!

Joseph Hua (Apr 07 2022 at 15:09):

It's incorporated wooo


Last updated: Dec 20 2023 at 11:08 UTC