Module

ResidueNorm.lean

Nyll.ClassFieldTheory.LocalClassFieldTheory.Finite.Unramified.ResidueNorm
8 declarations indexed from sourceView source ↗

Provides the public declarations in the LocalClassFieldTheory.Finite.Unramified.ResidueNorm Lean module.

Declarations

LocalClassFieldTheory.integerUnitsModPrincipalUnitsNormOfGaloisOfIsIntegralClosure

The integral-closure quotient norm on first principal-unit quotients in an unramified valuation extension. This is the the unramified norm calculation residue-unit quotient before the later U^1 lifting.

Source context 6 commands

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

noncomputable section
universe u
namespace LocalClassFieldTheory
open scoped ValuativeRel
open LocalFieldTheory
open LocalFieldTheory.IsNonarchimedeanLocalField
def integerUnitsModPrincipalUnitsNormOfGaloisOfIsIntegralClosure
    (K L : Type u)
    [Field K] [ValuativeRel K] [TopologicalSpace K] [IsNonarchimedeanLocalField K]
    [Field L] [ValuativeRel L] [TopologicalSpace L] [IsNonarchimedeanLocalField L]
    [Algebra K L] [FiniteDimensional K L] [IsGalois K L]
    [Valuation.HasExtension (ValuativeRel.valuation K) (ValuativeRel.valuation L)]
    [LocalFieldTheory.ValuativeExtension K L] [IsIntegralClosure 𝒪[L] 𝒪[K] L]
    [Module.Finite 𝒪[K] 𝒪[L]]
    [LocalFieldTheory.IsNonarchimedeanLocalField.IsUnramifiedValuedExtension K L] :
    IntegerUnitsModPrincipalUnits L →* IntegerUnitsModPrincipalUnits K
LocalClassFieldTheory.integerUnitsModPrincipalUnitsNormOfGaloisOfIsIntegralClosure_mk

States the theorem integerUnitsModPrincipalUnitsNormOfGaloisOfIsIntegralClosure_mk.

Source context 6 commands

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

noncomputable section
universe u
namespace LocalClassFieldTheory
open scoped ValuativeRel
open LocalFieldTheory
open LocalFieldTheory.IsNonarchimedeanLocalField
theorem integerUnitsModPrincipalUnitsNormOfGaloisOfIsIntegralClosure_mk
    (K L : Type u)
    [Field K] [ValuativeRel K] [TopologicalSpace K] [IsNonarchimedeanLocalField K]
    [Field L] [ValuativeRel L] [TopologicalSpace L] [IsNonarchimedeanLocalField L]
    [Algebra K L] [FiniteDimensional K L] [IsGalois K L]
    [Valuation.HasExtension (ValuativeRel.valuation K) (ValuativeRel.valuation L)]
    [LocalFieldTheory.ValuativeExtension K L] [IsIntegralClosure 𝒪[L] 𝒪[K] L]
    [Module.Finite 𝒪[K] 𝒪[L]]
    [LocalFieldTheory.IsNonarchimedeanLocalField.IsUnramifiedValuedExtension K L]
    (u : 𝒪[L]ˣ) :
    integerUnitsModPrincipalUnitsNormOfGaloisOfIsIntegralClosure K L
        (integerUnitsModPrincipalUnitsMk L u) =
      integerUnitsModPrincipalUnitsMk K (normIntegerUnits K L u)
LocalClassFieldTheory.residueUnitsMap_normIntegerUnits_eq_galoisGroup_residue_prod_of_isIntegralClosure

After extending the residue of the integer-unit norm back to 𝓀[L], it is the product of the integral-closure residue actions.

Source context 6 commands

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

noncomputable section
universe u
namespace LocalClassFieldTheory
open scoped ValuativeRel
open LocalFieldTheory
open LocalFieldTheory.IsNonarchimedeanLocalField
theorem residueUnitsMap_normIntegerUnits_eq_galoisGroup_residue_prod_of_isIntegralClosure
    (K L : Type u)
    [Field K] [ValuativeRel K] [TopologicalSpace K] [IsNonarchimedeanLocalField K]
    [Field L] [ValuativeRel L] [TopologicalSpace L] [IsNonarchimedeanLocalField L]
    [Algebra K L] [FiniteDimensional K L] [IsGalois K L]
    [Valuation.HasExtension (ValuativeRel.valuation K) (ValuativeRel.valuation L)]
    [LocalFieldTheory.ValuativeExtension K L] [IsIntegralClosure 𝒪[L] 𝒪[K] L]
    (u : 𝒪[L]ˣ) :
    residueUnitsMapOfValuationExtension K L
        (integerUnitsToResidueUnits K (normIntegerUnits K L u)) =
      Finset.univ.prod (fun σ : Gal(L / K) =>
        Units.mapEquiv
          (galoisGroupResidueFieldEquivOfIsIntegralClosure K L σ).toMulEquiv
          (integerUnitsToResidueUnits L u)) := by
  rw [residueUnitsMap_integerUnitsToResidueUnits K L (normIntegerUnits K L u)]
  rw [integerUnitsMap_normIntegerUnits_eq_galoisGroup_prod_of_isIntegralClosure K L u]
  rw [map_prod]
  apply Finset.prod_congr rfl
  intro σ _
  exact
    (galoisGroupResidueFieldEquivOfIsIntegralClosure_integerUnitsToResidueUnits
      K L σ u).symm
LocalClassFieldTheory.residueUnitsMap_normIntegerUnits_eq_galoisGroup_residue_algEquiv_prod_of_isIntegralClosure

AlgEquiv-typed form of residueUnitsMap_normIntegerUnits_eq_galoisGroup_residue_prod_of_isIntegralClosure.

Source context 6 commands

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

noncomputable section
universe u
namespace LocalClassFieldTheory
open scoped ValuativeRel
open LocalFieldTheory
open LocalFieldTheory.IsNonarchimedeanLocalField
theorem residueUnitsMap_normIntegerUnits_eq_galoisGroup_residue_algEquiv_prod_of_isIntegralClosure
    (K L : Type u)
    [Field K] [ValuativeRel K] [TopologicalSpace K] [IsNonarchimedeanLocalField K]
    [Field L] [ValuativeRel L] [TopologicalSpace L] [IsNonarchimedeanLocalField L]
    [Algebra K L] [FiniteDimensional K L] [IsGalois K L]
    [Valuation.HasExtension (ValuativeRel.valuation K) (ValuativeRel.valuation L)]
    [LocalFieldTheory.ValuativeExtension K L] [IsIntegralClosure 𝒪[L] 𝒪[K] L]
    (u : 𝒪[L]ˣ) :
    residueUnitsMapOfValuationExtension K L
        (integerUnitsToResidueUnits K (normIntegerUnits K L u)) =
      Finset.univ.prod (fun σ : Gal(L / K) =>
        Units.mapEquiv
          (galoisGroupResidueAlgEquivOfIsIntegralClosure K L σ).toMulEquiv
          (integerUnitsToResidueUnits L u)) := by
  rw [residueUnitsMap_normIntegerUnits_eq_galoisGroup_residue_prod_of_isIntegralClosure
    K L u]
  apply Finset.prod_congr rfl
  intro σ _
  apply Units.ext
  rfl
LocalClassFieldTheory.integerUnitsModPrincipalUnitsNormOfGaloisOfIsIntegralClosure_residue_algEquiv_base_extend

Quotient-level form of the residue product formula for the integer-unit norm.

Source context 6 commands

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

noncomputable section
universe u
namespace LocalClassFieldTheory
open scoped ValuativeRel
open LocalFieldTheory
open LocalFieldTheory.IsNonarchimedeanLocalField
theorem integerUnitsModPrincipalUnitsNormOfGaloisOfIsIntegralClosure_residue_algEquiv_base_extend
    (K L : Type u)
    [Field K] [ValuativeRel K] [TopologicalSpace K] [IsNonarchimedeanLocalField K]
    [Field L] [ValuativeRel L] [TopologicalSpace L] [IsNonarchimedeanLocalField L]
    [Algebra K L] [FiniteDimensional K L] [IsGalois K L]
    [Valuation.HasExtension (ValuativeRel.valuation K) (ValuativeRel.valuation L)]
    [LocalFieldTheory.ValuativeExtension K L] [IsIntegralClosure 𝒪[L] 𝒪[K] L]
    [Module.Finite 𝒪[K] 𝒪[L]]
    [LocalFieldTheory.IsNonarchimedeanLocalField.IsUnramifiedValuedExtension K L]
    (x : IntegerUnitsModPrincipalUnits L) :
    residueUnitsMapOfValuationExtension K L
        (integerUnitsModPrincipalUnitsEquivResidueUnits K
          (integerUnitsModPrincipalUnitsNormOfGaloisOfIsIntegralClosure K L x)) =
      Finset.univ.prod (fun σ : Gal(L / K) =>
        Units.mapEquiv
          (galoisGroupResidueAlgEquivOfIsIntegralClosure K L σ).toMulEquiv
          (integerUnitsModPrincipalUnitsEquivResidueUnits L x)) := by
  refine IntegerUnitsModPrincipalUnits.inductionOn
    (motive := fun x =>
      residueUnitsMapOfValuationExtension K L
          (integerUnitsModPrincipalUnitsEquivResidueUnits K
            (integerUnitsModPrincipalUnitsNormOfGaloisOfIsIntegralClosure K L x)) =
        Finset.univ.prod (fun σ : Gal(L / K) =>
          Units.mapEquiv
            (galoisGroupResidueAlgEquivOfIsIntegralClosure K L σ).toMulEquiv
            (integerUnitsModPrincipalUnitsEquivResidueUnits L x)))
    x ?_
  intro u
  rw [integerUnitsModPrincipalUnitsNormOfGaloisOfIsIntegralClosure_mk]
  rw [integerUnitsModPrincipalUnitsEquivResidueUnits_mk]
  rw [integerUnitsModPrincipalUnitsEquivResidueUnits_mk]
  exact
    residueUnitsMap_normIntegerUnits_eq_galoisGroup_residue_algEquiv_prod_of_isIntegralClosure
      K L u
LocalClassFieldTheory.integerUnitsModPrincipalUnitsNormOfGaloisOfIsIntegralClosure_residue_base_extend_eq_residueNorm

In the unramified valuation case, the integral-closure quotient norm agrees after base extension with the quotient-level finite residue norm model.

Source context 6 commands

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

noncomputable section
universe u
namespace LocalClassFieldTheory
open scoped ValuativeRel
open LocalFieldTheory
open LocalFieldTheory.IsNonarchimedeanLocalField
theorem
  integerUnitsModPrincipalUnitsNormOfGaloisOfIsIntegralClosure_residue_base_extend_eq_residueNorm
    (K L : Type u)
    [Field K] [ValuativeRel K] [TopologicalSpace K] [IsNonarchimedeanLocalField K]
    [Field L] [ValuativeRel L] [TopologicalSpace L] [IsNonarchimedeanLocalField L]
    [Algebra K L] [FiniteDimensional K L] [IsGalois K L]
    [Valuation.HasExtension (ValuativeRel.valuation K) (ValuativeRel.valuation L)]
    [LocalFieldTheory.ValuativeExtension K L] [IsIntegralClosure 𝒪[L] 𝒪[K] L]
    [Module.Finite 𝒪[K] 𝒪[L]]
    [LocalFieldTheory.IsNonarchimedeanLocalField.IsUnramifiedValuedExtension K L]
    (x : IntegerUnitsModPrincipalUnits L) :
    residueUnitsMapOfValuationExtension K L
        (integerUnitsModPrincipalUnitsEquivResidueUnits K
          (integerUnitsModPrincipalUnitsNormOfGaloisOfIsIntegralClosure K L x)) =
      residueUnitsMapOfValuationExtension K L
        (integerUnitsModPrincipalUnitsEquivResidueUnits K
          (integerUnitsModPrincipalUnitsResidueNormOfValuationExtension K L x))
LocalClassFieldTheory.integerUnitsModPrincipalUnitsNormOfGaloisOfIsIntegralClosure_eq_residueNorm_of_unramifiedValuation

In the unramified valuation case, the actual integral-closure quotient norm on 𝒪[L]ˣ/U_L¹ is the quotient-level finite-field residue norm model.

Source context 6 commands

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

noncomputable section
universe u
namespace LocalClassFieldTheory
open scoped ValuativeRel
open LocalFieldTheory
open LocalFieldTheory.IsNonarchimedeanLocalField
theorem
  integerUnitsModPrincipalUnitsNormOfGaloisOfIsIntegralClosure_eq_residueNorm_of_unramifiedValuation
    (K L : Type u)
    [Field K] [ValuativeRel K] [TopologicalSpace K] [IsNonarchimedeanLocalField K]
    [Field L] [ValuativeRel L] [TopologicalSpace L] [IsNonarchimedeanLocalField L]
    [Algebra K L] [FiniteDimensional K L] [IsGalois K L]
    [Valuation.HasExtension (ValuativeRel.valuation K) (ValuativeRel.valuation L)]
    [LocalFieldTheory.ValuativeExtension K L] [IsIntegralClosure 𝒪[L] 𝒪[K] L]
    [Module.Finite 𝒪[K] 𝒪[L]]
    [LocalFieldTheory.IsNonarchimedeanLocalField.IsUnramifiedValuedExtension K L] :
    integerUnitsModPrincipalUnitsNormOfGaloisOfIsIntegralClosure K L =
      integerUnitsModPrincipalUnitsResidueNormOfValuationExtension K L
LocalClassFieldTheory.integerUnitsModPrincipalUnitsNormOfGaloisOfIsIntegralClosure_surjective_of_unramifiedValuation

The actual integral-closure quotient norm on 𝒪[L]ˣ/U_L¹ is surjective in the unramified valuation case.

Source context 6 commands

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

noncomputable section
universe u
namespace LocalClassFieldTheory
open scoped ValuativeRel
open LocalFieldTheory
open LocalFieldTheory.IsNonarchimedeanLocalField
theorem
  integerUnitsModPrincipalUnitsNormOfGaloisOfIsIntegralClosure_surjective_of_unramifiedValuation
    (K L : Type u)
    [Field K] [ValuativeRel K] [TopologicalSpace K] [IsNonarchimedeanLocalField K]
    [Field L] [ValuativeRel L] [TopologicalSpace L] [IsNonarchimedeanLocalField L]
    [Algebra K L] [FiniteDimensional K L] [IsGalois K L]
    [Valuation.HasExtension (ValuativeRel.valuation K) (ValuativeRel.valuation L)]
    [LocalFieldTheory.ValuativeExtension K L] [IsIntegralClosure 𝒪[L] 𝒪[K] L]
    [Module.Finite 𝒪[K] 𝒪[L]]
    [LocalFieldTheory.IsNonarchimedeanLocalField.IsUnramifiedValuedExtension K L] :
    Function.Surjective
      (integerUnitsModPrincipalUnitsNormOfGaloisOfIsIntegralClosure K L)