Yamaguchi26AbfaithfulGalois.mixed_characteristic_properties_3_6
For each finite Galois extension of a mixed-characteristic discretely valued field, the conjugation action on the mod-p abelianization is faithful. Consequently its absolute Galois group is p-ab-faithful.
Source context 4 commands
Surrounding namespaces, section variables, and local commands at this declaration.
namespace Yamaguchi26AbfaithfulGalois
open KummerTheory ValuationTheory.DiscreteValuationField ProCGroups.Abelian
open ProCGroups.FiniteStepSolvableQuotients
universe u vLean source · statement
theorem mixed_characteristic_properties_3_6
(K : Type u) [Field K] [CharZero K]
(base : DVF.{u, v} K) (p : ℕ) [Fact p.Prime]
[CharP base.residueField p] :
(∀ (L : Type u) [Field L] [Algebra K L]
[FiniteDimensional K L] [IsGalois K L],
∀ τ : Gal(L/K),
(∀ z : abelianModPower Gal(AlgebraicClosure L/L) p,
relativeGaloisAbelianModPowerTransform K L p τ z = z) → τ = 1) ∧
IsSigmaAbFaithful {p} Gal(AlgebraicClosure K/K)