Module

ActualFiniteNormalizationInclusionSquare.lean

Nyll.EtaleFundamentalGroups.Inertia.ActualFiniteNormalizationInclusionSquare
2 declarations indexed from sourceView source ↗

Finite normalization inclusion squares

Factors the finite ambient inclusion through the original normalization and proves compatibility of this inclusion with restricted Galois automorphisms.

Declarations

EtaleFundamentalGroups.Inertia.actualFiniteNormalizationAmbientRingHom_factor

The literal finite-normalization inclusion factors the ambient inclusion.

Source context 5 commands

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

namespace EtaleFundamentalGroups.Inertia
open SchemeTheory
universe u v w
variable (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]
omit [IsFractionRing A K] [IsGalois K L] in
theorem actualFiniteNormalizationAmbientRingHom_factor (E : FiniteGaloisIntermediateField K L) :
    (normalizationAmbientRingHom A (CommAlgCat.of A L)).comp
        (finiteAbsoluteNormalizationRingMap A K L E) =
      actualFiniteNormalizationAmbientRingHom A K L E
EtaleFundamentalGroups.Inertia.actualFiniteNormalizationRestrictionRingHom_inclusion

The actual finite normalization restriction commutes with the literal inclusion into the original upper normalization.

Source context 5 commands

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

namespace EtaleFundamentalGroups.Inertia
open SchemeTheory
universe u v w
variable (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]
omit [IsFractionRing A K] [IsGalois K L] in
theorem actualFiniteNormalizationRestrictionRingHom_inclusion
    (E : FiniteGaloisIntermediateField K L) (σ : Gal(L/K)) :
    (finiteAbsoluteNormalizationRingMap A K L E).comp
        (actualFiniteNormalizationRestrictionRingHom A K L E σ) =
      (normalizationGaloisRingHom A K L σ).comp
        (finiteAbsoluteNormalizationRingMap A K L E)