Zulip Chat Archive

Stream: mathlib4

Topic: Galois theory of finite fields


Johan Commelin (Jan 06 2024 at 12:41):

How far are the main statements of Galois theory for finite fields from mathlib?

  • every extension of finite fields is Galois
  • the Galois group is cyclic
  • generated by Frobenius

Andrew Yang (Jan 06 2024 at 14:14):

I assume you mean finite extension (or at least algebraic)?
I think the folder FieldTheory/Finite/* is all we have in mathlib. We don't even know what Fq\overline{\mathbb{F}_q} is.

Johan Commelin (Jan 06 2024 at 14:16):

I meant L/K where both L and K are finite fields, so the extension will certainly be finite and algebraic.

Adam Topaz (Jan 06 2024 at 14:43):

I think we have all the ingredients to make these proofs relatively easy

Junyan Xu (Jan 06 2024 at 21:10):

Some work at https://leanprover.zulipchat.com/#narrow/stream/217875-Is-there-code-for-X.3F/topic/Algebraic.20Conjugate.20over.20Finite.20Fields/near/402812924 in Lean 3 that is not yet PR'd.

Andrew Yang (Jan 07 2024 at 05:29):

We have docs#GaloisField.instIsGalois


Last updated: May 02 2025 at 03:31 UTC