Module

ActualFiniteInertiaCoefficientRestriction.lean

Nyll.EtaleFundamentalGroups.Inertia.ActualFiniteInertiaCoefficientRestriction
1 declaration indexed from sourceView source ↗

Inertia under finite coefficient restriction

Transfers the ambient normalization inertia difference condition to the contracted finite normalization prime through the coefficient inclusion square.

Declarations

EtaleFundamentalGroups.Inertia.actualFiniteNormalizationRestriction_inertia_difference

Restriction of an actual ambient normalization inertia automorphism satisfies the inertia condition at the literal finite contraction. The coefficient square is proved by the actual restriction construction.

Source context 3 commands

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

namespace EtaleFundamentalGroups.Inertia
open SchemeTheory
universe u v w
theorem actualFiniteNormalizationRestriction_inertia_difference
    (A : Type u) (K : Type v) (L : Type w)
    [CommRing A] [Field K] [Field L]
    [Algebra A K] [IsFractionRing A K]
    [Algebra K L] [Algebra A L] [IsScalarTower A K L] [IsGalois K L]
    (Q : Ideal (normalizationCommAlgCat A L))
    (E : FiniteGaloisIntermediateField K L) (σ : Gal(L/K))
    (hσ : ∀ b : normalizationCommAlgCat A L,
      normalizationGaloisRingHom A K L σ b - b ∈ Q) :
    ∀ b : finiteAbsoluteNormalizationAlgebra A K L E,
      actualFiniteNormalizationRestrictionRingHom A K L E σ b - b ∈
        finiteAbsoluteNormalizationPrime A K L Q E