Module

ActualFiniteTameNormalizationMap.lean

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

Power normalization of finite tame values

Defines the ambient residue power map with exponent given by the ramification index divided by the tame order, and factors the canonical coordinate through it.

Declarations

EtaleFundamentalGroups.Inertia.actualFiniteTameNormalizationMap

The actual e/n normalization is the standard power endomorphism of the ambient residue monoid. It is constructed from the original index/order and is independent of any inertia element or character value.

Source context 5 commands

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

noncomputable section
namespace EtaleFundamentalGroups.Inertia
open SchemeTheory
universe u v w
variable (A : Type u) (K : Type v) (L : Type w)
  [CommRing A] [IsDomain A] [IsDiscreteValuationRing 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)) [Q.IsMaximal]
def actualFiniteTameNormalizationMap (E : FiniteGaloisIntermediateField K L) :
    Q.ResidueField →* Q.ResidueField
EtaleFundamentalGroups.Inertia.actualFiniteTameCoordinate_eq_normalizationMap

The SAME canonical coordinate factors through the independently constructed raw coefficient scalar and its actual normalization operation.

Source context 5 commands

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

noncomputable section
namespace EtaleFundamentalGroups.Inertia
open SchemeTheory
universe u v w
variable (A : Type u) (K : Type v) (L : Type w)
  [CommRing A] [IsDomain A] [IsDiscreteValuationRing 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)) [Q.IsMaximal]
theorem actualFiniteTameCoordinate_eq_normalizationMap
    (E : FiniteGaloisIntermediateField K L)
    (σ : actualNormalizationInertiaGroup A K L Q) :
    (((actualFiniteTameCoordinate A K L Q E).hom'.toFun σ).val).val =
      (actualFiniteTameNormalizationMap A K L Q E).toFun
        (actualFiniteRawTameValue A K L Q E σ)