Module

FinitePlaceTensorBlock.lean

Nyll.ClassFieldTheory.AlgebraicNumberTheory.Adele.FinitePlaceTensorBlock
12 declarations indexed from sourceView source ↗

Finite-place tensor factors as induced local blocks

This file is the finite-place counterpart of InfinitePlaceTensorBlock. It compares the concrete completion K_v used by the idele restricted product with the absolute-value completion used by the canonical local tensor decomposition, and records equivariance for conjugation on the second tensor factor.

Declarations

Base change from the absolute-value completion to the concrete adic completion commutes with conjugation on L.

Source context 8 commands

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

open scoped NumberField TensorProduct
open NumberField IsDedekindDomain
noncomputable section
open LocalClassFieldTheory
open AlgebraicNumberTheory.Valuations
open HilbertRamification
variable {K L : Type}
    [Field K] [NumberField K]
    [Field L] [NumberField L] [Algebra K L]
    [FiniteDimensional K L] [IsGalois K L]
omit [NumberField L] [FiniteDimensional K L] [IsGalois K L] in
theorem finitePlaceLocalTensorAlgEquiv_conjugation
    (v : HeightOneSpectrum (𝓞 K))
    (σ : L ≃ₐ[K] L)
    (z :
      LocalTensorAlgebra (L := L)
        (HeightOneSpectrum.adicAbv K v)) :
    finitePlaceLocalTensorAlgEquiv
        (K := K) (L := L) v
        (localTensorConjugation
          (K := K) (L := L)
          (HeightOneSpectrum.adicAbv K v) σ z) =
      scalarTensorConjugation
        (K := K) (L := L)
        (A := v.adicCompletion K) σ
        (finitePlaceLocalTensorAlgEquiv
          (K := K) (L := L) v z)

The finite-completion comparison on tensor units is equivariant.

Source context 8 commands

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

open scoped NumberField TensorProduct
open NumberField IsDedekindDomain
noncomputable section
open LocalClassFieldTheory
open AlgebraicNumberTheory.Valuations
open HilbertRamification
variable {K L : Type}
    [Field K] [NumberField K]
    [Field L] [NumberField L] [Algebra K L]
    [FiniteDimensional K L] [IsGalois K L]
omit [NumberField L] [FiniteDimensional K L] [IsGalois K L] in
theorem finitePlaceLocalTensorUnitsEquiv_smul
    (v : HeightOneSpectrum (𝓞 K))
    (σ : L ≃ₐ[K] L)
    (z :
      (LocalTensorAlgebra (L := L)
        (HeightOneSpectrum.adicAbv K v))ˣ) :
    letI :=
      localTensorUnitsAction
        (K := K) (L := L)
        (HeightOneSpectrum.adicAbv K v)
    letI :=
      scalarTensorUnitsAction
        (K := K) (L := L)
        (A := v.adicCompletion K)
    finitePlaceLocalTensorUnitsEquiv
        (K := K) (L := L) v (σ • z) =
      σ • finitePlaceLocalTensorUnitsEquiv
        (K := K) (L := L) v z := by
  let :=
    localTensorUnitsAction
      (K := K) (L := L)
      (HeightOneSpectrum.adicAbv K v)
  let :=
    scalarTensorUnitsAction
      (K := K) (L := L)
      (A := v.adicCompletion K)
  apply Units.ext
  exact finitePlaceLocalTensorAlgEquiv_conjugation
    (K := K) (L := L) v σ
      (z :
        LocalTensorAlgebra (L := L)
          (HeightOneSpectrum.adicAbv K v))

Equivariance of the inverse finite-completion comparison.

Source context 8 commands

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

open scoped NumberField TensorProduct
open NumberField IsDedekindDomain
noncomputable section
open LocalClassFieldTheory
open AlgebraicNumberTheory.Valuations
open HilbertRamification
variable {K L : Type}
    [Field K] [NumberField K]
    [Field L] [NumberField L] [Algebra K L]
    [FiniteDimensional K L] [IsGalois K L]
omit [NumberField L] [FiniteDimensional K L] [IsGalois K L] in
theorem finitePlaceLocalTensorUnitsEquiv_symm_smul
    (v : HeightOneSpectrum (𝓞 K))
    (σ : L ≃ₐ[K] L)
    (z : (v.adicCompletion K ⊗[K] L)ˣ) :
    letI :=
      localTensorUnitsAction
        (K := K) (L := L)
        (HeightOneSpectrum.adicAbv K v)
    letI :=
      scalarTensorUnitsAction
        (K := K) (L := L)
        (A := v.adicCompletion K)
    (finitePlaceLocalTensorUnitsEquiv
        (K := K) (L := L) v).symm (σ • z) =
      σ •
        (finitePlaceLocalTensorUnitsEquiv
          (K := K) (L := L) v).symm z := by
  let :=
    localTensorUnitsAction
      (K := K) (L := L)
      (HeightOneSpectrum.adicAbv K v)
  let :=
    scalarTensorUnitsAction
      (K := K) (L := L)
      (A := v.adicCompletion K)
  apply
    (finitePlaceLocalTensorUnitsEquiv
      (K := K) (L := L) v).injective
  rw [MulEquiv.apply_symm_apply,
    finitePlaceLocalTensorUnitsEquiv_smul,
    MulEquiv.apply_symm_apply]

The local tensor decomposition for the concrete finite component type used by relative ideles.

Source context 7 commands

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

open scoped NumberField TensorProduct
open NumberField IsDedekindDomain
noncomputable section
open LocalClassFieldTheory
open AlgebraicNumberTheory.Valuations
open HilbertRamification
variable {K L : Type}
    [Field K] [NumberField K]
    [Field L] [NumberField L] [Algebra K L]
    [FiniteDimensional K L] [IsGalois K L]
def finitePlaceTensorUnitsEquivLocalPlaceBlock
    (v : HeightOneSpectrum (𝓞 K))
    (w : AbsoluteValueExtension
      (HeightOneSpectrum.adicAbv K v) L) :
    letI :=
      decompositionGroupLocalUnitsAction
        (HeightOneSpectrum.adicAbv K v)
        (RayClass.adicAbv_isNontrivial v) w
    letI hK :=
      AbsoluteValue.extensionCompletionAlgebra
        (K := K) w.1
    letI : SMul K w.1.Completion := hK.toSMul
    letI :=
      AbsoluteValue.completionAlgebra
        (HeightOneSpectrum.adicAbv K v) w.1 w.2
    letI : ∀ w' : AbsoluteValueExtension
        (HeightOneSpectrum.adicAbv K v) L,
      Algebra
        (HeightOneSpectrum.adicAbv K v).Completion
        w'.1.Completion :=
      fun w' =>
        AbsoluteValue.completionAlgebra
          (HeightOneSpectrum.adicAbv K v)
          w'.1 w'.2
    (v.adicCompletion K ⊗[K] L)ˣ ≃*
      LocalPlaceBlock
        (HeightOneSpectrum.adicAbv K v)
        (RayClass.adicAbv_isNontrivial v) w :=
  (finitePlaceLocalTensorUnitsEquiv
      (K := K) (L := L) v).symm.trans
    (localTensorUnitsEquivLocalPlaceBlock
      (HeightOneSpectrum.adicAbv K v)
      (RayClass.adicAbv_isNontrivial v) w)
Source context 9 commands

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

open scoped NumberField TensorProduct
open NumberField IsDedekindDomain
noncomputable section
open LocalClassFieldTheory
open AlgebraicNumberTheory.Valuations
open HilbertRamification
variable {K L : Type}
    [Field K] [NumberField K]
    [Field L] [NumberField L] [Algebra K L]
    [FiniteDimensional K L] [IsGalois K L]
section Equivariance
variable
    (v : HeightOneSpectrum (𝓞 K))
    (w : AbsoluteValueExtension
      (HeightOneSpectrum.adicAbv K v) L)
instance finitePlaceDecompositionGroupAction :
    MulDistribMulAction
      (absoluteValueDecompositionGroup K w.1)
      (AlgebraicNumberTheory.Valuations.LocalizedCompletion
        (HeightOneSpectrum.adicAbv K v) w)ˣ
Source context 10 commands

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

open scoped NumberField TensorProduct
open NumberField IsDedekindDomain
noncomputable section
open LocalClassFieldTheory
open AlgebraicNumberTheory.Valuations
open HilbertRamification
variable {K L : Type}
    [Field K] [NumberField K]
    [Field L] [NumberField L] [Algebra K L]
    [FiniteDimensional K L] [IsGalois K L]
section Equivariance
variable
    (v : HeightOneSpectrum (𝓞 K))
    (w : AbsoluteValueExtension
      (HeightOneSpectrum.adicAbv K v) L)
local instance finitePlaceDecompositionGroupAction :
    MulDistribMulAction
      (absoluteValueDecompositionGroup K w.1)
      (AlgebraicNumberTheory.Valuations.LocalizedCompletion
        (HeightOneSpectrum.adicAbv K v) w)ˣ :=
  decompositionGroupLocalUnitsAction
    (HeightOneSpectrum.adicAbv K v)
    (RayClass.adicAbv_isNontrivial v) w
instance finitePlaceExtensionCompletionAlgebra :
    Algebra K w.1.Completion
Source context 11 commands

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

open scoped NumberField TensorProduct
open NumberField IsDedekindDomain
noncomputable section
open LocalClassFieldTheory
open AlgebraicNumberTheory.Valuations
open HilbertRamification
variable {K L : Type}
    [Field K] [NumberField K]
    [Field L] [NumberField L] [Algebra K L]
    [FiniteDimensional K L] [IsGalois K L]
section Equivariance
variable
    (v : HeightOneSpectrum (𝓞 K))
    (w : AbsoluteValueExtension
      (HeightOneSpectrum.adicAbv K v) L)
local instance finitePlaceDecompositionGroupAction :
    MulDistribMulAction
      (absoluteValueDecompositionGroup K w.1)
      (AlgebraicNumberTheory.Valuations.LocalizedCompletion
        (HeightOneSpectrum.adicAbv K v) w)ˣ :=
  decompositionGroupLocalUnitsAction
    (HeightOneSpectrum.adicAbv K v)
    (RayClass.adicAbv_isNontrivial v) w
local instance finitePlaceExtensionCompletionAlgebra :
    Algebra K w.1.Completion :=
  AbsoluteValue.extensionCompletionAlgebra (K := K) w.1
instance finitePlaceExtensionCompletionSMul :
    SMul K w.1.Completion
Source context 12 commands

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

open scoped NumberField TensorProduct
open NumberField IsDedekindDomain
noncomputable section
open LocalClassFieldTheory
open AlgebraicNumberTheory.Valuations
open HilbertRamification
variable {K L : Type}
    [Field K] [NumberField K]
    [Field L] [NumberField L] [Algebra K L]
    [FiniteDimensional K L] [IsGalois K L]
section Equivariance
variable
    (v : HeightOneSpectrum (𝓞 K))
    (w : AbsoluteValueExtension
      (HeightOneSpectrum.adicAbv K v) L)
local instance finitePlaceDecompositionGroupAction :
    MulDistribMulAction
      (absoluteValueDecompositionGroup K w.1)
      (AlgebraicNumberTheory.Valuations.LocalizedCompletion
        (HeightOneSpectrum.adicAbv K v) w)ˣ :=
  decompositionGroupLocalUnitsAction
    (HeightOneSpectrum.adicAbv K v)
    (RayClass.adicAbv_isNontrivial v) w
local instance finitePlaceExtensionCompletionAlgebra :
    Algebra K w.1.Completion :=
  AbsoluteValue.extensionCompletionAlgebra (K := K) w.1
local instance finitePlaceExtensionCompletionSMul :
    SMul K w.1.Completion :=
  (finitePlaceExtensionCompletionAlgebra v w).toSMul
instance finitePlaceLocalizedCompletionAlgebra :
    Algebra
      (HeightOneSpectrum.adicAbv K v).Completion
      w.1.Completion
Source context 13 commands

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

open scoped NumberField TensorProduct
open NumberField IsDedekindDomain
noncomputable section
open LocalClassFieldTheory
open AlgebraicNumberTheory.Valuations
open HilbertRamification
variable {K L : Type}
    [Field K] [NumberField K]
    [Field L] [NumberField L] [Algebra K L]
    [FiniteDimensional K L] [IsGalois K L]
section Equivariance
variable
    (v : HeightOneSpectrum (𝓞 K))
    (w : AbsoluteValueExtension
      (HeightOneSpectrum.adicAbv K v) L)
local instance finitePlaceDecompositionGroupAction :
    MulDistribMulAction
      (absoluteValueDecompositionGroup K w.1)
      (AlgebraicNumberTheory.Valuations.LocalizedCompletion
        (HeightOneSpectrum.adicAbv K v) w)ˣ :=
  decompositionGroupLocalUnitsAction
    (HeightOneSpectrum.adicAbv K v)
    (RayClass.adicAbv_isNontrivial v) w
local instance finitePlaceExtensionCompletionAlgebra :
    Algebra K w.1.Completion :=
  AbsoluteValue.extensionCompletionAlgebra (K := K) w.1
local instance finitePlaceExtensionCompletionSMul :
    SMul K w.1.Completion :=
  (finitePlaceExtensionCompletionAlgebra v w).toSMul
local instance finitePlaceLocalizedCompletionAlgebra :
    Algebra
      (HeightOneSpectrum.adicAbv K v).Completion
      w.1.Completion :=
  AbsoluteValue.completionAlgebra
    (HeightOneSpectrum.adicAbv K v) w.1 w.2
instance finitePlaceAllCompletionAlgebra
    (w' : AbsoluteValueExtension
      (HeightOneSpectrum.adicAbv K v) L) :
    Algebra
      (HeightOneSpectrum.adicAbv K v).Completion
      w'.1.Completion
Source context 14 commands

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

open scoped NumberField TensorProduct
open NumberField IsDedekindDomain
noncomputable section
open LocalClassFieldTheory
open AlgebraicNumberTheory.Valuations
open HilbertRamification
variable {K L : Type}
    [Field K] [NumberField K]
    [Field L] [NumberField L] [Algebra K L]
    [FiniteDimensional K L] [IsGalois K L]
section Equivariance
variable
    (v : HeightOneSpectrum (𝓞 K))
    (w : AbsoluteValueExtension
      (HeightOneSpectrum.adicAbv K v) L)
local instance finitePlaceDecompositionGroupAction :
    MulDistribMulAction
      (absoluteValueDecompositionGroup K w.1)
      (AlgebraicNumberTheory.Valuations.LocalizedCompletion
        (HeightOneSpectrum.adicAbv K v) w)ˣ :=
  decompositionGroupLocalUnitsAction
    (HeightOneSpectrum.adicAbv K v)
    (RayClass.adicAbv_isNontrivial v) w
local instance finitePlaceExtensionCompletionAlgebra :
    Algebra K w.1.Completion :=
  AbsoluteValue.extensionCompletionAlgebra (K := K) w.1
local instance finitePlaceExtensionCompletionSMul :
    SMul K w.1.Completion :=
  (finitePlaceExtensionCompletionAlgebra v w).toSMul
local instance finitePlaceLocalizedCompletionAlgebra :
    Algebra
      (HeightOneSpectrum.adicAbv K v).Completion
      w.1.Completion :=
  AbsoluteValue.completionAlgebra
    (HeightOneSpectrum.adicAbv K v) w.1 w.2
local instance finitePlaceAllCompletionAlgebra
    (w' : AbsoluteValueExtension
      (HeightOneSpectrum.adicAbv K v) L) :
    Algebra
      (HeightOneSpectrum.adicAbv K v).Completion
      w'.1.Completion :=
  AbsoluteValue.completionAlgebra
    (HeightOneSpectrum.adicAbv K v) w'.1 w'.2
instance finitePlaceScalarTensorUnitsAction :
    MulDistribMulAction
      (L ≃ₐ[K] L)
      (v.adicCompletion K ⊗[K] L)ˣ
Source context 15 commands

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

open scoped NumberField TensorProduct
open NumberField IsDedekindDomain
noncomputable section
open LocalClassFieldTheory
open AlgebraicNumberTheory.Valuations
open HilbertRamification
variable {K L : Type}
    [Field K] [NumberField K]
    [Field L] [NumberField L] [Algebra K L]
    [FiniteDimensional K L] [IsGalois K L]
section Equivariance
variable
    (v : HeightOneSpectrum (𝓞 K))
    (w : AbsoluteValueExtension
      (HeightOneSpectrum.adicAbv K v) L)
local instance finitePlaceDecompositionGroupAction :
    MulDistribMulAction
      (absoluteValueDecompositionGroup K w.1)
      (AlgebraicNumberTheory.Valuations.LocalizedCompletion
        (HeightOneSpectrum.adicAbv K v) w)ˣ :=
  decompositionGroupLocalUnitsAction
    (HeightOneSpectrum.adicAbv K v)
    (RayClass.adicAbv_isNontrivial v) w
local instance finitePlaceExtensionCompletionAlgebra :
    Algebra K w.1.Completion :=
  AbsoluteValue.extensionCompletionAlgebra (K := K) w.1
local instance finitePlaceExtensionCompletionSMul :
    SMul K w.1.Completion :=
  (finitePlaceExtensionCompletionAlgebra v w).toSMul
local instance finitePlaceLocalizedCompletionAlgebra :
    Algebra
      (HeightOneSpectrum.adicAbv K v).Completion
      w.1.Completion :=
  AbsoluteValue.completionAlgebra
    (HeightOneSpectrum.adicAbv K v) w.1 w.2
local instance finitePlaceAllCompletionAlgebra
    (w' : AbsoluteValueExtension
      (HeightOneSpectrum.adicAbv K v) L) :
    Algebra
      (HeightOneSpectrum.adicAbv K v).Completion
      w'.1.Completion :=
  AbsoluteValue.completionAlgebra
    (HeightOneSpectrum.adicAbv K v) w'.1 w'.2
local instance finitePlaceScalarTensorUnitsAction :
    MulDistribMulAction
      (L ≃ₐ[K] L)
      (v.adicCompletion K ⊗[K] L)ˣ :=
  scalarTensorUnitsAction
    (K := K) (L := L) (A := v.adicCompletion K)
instance finitePlaceLocalTensorUnitsAction :
    MulDistribMulAction
      (L ≃ₐ[K] L)
      (LocalTensorAlgebra (L := L)
        (HeightOneSpectrum.adicAbv K v))ˣ

The concrete finite-place local tensor decomposition is equivariant for the full global Galois action.

Source context 17 commands

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

open scoped NumberField TensorProduct
open NumberField IsDedekindDomain
noncomputable section
open LocalClassFieldTheory
open AlgebraicNumberTheory.Valuations
open HilbertRamification
variable {K L : Type}
    [Field K] [NumberField K]
    [Field L] [NumberField L] [Algebra K L]
    [FiniteDimensional K L] [IsGalois K L]
section Equivariance
variable
    (v : HeightOneSpectrum (𝓞 K))
    (w : AbsoluteValueExtension
      (HeightOneSpectrum.adicAbv K v) L)
local instance finitePlaceDecompositionGroupAction :
    MulDistribMulAction
      (absoluteValueDecompositionGroup K w.1)
      (AlgebraicNumberTheory.Valuations.LocalizedCompletion
        (HeightOneSpectrum.adicAbv K v) w)ˣ :=
  decompositionGroupLocalUnitsAction
    (HeightOneSpectrum.adicAbv K v)
    (RayClass.adicAbv_isNontrivial v) w
local instance finitePlaceExtensionCompletionAlgebra :
    Algebra K w.1.Completion :=
  AbsoluteValue.extensionCompletionAlgebra (K := K) w.1
local instance finitePlaceExtensionCompletionSMul :
    SMul K w.1.Completion :=
  (finitePlaceExtensionCompletionAlgebra v w).toSMul
local instance finitePlaceLocalizedCompletionAlgebra :
    Algebra
      (HeightOneSpectrum.adicAbv K v).Completion
      w.1.Completion :=
  AbsoluteValue.completionAlgebra
    (HeightOneSpectrum.adicAbv K v) w.1 w.2
local instance finitePlaceAllCompletionAlgebra
    (w' : AbsoluteValueExtension
      (HeightOneSpectrum.adicAbv K v) L) :
    Algebra
      (HeightOneSpectrum.adicAbv K v).Completion
      w'.1.Completion :=
  AbsoluteValue.completionAlgebra
    (HeightOneSpectrum.adicAbv K v) w'.1 w'.2
local instance finitePlaceScalarTensorUnitsAction :
    MulDistribMulAction
      (L ≃ₐ[K] L)
      (v.adicCompletion K ⊗[K] L)ˣ :=
  scalarTensorUnitsAction
    (K := K) (L := L) (A := v.adicCompletion K)
local instance finitePlaceLocalTensorUnitsAction :
    MulDistribMulAction
      (L ≃ₐ[K] L)
      (LocalTensorAlgebra (L := L)
        (HeightOneSpectrum.adicAbv K v))ˣ :=
  localTensorUnitsAction
    (K := K) (L := L)
    (HeightOneSpectrum.adicAbv K v)
omit [NumberField L] in
theorem finitePlaceTensorUnitsEquivLocalPlaceBlock_smul
    (σ : L ≃ₐ[K] L)
    (z : (v.adicCompletion K ⊗[K] L)ˣ) :
    finitePlaceTensorUnitsEquivLocalPlaceBlock
        (K := K) (L := L) v w (σ • z) =
      σ •
        finitePlaceTensorUnitsEquivLocalPlaceBlock
          (K := K) (L := L) v w z