Module

FieldSpine.lean

Nyll.ClassFieldTheory.GlobalClassFieldTheory.IdealClassFieldTheory.RationalFiniteNormTransfer.FieldSpine
19 declarations indexed from sourceView source ↗

Fixed-field instance spine for rational finite-norm transport

This leaf names the finite-dimensional, scalar-tower, number-field, Galois, and quotient instances reused by the rational finite-norm transport modules. The public dependent type aliases are compiled once here.

Declarations

GlobalClassFieldTheory.IdealClassFieldTheory.RationalFiniteNormTransferInternal.ideleClassGroupIsMulCommutative

Shared commutativity proof for ordinary idèle class groups.

Source context 9 commands

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

noncomputable section
namespace GlobalClassFieldTheory
namespace IdealClassFieldTheory
open ClassFormation
open CyclicCohomology
section RationalIdeleExtension
open Reciprocity
open LocalClassFieldTheory
namespace RationalFiniteNormTransferInternal
theorem ideleClassGroupIsMulCommutative
    {F : Type} [Field F] [NumberField F] :
    IsMulCommutative (IdeleClassGroup F)
GlobalClassFieldTheory.IdealClassFieldTheory.RationalFiniteNormTransferInternal.fieldSpineIdeleClassGroupIsMulCommutative
Source context 9 commands

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

noncomputable section
namespace GlobalClassFieldTheory
namespace IdealClassFieldTheory
open ClassFormation
open CyclicCohomology
section RationalIdeleExtension
open Reciprocity
open LocalClassFieldTheory
namespace RationalFiniteNormTransferInternal
instance
    fieldSpineIdeleClassGroupIsMulCommutative
    {F : Type} [Field F] [NumberField F] :
    IsMulCommutative (IdeleClassGroup F)
GlobalClassFieldTheory.IdealClassFieldTheory.RationalFiniteNormTransferInternal.ideleClassSubgroupNormal

Shared normality proof for subgroups of ordinary idèle class groups.

Source context 10 commands

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

noncomputable section
namespace GlobalClassFieldTheory
namespace IdealClassFieldTheory
open ClassFormation
open CyclicCohomology
section RationalIdeleExtension
open Reciprocity
open LocalClassFieldTheory
namespace RationalFiniteNormTransferInternal
local instance
    fieldSpineIdeleClassGroupIsMulCommutative
    {F : Type} [Field F] [NumberField F] :
    IsMulCommutative (IdeleClassGroup F) :=
  ideleClassGroupIsMulCommutative
theorem ideleClassSubgroupNormal
    {F : Type} [Field F] [NumberField F]
    (N : Subgroup (IdeleClassGroup F)) : N.Normal
GlobalClassFieldTheory.IdealClassFieldTheory.RationalFiniteNormTransferInternal.fieldSpineIdeleClassSubgroupNormal
Source context 10 commands

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

noncomputable section
namespace GlobalClassFieldTheory
namespace IdealClassFieldTheory
open ClassFormation
open CyclicCohomology
section RationalIdeleExtension
open Reciprocity
open LocalClassFieldTheory
namespace RationalFiniteNormTransferInternal
local instance
    fieldSpineIdeleClassGroupIsMulCommutative
    {F : Type} [Field F] [NumberField F] :
    IsMulCommutative (IdeleClassGroup F) :=
  ideleClassGroupIsMulCommutative
instance
    fieldSpineIdeleClassSubgroupNormal
    {F : Type} [Field F] [NumberField F]
    (N : Subgroup (IdeleClassGroup F)) : N.Normal
GlobalClassFieldTheory.IdealClassFieldTheory.RationalFiniteNormTransferInternal.absoluteAlgebra

The canonical absolute algebra structure on a rational relative fixed field.

Source context 11 commands

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

noncomputable section
namespace GlobalClassFieldTheory
namespace IdealClassFieldTheory
open ClassFormation
open CyclicCohomology
section RationalIdeleExtension
open Reciprocity
open LocalClassFieldTheory
namespace RationalFiniteNormTransferInternal
local instance
    fieldSpineIdeleClassGroupIsMulCommutative
    {F : Type} [Field F] [NumberField F] :
    IsMulCommutative (IdeleClassGroup F) :=
  ideleClassGroupIsMulCommutative
local instance
    fieldSpineIdeleClassSubgroupNormal
    {F : Type} [Field F] [NumberField F]
    (N : Subgroup (IdeleClassGroup F)) : N.Normal :=
  ideleClassSubgroupNormal N
def absoluteAlgebra
    (K L : ClosedSubgroup
      (SeparableClosure ℚ ≃ₐ[ℚ] SeparableClosure ℚ))
    (hLK : L.toSubgroup ≤ K.toSubgroup) :
    Algebra ℚ
      (abstractRelativeFixedField ℚ (SeparableClosure ℚ) hLK)
GlobalClassFieldTheory.IdealClassFieldTheory.RationalFiniteNormTransferInternal.absoluteFinite
Source context 11 commands

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

noncomputable section
namespace GlobalClassFieldTheory
namespace IdealClassFieldTheory
open ClassFormation
open CyclicCohomology
section RationalIdeleExtension
open Reciprocity
open LocalClassFieldTheory
namespace RationalFiniteNormTransferInternal
local instance
    fieldSpineIdeleClassGroupIsMulCommutative
    {F : Type} [Field F] [NumberField F] :
    IsMulCommutative (IdeleClassGroup F) :=
  ideleClassGroupIsMulCommutative
local instance
    fieldSpineIdeleClassSubgroupNormal
    {F : Type} [Field F] [NumberField F]
    (N : Subgroup (IdeleClassGroup F)) : N.Normal :=
  ideleClassSubgroupNormal N
theorem absoluteFinite
    (K L : ClosedSubgroup
      (SeparableClosure ℚ ≃ₐ[ℚ] SeparableClosure ℚ))
    (hLK : L.toSubgroup ≤ K.toSubgroup)
    [hKfinite : Finite
      ((baseField
        (SeparableClosure ℚ ≃ₐ[ℚ] SeparableClosure ℚ)).toSubgroup ⧸
        extensionSubgroup
          (baseField
            (SeparableClosure ℚ ≃ₐ[ℚ] SeparableClosure ℚ))
          K (le_baseField K))]
    [hfinite : Finite
      (K.toSubgroup ⧸ extensionSubgroup K L hLK)] :
    Finite
      ((baseField
        (SeparableClosure ℚ ≃ₐ[ℚ] SeparableClosure ℚ)).toSubgroup ⧸
        extensionSubgroup
          (baseField
            (SeparableClosure ℚ ≃ₐ[ℚ] SeparableClosure ℚ))
          L (le_baseField L))
GlobalClassFieldTheory.IdealClassFieldTheory.RationalFiniteNormTransferInternal.fixedFiniteDimensional

The finite-dimensional structure on a rational abstract fixed field.

Source context 11 commands

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

noncomputable section
namespace GlobalClassFieldTheory
namespace IdealClassFieldTheory
open ClassFormation
open CyclicCohomology
section RationalIdeleExtension
open Reciprocity
open LocalClassFieldTheory
namespace RationalFiniteNormTransferInternal
local instance
    fieldSpineIdeleClassGroupIsMulCommutative
    {F : Type} [Field F] [NumberField F] :
    IsMulCommutative (IdeleClassGroup F) :=
  ideleClassGroupIsMulCommutative
local instance
    fieldSpineIdeleClassSubgroupNormal
    {F : Type} [Field F] [NumberField F]
    (N : Subgroup (IdeleClassGroup F)) : N.Normal :=
  ideleClassSubgroupNormal N
theorem fixedFiniteDimensional
    (K : ClosedSubgroup
      (SeparableClosure ℚ ≃ₐ[ℚ] SeparableClosure ℚ))
    [hKfinite : Finite
      ((baseField
        (SeparableClosure ℚ ≃ₐ[ℚ] SeparableClosure ℚ)).toSubgroup ⧸
        extensionSubgroup
          (baseField
            (SeparableClosure ℚ ≃ₐ[ℚ] SeparableClosure ℚ))
          K (le_baseField K))] :
    FiniteDimensional ℚ
      (abstractFixedField ℚ (SeparableClosure ℚ) K)
GlobalClassFieldTheory.IdealClassFieldTheory.RationalFiniteNormTransferInternal.relativeFiniteDimensional

The relative finite-dimensional structure on the fixed-field extension attached to an inclusion of closed subgroups.

Source context 11 commands

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

noncomputable section
namespace GlobalClassFieldTheory
namespace IdealClassFieldTheory
open ClassFormation
open CyclicCohomology
section RationalIdeleExtension
open Reciprocity
open LocalClassFieldTheory
namespace RationalFiniteNormTransferInternal
local instance
    fieldSpineIdeleClassGroupIsMulCommutative
    {F : Type} [Field F] [NumberField F] :
    IsMulCommutative (IdeleClassGroup F) :=
  ideleClassGroupIsMulCommutative
local instance
    fieldSpineIdeleClassSubgroupNormal
    {F : Type} [Field F] [NumberField F]
    (N : Subgroup (IdeleClassGroup F)) : N.Normal :=
  ideleClassSubgroupNormal N
theorem relativeFiniteDimensional
    (K L : ClosedSubgroup
      (SeparableClosure ℚ ≃ₐ[ℚ] SeparableClosure ℚ))
    (hLK : L.toSubgroup ≤ K.toSubgroup)
    [hKfinite : Finite
      ((baseField
        (SeparableClosure ℚ ≃ₐ[ℚ] SeparableClosure ℚ)).toSubgroup ⧸
        extensionSubgroup
          (baseField
            (SeparableClosure ℚ ≃ₐ[ℚ] SeparableClosure ℚ))
          K (le_baseField K))]
    [hfinite : Finite
      (K.toSubgroup ⧸ extensionSubgroup K L hLK)] :
    FiniteDimensional
      (abstractFixedField ℚ (SeparableClosure ℚ) K)
      (abstractRelativeFixedField ℚ (SeparableClosure ℚ) hLK)
GlobalClassFieldTheory.IdealClassFieldTheory.RationalFiniteNormTransferInternal.relativeScalarTower

The canonical scalar tower on a rational relative fixed field.

Source context 11 commands

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

noncomputable section
namespace GlobalClassFieldTheory
namespace IdealClassFieldTheory
open ClassFormation
open CyclicCohomology
section RationalIdeleExtension
open Reciprocity
open LocalClassFieldTheory
namespace RationalFiniteNormTransferInternal
local instance
    fieldSpineIdeleClassGroupIsMulCommutative
    {F : Type} [Field F] [NumberField F] :
    IsMulCommutative (IdeleClassGroup F) :=
  ideleClassGroupIsMulCommutative
local instance
    fieldSpineIdeleClassSubgroupNormal
    {F : Type} [Field F] [NumberField F]
    (N : Subgroup (IdeleClassGroup F)) : N.Normal :=
  ideleClassSubgroupNormal N
theorem relativeScalarTower
    (K L : ClosedSubgroup
      (SeparableClosure ℚ ≃ₐ[ℚ] SeparableClosure ℚ))
    (hLK : L.toSubgroup ≤ K.toSubgroup) :
    IsScalarTower ℚ
      (abstractFixedField ℚ (SeparableClosure ℚ) K)
      (abstractRelativeFixedField ℚ (SeparableClosure ℚ) hLK)
GlobalClassFieldTheory.IdealClassFieldTheory.RationalFiniteNormTransferInternal.relativeAbsoluteFiniteDimensional

Absolute finite-dimensionality of a rational relative fixed field.

Source context 11 commands

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

noncomputable section
namespace GlobalClassFieldTheory
namespace IdealClassFieldTheory
open ClassFormation
open CyclicCohomology
section RationalIdeleExtension
open Reciprocity
open LocalClassFieldTheory
namespace RationalFiniteNormTransferInternal
local instance
    fieldSpineIdeleClassGroupIsMulCommutative
    {F : Type} [Field F] [NumberField F] :
    IsMulCommutative (IdeleClassGroup F) :=
  ideleClassGroupIsMulCommutative
local instance
    fieldSpineIdeleClassSubgroupNormal
    {F : Type} [Field F] [NumberField F]
    (N : Subgroup (IdeleClassGroup F)) : N.Normal :=
  ideleClassSubgroupNormal N
theorem relativeAbsoluteFiniteDimensional
    (K L : ClosedSubgroup
      (SeparableClosure ℚ ≃ₐ[ℚ] SeparableClosure ℚ))
    (hLK : L.toSubgroup ≤ K.toSubgroup)
    [hKfinite : Finite
      ((baseField
        (SeparableClosure ℚ ≃ₐ[ℚ] SeparableClosure ℚ)).toSubgroup ⧸
        extensionSubgroup
          (baseField
            (SeparableClosure ℚ ≃ₐ[ℚ] SeparableClosure ℚ))
          K (le_baseField K))]
    [hfinite : Finite
      (K.toSubgroup ⧸ extensionSubgroup K L hLK)] :
    FiniteDimensional ℚ
      (abstractRelativeFixedField ℚ (SeparableClosure ℚ) hLK)
GlobalClassFieldTheory.IdealClassFieldTheory.RationalFiniteNormTransferInternal.fixedNumberField

The number-field structure on a rational abstract fixed field.

Source context 11 commands

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

noncomputable section
namespace GlobalClassFieldTheory
namespace IdealClassFieldTheory
open ClassFormation
open CyclicCohomology
section RationalIdeleExtension
open Reciprocity
open LocalClassFieldTheory
namespace RationalFiniteNormTransferInternal
local instance
    fieldSpineIdeleClassGroupIsMulCommutative
    {F : Type} [Field F] [NumberField F] :
    IsMulCommutative (IdeleClassGroup F) :=
  ideleClassGroupIsMulCommutative
local instance
    fieldSpineIdeleClassSubgroupNormal
    {F : Type} [Field F] [NumberField F]
    (N : Subgroup (IdeleClassGroup F)) : N.Normal :=
  ideleClassSubgroupNormal N
theorem fixedNumberField
    (K : ClosedSubgroup
      (SeparableClosure ℚ ≃ₐ[ℚ] SeparableClosure ℚ))
    [hKfinite : Finite
      ((baseField
        (SeparableClosure ℚ ≃ₐ[ℚ] SeparableClosure ℚ)).toSubgroup ⧸
        extensionSubgroup
          (baseField
            (SeparableClosure ℚ ≃ₐ[ℚ] SeparableClosure ℚ))
          K (le_baseField K))] :
    NumberField (abstractFixedField ℚ (SeparableClosure ℚ) K)
GlobalClassFieldTheory.IdealClassFieldTheory.RationalFiniteNormTransferInternal.relativeNumberField

The number-field structure on a rational relative fixed field.

Source context 11 commands

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

noncomputable section
namespace GlobalClassFieldTheory
namespace IdealClassFieldTheory
open ClassFormation
open CyclicCohomology
section RationalIdeleExtension
open Reciprocity
open LocalClassFieldTheory
namespace RationalFiniteNormTransferInternal
local instance
    fieldSpineIdeleClassGroupIsMulCommutative
    {F : Type} [Field F] [NumberField F] :
    IsMulCommutative (IdeleClassGroup F) :=
  ideleClassGroupIsMulCommutative
local instance
    fieldSpineIdeleClassSubgroupNormal
    {F : Type} [Field F] [NumberField F]
    (N : Subgroup (IdeleClassGroup F)) : N.Normal :=
  ideleClassSubgroupNormal N
theorem relativeNumberField
    (K L : ClosedSubgroup
      (SeparableClosure ℚ ≃ₐ[ℚ] SeparableClosure ℚ))
    (hLK : L.toSubgroup ≤ K.toSubgroup)
    [hKfinite : Finite
      ((baseField
        (SeparableClosure ℚ ≃ₐ[ℚ] SeparableClosure ℚ)).toSubgroup ⧸
        extensionSubgroup
          (baseField
            (SeparableClosure ℚ ≃ₐ[ℚ] SeparableClosure ℚ))
          K (le_baseField K))]
    [hfinite : Finite
      (K.toSubgroup ⧸ extensionSubgroup K L hLK)] :
    NumberField
      (abstractRelativeFixedField ℚ (SeparableClosure ℚ) hLK)
GlobalClassFieldTheory.IdealClassFieldTheory.RationalFiniteNormTransferInternal.relativeIsGalois

The Galois structure on a normal rational relative fixed field.

Source context 11 commands

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

noncomputable section
namespace GlobalClassFieldTheory
namespace IdealClassFieldTheory
open ClassFormation
open CyclicCohomology
section RationalIdeleExtension
open Reciprocity
open LocalClassFieldTheory
namespace RationalFiniteNormTransferInternal
local instance
    fieldSpineIdeleClassGroupIsMulCommutative
    {F : Type} [Field F] [NumberField F] :
    IsMulCommutative (IdeleClassGroup F) :=
  ideleClassGroupIsMulCommutative
local instance
    fieldSpineIdeleClassSubgroupNormal
    {F : Type} [Field F] [NumberField F]
    (N : Subgroup (IdeleClassGroup F)) : N.Normal :=
  ideleClassSubgroupNormal N
theorem relativeIsGalois
    (K L : ClosedSubgroup
      (SeparableClosure ℚ ≃ₐ[ℚ] SeparableClosure ℚ))
    (hLK : L.toSubgroup ≤ K.toSubgroup)
    (hnormal : (extensionSubgroup K L hLK).Normal) :
    IsGalois
      (abstractFixedField ℚ (SeparableClosure ℚ) K)
      (abstractRelativeFixedField ℚ (SeparableClosure ℚ) hLK)
GlobalClassFieldTheory.IdealClassFieldTheory.fieldSpinePublicIdeleClassGroupIsMulCommutative
Source context 8 commands

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

noncomputable section
namespace GlobalClassFieldTheory
namespace IdealClassFieldTheory
open ClassFormation
open CyclicCohomology
section RationalIdeleExtension
open Reciprocity
open LocalClassFieldTheory
instance
    fieldSpinePublicIdeleClassGroupIsMulCommutative
    {F : Type} [Field F] [NumberField F] :
    IsMulCommutative (IdeleClassGroup F)
GlobalClassFieldTheory.IdealClassFieldTheory.fieldSpinePublicIdeleClassSubgroupNormal
Source context 9 commands

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

noncomputable section
namespace GlobalClassFieldTheory
namespace IdealClassFieldTheory
open ClassFormation
open CyclicCohomology
section RationalIdeleExtension
open Reciprocity
open LocalClassFieldTheory
local instance
    fieldSpinePublicIdeleClassGroupIsMulCommutative
    {F : Type} [Field F] [NumberField F] :
    IsMulCommutative (IdeleClassGroup F) :=
  RationalFiniteNormTransferInternal.ideleClassGroupIsMulCommutative
instance
    fieldSpinePublicIdeleClassSubgroupNormal
    {F : Type} [Field F] [NumberField F]
    (N : Subgroup (IdeleClassGroup F)) : N.Normal
GlobalClassFieldTheory.IdealClassFieldTheory.rationalFiniteNormTransferBaseIdeleClass

The fixed-field idele-class type used as the domain of rational finite-norm transport.

Source context 10 commands

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

noncomputable section
namespace GlobalClassFieldTheory
namespace IdealClassFieldTheory
open ClassFormation
open CyclicCohomology
section RationalIdeleExtension
open Reciprocity
open LocalClassFieldTheory
local instance
    fieldSpinePublicIdeleClassGroupIsMulCommutative
    {F : Type} [Field F] [NumberField F] :
    IsMulCommutative (IdeleClassGroup F) :=
  RationalFiniteNormTransferInternal.ideleClassGroupIsMulCommutative
local instance
    fieldSpinePublicIdeleClassSubgroupNormal
    {F : Type} [Field F] [NumberField F]
    (N : Subgroup (IdeleClassGroup F)) : N.Normal :=
  RationalFiniteNormTransferInternal.ideleClassSubgroupNormal N
abbrev rationalFiniteNormTransferBaseIdeleClass
    (K : ClosedSubgroup
      (SeparableClosure ℚ ≃ₐ[ℚ] SeparableClosure ℚ))
    [hKfinite : Finite
      ((baseField
        (SeparableClosure ℚ ≃ₐ[ℚ] SeparableClosure ℚ)).toSubgroup ⧸
        extensionSubgroup
          (baseField
            (SeparableClosure ℚ ≃ₐ[ℚ] SeparableClosure ℚ))
          K (le_baseField K))] : Type
GlobalClassFieldTheory.IdealClassFieldTheory.rationalFiniteNormTransferQuotientTarget

The additive ordinary idele-class norm quotient used as the target of rational finite-norm transport.

Source context 10 commands

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

noncomputable section
namespace GlobalClassFieldTheory
namespace IdealClassFieldTheory
open ClassFormation
open CyclicCohomology
section RationalIdeleExtension
open Reciprocity
open LocalClassFieldTheory
local instance
    fieldSpinePublicIdeleClassGroupIsMulCommutative
    {F : Type} [Field F] [NumberField F] :
    IsMulCommutative (IdeleClassGroup F) :=
  RationalFiniteNormTransferInternal.ideleClassGroupIsMulCommutative
local instance
    fieldSpinePublicIdeleClassSubgroupNormal
    {F : Type} [Field F] [NumberField F]
    (N : Subgroup (IdeleClassGroup F)) : N.Normal :=
  RationalFiniteNormTransferInternal.ideleClassSubgroupNormal N
abbrev rationalFiniteNormTransferQuotientTarget
    (K L : ClosedSubgroup
      (SeparableClosure ℚ ≃ₐ[ℚ] SeparableClosure ℚ))
    (hLK : L.toSubgroup ≤ K.toSubgroup)
    (hnormal : (extensionSubgroup K L hLK).Normal)
    [hKfinite : Finite
      ((baseField
        (SeparableClosure ℚ ≃ₐ[ℚ] SeparableClosure ℚ)).toSubgroup ⧸
        extensionSubgroup
          (baseField
            (SeparableClosure ℚ ≃ₐ[ℚ] SeparableClosure ℚ))
          K (le_baseField K))]
    [hfinite : Finite
      (K.toSubgroup ⧸ extensionSubgroup K L hLK)] : Type
GlobalClassFieldTheory.IdealClassFieldTheory.RationalFiniteNormTransferInternal.quotientTargetZero

The canonical additive zero on the named finite-norm transfer target. Naming this instance prevents repeated typeclass reduction of the dependent fixed-field quotient.

Source context 11 commands

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

noncomputable section
namespace GlobalClassFieldTheory
namespace IdealClassFieldTheory
open ClassFormation
open CyclicCohomology
section RationalIdeleExtension
open Reciprocity
open LocalClassFieldTheory
local instance
    fieldSpinePublicIdeleClassGroupIsMulCommutative
    {F : Type} [Field F] [NumberField F] :
    IsMulCommutative (IdeleClassGroup F) :=
  RationalFiniteNormTransferInternal.ideleClassGroupIsMulCommutative
local instance
    fieldSpinePublicIdeleClassSubgroupNormal
    {F : Type} [Field F] [NumberField F]
    (N : Subgroup (IdeleClassGroup F)) : N.Normal :=
  RationalFiniteNormTransferInternal.ideleClassSubgroupNormal N
namespace RationalFiniteNormTransferInternal
def quotientTargetZero
    (K L : ClosedSubgroup
      (SeparableClosure ℚ ≃ₐ[ℚ] SeparableClosure ℚ))
    (hLK : L.toSubgroup ≤ K.toSubgroup)
    (hnormal : (extensionSubgroup K L hLK).Normal)
    [hKfinite : Finite
      ((baseField
        (SeparableClosure ℚ ≃ₐ[ℚ] SeparableClosure ℚ)).toSubgroup ⧸
        extensionSubgroup
          (baseField
            (SeparableClosure ℚ ≃ₐ[ℚ] SeparableClosure ℚ))
          K (le_baseField K))]
    [hfinite : Finite
      (K.toSubgroup ⧸ extensionSubgroup K L hLK)] :
    Zero (rationalFiniteNormTransferQuotientTarget
      K L hLK hnormal)
GlobalClassFieldTheory.IdealClassFieldTheory.rationalFiniteNormTransferExtensionIdeleClass

The ordinary idele-class type of the upper fixed field in a rational finite-norm transfer.

Source context 10 commands

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

noncomputable section
namespace GlobalClassFieldTheory
namespace IdealClassFieldTheory
open ClassFormation
open CyclicCohomology
section RationalIdeleExtension
open Reciprocity
open LocalClassFieldTheory
local instance
    fieldSpinePublicIdeleClassGroupIsMulCommutative
    {F : Type} [Field F] [NumberField F] :
    IsMulCommutative (IdeleClassGroup F) :=
  RationalFiniteNormTransferInternal.ideleClassGroupIsMulCommutative
local instance
    fieldSpinePublicIdeleClassSubgroupNormal
    {F : Type} [Field F] [NumberField F]
    (N : Subgroup (IdeleClassGroup F)) : N.Normal :=
  RationalFiniteNormTransferInternal.ideleClassSubgroupNormal N
abbrev rationalFiniteNormTransferExtensionIdeleClass
    (K L : ClosedSubgroup
      (SeparableClosure ℚ ≃ₐ[ℚ] SeparableClosure ℚ))
    (hLK : L.toSubgroup ≤ K.toSubgroup)
    [hKfinite : Finite
      ((baseField
        (SeparableClosure ℚ ≃ₐ[ℚ] SeparableClosure ℚ)).toSubgroup ⧸
        extensionSubgroup
          (baseField
            (SeparableClosure ℚ ≃ₐ[ℚ] SeparableClosure ℚ))
          K (le_baseField K))]
    [hfinite : Finite
      (K.toSubgroup ⧸ extensionSubgroup K L hLK)] : Type