Module

PrimePowerCharacterDetection.lean

Nyll.Yamaguchi26AbfaithfulGalois.GroupTheory.PrimePowerCharacterDetection
1 declaration indexed from sourceView source ↗

Detecting prime-power divisibility by continuous characters

For a compact totally disconnected abelian group, failure to be a prime-power power is detected by a continuous character of prime-power order.

Declarations

Yamaguchi26AbfaithfulGalois.exists_primePower_character_of_not_pow

Failure of divisibility by a prime power is detected by a continuous character of prime-power order.

Source context 3 commands

Surrounding namespaces, section variables, and local commands at this declaration.

namespace Yamaguchi26AbfaithfulGalois
open ProCGroups ProCGroups.ProC ProCGroups.Abelian
universe u
theorem exists_primePower_character_of_not_pow
    {A : Type u} [CommGroup A] [TopologicalSpace A] [IsTopologicalGroup A]
    [CompactSpace A] [T2Space A] [TotallyDisconnectedSpace A]
    (p : ℕ) [Fact p.Prime] (s : ℕ) (a : A)
    (ha : ¬ ∃ b : A, b ^ (p ^ s) = a) :
    ∃ n : ℕ, 0 < n ∧ ∃ χ : A →ₜ* Multiplicative (ZMod (p ^ n)), χ a ≠ 1