Module

ConjugationNaturality.lean

Nyll.ClassFieldTheory.LocalClassFieldTheory.Finite.LocalReciprocity.ConjugationNaturality
7 declarations indexed from sourceView source ↗

Conjugation naturality of finite local reciprocity

Two realizations of a finite Galois extension inside the fixed separable closure are related by conjugation. This module transports that conjugation to the actual Galois group, records the algebraic norm-residue square, and bundles the resulting map on the topological abelianization continuously.

Declarations

LocalClassFieldTheory.abelianizedGaloisConjugationOfEmbeddings

Conjugation between two separable-closure realizations, transported to the abelianization of the actual relative Galois group.

Source context 5 commands

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

noncomputable section
namespace LocalClassFieldTheory
open scoped ValuativeRel
open LocalFieldTheory
variable (K L : Type) [Field K] [Field L] [Algebra K L]
  [FiniteDimensional K L] [IsGalois K L]
def abelianizedGaloisConjugationOfEmbeddings
    (i j : L →ₐ[K] SeparableClosure K) :
    Abelianization (Gal(L / K)) ≃* Abelianization (Gal(L / K))
LocalClassFieldTheory.abelianizedGaloisConjugationOfEmbeddings_eq_refl

After both realizations are identified with the actual extension, the transported conjugation is the identity on the abelianization.

Source context 5 commands

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

noncomputable section
namespace LocalClassFieldTheory
open scoped ValuativeRel
open LocalFieldTheory
variable (K L : Type) [Field K] [Field L] [Algebra K L]
  [FiniteDimensional K L] [IsGalois K L]
theorem abelianizedGaloisConjugationOfEmbeddings_eq_refl
    (i j : L →ₐ[K] SeparableClosure K) :
    abelianizedGaloisConjugationOfEmbeddings K L i j =
      MulEquiv.refl (Abelianization (Gal(L / K)))
LocalClassFieldTheory.concreteNormResidueSymbolOfEmbedding_conjugation

Algebraic conjugation naturality for the norm-residue symbols computed from two explicit realizations of the same finite Galois extension.

Source context 5 commands

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

noncomputable section
namespace LocalClassFieldTheory
open scoped ValuativeRel
open LocalFieldTheory
variable (K L : Type) [Field K] [Field L] [Algebra K L]
  [FiniteDimensional K L] [IsGalois K L]
theorem concreteNormResidueSymbolOfEmbedding_conjugation
    (i j : L →ₐ[K] SeparableClosure K)
    (D : ClassFormation.DegreeData (Gal(SeparableClosure K/K)))
    (v : ClassFormation.ValuationData D
      (galoisAmbientUnitsRep K (SeparableClosure K)))
    (hcf : ClassFormation.SatisfiesClassFieldAxiom
      (galoisAmbientUnitsRep K (SeparableClosure K))) :
    (abelianizedGaloisConjugationOfEmbeddings K L i j).toMonoidHom.comp
        (concreteNormResidueSymbolOfEmbedding K L i D v hcf) =
      concreteNormResidueSymbolOfEmbedding K L j D v hcf
LocalClassFieldTheory.localArtinMonoidHom_conjugation

Field-facing algebraic form of the second naturality diagram for the canonical local class formation.

Source context 7 commands

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

noncomputable section
namespace LocalClassFieldTheory
open scoped ValuativeRel
open LocalFieldTheory
variable (K L : Type) [Field K] [Field L] [Algebra K L]
  [FiniteDimensional K L] [IsGalois K L]
section LocalAlgebraic
variable [ValuativeRel K] [TopologicalSpace K]
  [IsNonarchimedeanLocalField K]
theorem localArtinMonoidHom_conjugation
    (i j : L →ₐ[K] SeparableClosure K) :
    (abelianizedGaloisConjugationOfEmbeddings K L i j).toMonoidHom.comp
        (concreteNormResidueSymbolOfEmbedding K L i
          (localResidueDatum K) (localHenselianValuation K)
          (separableClosureUnits_isClassFormation K)) =
      concreteNormResidueSymbolOfEmbedding K L j
        (localResidueDatum K) (localHenselianValuation K)
        (separableClosureUnits_isClassFormation K)
LocalClassFieldTheory.topologicalAbelianizationConjugationOfEmbeddings

The conjugation of two realizations, bundled continuously on the topological abelianization of the finite Krull Galois group.

Source context 5 commands

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

noncomputable section
namespace LocalClassFieldTheory
open scoped ValuativeRel
open LocalFieldTheory
variable (K L : Type) [Field K] [Field L] [Algebra K L]
  [FiniteDimensional K L] [IsGalois K L]
def topologicalAbelianizationConjugationOfEmbeddings
    (i j : L →ₐ[K] SeparableClosure K) :
    TopologicalAbelianization (Gal(L / K)) ≃ₜ*
      TopologicalAbelianization (Gal(L / K))
LocalClassFieldTheory.topologicalAbelianizationConjugationOfEmbeddings_toMonoidHom

Forgetting topology identifies the bundled conjugation with the algebraic conjugation through the finite abelianization comparison.

Source context 5 commands

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

noncomputable section
namespace LocalClassFieldTheory
open scoped ValuativeRel
open LocalFieldTheory
variable (K L : Type) [Field K] [Field L] [Algebra K L]
  [FiniteDimensional K L] [IsGalois K L]
theorem topologicalAbelianizationConjugationOfEmbeddings_toMonoidHom
    (i j : L →ₐ[K] SeparableClosure K) :
    (topologicalAbelianization_finite_equiv K L).symm.toMonoidHom.comp
        (topologicalAbelianizationConjugationOfEmbeddings K L i j).toMonoidHom =
      (abelianizedGaloisConjugationOfEmbeddings K L i j).toMonoidHom.comp
        (topologicalAbelianization_finite_equiv K L).symm.toMonoidHom
LocalClassFieldTheory.localArtinMap_conjugation

The continuous local Artin map is equivariant for conjugation between two realizations of the finite Galois extension.

Source context 7 commands

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

noncomputable section
namespace LocalClassFieldTheory
open scoped ValuativeRel
open LocalFieldTheory
variable (K L : Type) [Field K] [Field L] [Algebra K L]
  [FiniteDimensional K L] [IsGalois K L]
section LocalContinuous
variable [ValuativeRel K] [TopologicalSpace K]
  [IsNonarchimedeanLocalField K]
theorem localArtinMap_conjugation
    (i j : L →ₐ[K] SeparableClosure K) :
    (ContinuousMonoidHom.toContinuousMonoidHom
        (topologicalAbelianizationConjugationOfEmbeddings K L i j)).comp
        (localArtinMap K L) =
      localArtinMap K L