Module

DecompositionFieldLocalization.lean

Nyll.ValuedFieldTheory.Ramification.HilbertRamification.DecompositionFieldLocalization
31 declarations indexed from sourceView source ↗

Decomposition-field value and residue comparison

This file identifies the decomposition field with the literal intersection L ∩ K_v inside the algebraic localization L_w. It then records the canonical residue-field isomorphism and equality of absolute-value ranges in the nonarchimedean case.

Declarations

HilbertRamification.proposition98CompletionBaseAlgebra
Source context 8 commands

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

noncomputable section
universe u v
namespace HilbertRamification
open AlgebraicNumberTheory.Valuations
variable {K : Type u} {L : Type v} [Field K] [Field L] [Algebra K L]
section LocalizationGalois
variable [IsGalois K L]
variable (vK : AbsoluteValue K ℝ) (hvK : vK.IsNontrivial)
  (w : AbsoluteValueExtension vK L)
instance proposition98CompletionBaseAlgebra : Algebra K w.1.Completion
HilbertRamification.proposition98CompletionBaseSMul
Source context 9 commands

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

noncomputable section
universe u v
namespace HilbertRamification
open AlgebraicNumberTheory.Valuations
variable {K : Type u} {L : Type v} [Field K] [Field L] [Algebra K L]
section LocalizationGalois
variable [IsGalois K L]
variable (vK : AbsoluteValue K ℝ) (hvK : vK.IsNontrivial)
  (w : AbsoluteValueExtension vK L)
local instance proposition98CompletionBaseAlgebra : Algebra K w.1.Completion :=
  AbsoluteValue.extensionCompletionAlgebra (K := K) w.1
instance proposition98CompletionBaseSMul : SMul K w.1.Completion
HilbertRamification.proposition98CompletionAlgebra
Source context 10 commands

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

noncomputable section
universe u v
namespace HilbertRamification
open AlgebraicNumberTheory.Valuations
variable {K : Type u} {L : Type v} [Field K] [Field L] [Algebra K L]
section LocalizationGalois
variable [IsGalois K L]
variable (vK : AbsoluteValue K ℝ) (hvK : vK.IsNontrivial)
  (w : AbsoluteValueExtension vK L)
local instance proposition98CompletionBaseAlgebra : Algebra K w.1.Completion :=
  AbsoluteValue.extensionCompletionAlgebra (K := K) w.1
local instance proposition98CompletionBaseSMul : SMul K w.1.Completion :=
  (AbsoluteValue.extensionCompletionAlgebra (K := K) w.1).toSMul
instance proposition98CompletionAlgebra : Algebra vK.Completion w.1.Completion
HilbertRamification.localization
Source context 11 commands

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

noncomputable section
universe u v
namespace HilbertRamification
open AlgebraicNumberTheory.Valuations
variable {K : Type u} {L : Type v} [Field K] [Field L] [Algebra K L]
section LocalizationGalois
variable [IsGalois K L]
variable (vK : AbsoluteValue K ℝ) (hvK : vK.IsNontrivial)
  (w : AbsoluteValueExtension vK L)
local instance proposition98CompletionBaseAlgebra : Algebra K w.1.Completion :=
  AbsoluteValue.extensionCompletionAlgebra (K := K) w.1
local instance proposition98CompletionBaseSMul : SMul K w.1.Completion :=
  (AbsoluteValue.extensionCompletionAlgebra (K := K) w.1).toSMul
local instance proposition98CompletionAlgebra : Algebra vK.Completion w.1.Completion :=
  AbsoluteValue.completionAlgebra vK w.1 w.2
abbrev localization : IntermediateField vK.Completion w.1.Completion
HilbertRamification.toLocalization
Source context 11 commands

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

noncomputable section
universe u v
namespace HilbertRamification
open AlgebraicNumberTheory.Valuations
variable {K : Type u} {L : Type v} [Field K] [Field L] [Algebra K L]
section LocalizationGalois
variable [IsGalois K L]
variable (vK : AbsoluteValue K ℝ) (hvK : vK.IsNontrivial)
  (w : AbsoluteValueExtension vK L)
local instance proposition98CompletionBaseAlgebra : Algebra K w.1.Completion :=
  AbsoluteValue.extensionCompletionAlgebra (K := K) w.1
local instance proposition98CompletionBaseSMul : SMul K w.1.Completion :=
  (AbsoluteValue.extensionCompletionAlgebra (K := K) w.1).toSMul
local instance proposition98CompletionAlgebra : Algebra vK.Completion w.1.Completion :=
  AbsoluteValue.completionAlgebra vK w.1 w.2
abbrev toLocalization : L →+* localization vK w
HilbertRamification.proposition98LocalizationBaseAlgebra
Source context 11 commands

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

noncomputable section
universe u v
namespace HilbertRamification
open AlgebraicNumberTheory.Valuations
variable {K : Type u} {L : Type v} [Field K] [Field L] [Algebra K L]
section LocalizationGalois
variable [IsGalois K L]
variable (vK : AbsoluteValue K ℝ) (hvK : vK.IsNontrivial)
  (w : AbsoluteValueExtension vK L)
local instance proposition98CompletionBaseAlgebra : Algebra K w.1.Completion :=
  AbsoluteValue.extensionCompletionAlgebra (K := K) w.1
local instance proposition98CompletionBaseSMul : SMul K w.1.Completion :=
  (AbsoluteValue.extensionCompletionAlgebra (K := K) w.1).toSMul
local instance proposition98CompletionAlgebra : Algebra vK.Completion w.1.Completion :=
  AbsoluteValue.completionAlgebra vK w.1 w.2
instance proposition98LocalizationBaseAlgebra : Algebra K (localization vK w)
HilbertRamification.proposition98LocalizationScalarTower
Source context 12 commands

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

noncomputable section
universe u v
namespace HilbertRamification
open AlgebraicNumberTheory.Valuations
variable {K : Type u} {L : Type v} [Field K] [Field L] [Algebra K L]
section LocalizationGalois
variable [IsGalois K L]
variable (vK : AbsoluteValue K ℝ) (hvK : vK.IsNontrivial)
  (w : AbsoluteValueExtension vK L)
local instance proposition98CompletionBaseAlgebra : Algebra K w.1.Completion :=
  AbsoluteValue.extensionCompletionAlgebra (K := K) w.1
local instance proposition98CompletionBaseSMul : SMul K w.1.Completion :=
  (AbsoluteValue.extensionCompletionAlgebra (K := K) w.1).toSMul
local instance proposition98CompletionAlgebra : Algebra vK.Completion w.1.Completion :=
  AbsoluteValue.completionAlgebra vK w.1 w.2
local instance proposition98LocalizationBaseAlgebra : Algebra K (localization vK w) :=
  ((algebraMap vK.Completion (localization vK w)).comp
    (algebraMap K vK.Completion)).toAlgebra
instance proposition98LocalizationScalarTower :
    IsScalarTower K vK.Completion (localization vK w)
HilbertRamification.decompositionField_toLocalizationAlgHom

The dense copy of L in the localization, as a K-algebra embedding for the scalar tower K → K_v → L_w.

Source context 13 commands

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

noncomputable section
universe u v
namespace HilbertRamification
open AlgebraicNumberTheory.Valuations
variable {K : Type u} {L : Type v} [Field K] [Field L] [Algebra K L]
section LocalizationGalois
variable [IsGalois K L]
variable (vK : AbsoluteValue K ℝ) (hvK : vK.IsNontrivial)
  (w : AbsoluteValueExtension vK L)
local instance proposition98CompletionBaseAlgebra : Algebra K w.1.Completion :=
  AbsoluteValue.extensionCompletionAlgebra (K := K) w.1
local instance proposition98CompletionBaseSMul : SMul K w.1.Completion :=
  (AbsoluteValue.extensionCompletionAlgebra (K := K) w.1).toSMul
local instance proposition98CompletionAlgebra : Algebra vK.Completion w.1.Completion :=
  AbsoluteValue.completionAlgebra vK w.1 w.2
local instance proposition98LocalizationBaseAlgebra : Algebra K (localization vK w) :=
  ((algebraMap vK.Completion (localization vK w)).comp
    (algebraMap K vK.Completion)).toAlgebra
local instance proposition98LocalizationScalarTower :
    IsScalarTower K vK.Completion (localization vK w) :=
  IsScalarTower.of_algebraMap_eq' (by
    ext x
    rfl)
def decompositionField_toLocalizationAlgHom :
    L →ₐ[K] localization vK w where
  __ := toLocalization vK w
  commutes' x := AbsoluteValue.toAlgebraicLocalization_algebraMap vK w.1 w.2 x
HilbertRamification.decompositionField_localization_adjoin_range_eq_top

The localization is generated over K_v by the subtype-valued copy of L, not only by its ambient-completion representatives.

Source context 14 commands

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

noncomputable section
universe u v
namespace HilbertRamification
open AlgebraicNumberTheory.Valuations
variable {K : Type u} {L : Type v} [Field K] [Field L] [Algebra K L]
section LocalizationGalois
variable [IsGalois K L]
variable (vK : AbsoluteValue K ℝ) (hvK : vK.IsNontrivial)
  (w : AbsoluteValueExtension vK L)
local instance proposition98CompletionBaseAlgebra : Algebra K w.1.Completion :=
  AbsoluteValue.extensionCompletionAlgebra (K := K) w.1
local instance proposition98CompletionBaseSMul : SMul K w.1.Completion :=
  (AbsoluteValue.extensionCompletionAlgebra (K := K) w.1).toSMul
local instance proposition98CompletionAlgebra : Algebra vK.Completion w.1.Completion :=
  AbsoluteValue.completionAlgebra vK w.1 w.2
local instance proposition98LocalizationBaseAlgebra : Algebra K (localization vK w) :=
  ((algebraMap vK.Completion (localization vK w)).comp
    (algebraMap K vK.Completion)).toAlgebra
local instance proposition98LocalizationScalarTower :
    IsScalarTower K vK.Completion (localization vK w) :=
  IsScalarTower.of_algebraMap_eq' (by
    ext x
    rfl)
omit [IsGalois K L] in
theorem decompositionField_localization_adjoin_range_eq_top :
    IntermediateField.adjoin vK.Completion
      (Set.range (toLocalization vK w)) = ⊤
HilbertRamification.decompositionField_toLocalization_isSeparable

Every generator coming from L is separable over K_v.

Source context 14 commands

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

noncomputable section
universe u v
namespace HilbertRamification
open AlgebraicNumberTheory.Valuations
variable {K : Type u} {L : Type v} [Field K] [Field L] [Algebra K L]
section LocalizationGalois
variable [IsGalois K L]
variable (vK : AbsoluteValue K ℝ) (hvK : vK.IsNontrivial)
  (w : AbsoluteValueExtension vK L)
local instance proposition98CompletionBaseAlgebra : Algebra K w.1.Completion :=
  AbsoluteValue.extensionCompletionAlgebra (K := K) w.1
local instance proposition98CompletionBaseSMul : SMul K w.1.Completion :=
  (AbsoluteValue.extensionCompletionAlgebra (K := K) w.1).toSMul
local instance proposition98CompletionAlgebra : Algebra vK.Completion w.1.Completion :=
  AbsoluteValue.completionAlgebra vK w.1 w.2
local instance proposition98LocalizationBaseAlgebra : Algebra K (localization vK w) :=
  ((algebraMap vK.Completion (localization vK w)).comp
    (algebraMap K vK.Completion)).toAlgebra
local instance proposition98LocalizationScalarTower :
    IsScalarTower K vK.Completion (localization vK w) :=
  IsScalarTower.of_algebraMap_eq' (by
    ext x
    rfl)
omit hvK in
theorem decompositionField_toLocalization_isSeparable (x : L) :
    IsSeparable vK.Completion (toLocalization vK w x)
HilbertRamification.decompositionField_toLocalization_minpoly_splits

Every generator coming from L has its K_v-minimal polynomial split inside the localization.

Source context 14 commands

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

noncomputable section
universe u v
namespace HilbertRamification
open AlgebraicNumberTheory.Valuations
variable {K : Type u} {L : Type v} [Field K] [Field L] [Algebra K L]
section LocalizationGalois
variable [IsGalois K L]
variable (vK : AbsoluteValue K ℝ) (hvK : vK.IsNontrivial)
  (w : AbsoluteValueExtension vK L)
local instance proposition98CompletionBaseAlgebra : Algebra K w.1.Completion :=
  AbsoluteValue.extensionCompletionAlgebra (K := K) w.1
local instance proposition98CompletionBaseSMul : SMul K w.1.Completion :=
  (AbsoluteValue.extensionCompletionAlgebra (K := K) w.1).toSMul
local instance proposition98CompletionAlgebra : Algebra vK.Completion w.1.Completion :=
  AbsoluteValue.completionAlgebra vK w.1 w.2
local instance proposition98LocalizationBaseAlgebra : Algebra K (localization vK w) :=
  ((algebraMap vK.Completion (localization vK w)).comp
    (algebraMap K vK.Completion)).toAlgebra
local instance proposition98LocalizationScalarTower :
    IsScalarTower K vK.Completion (localization vK w) :=
  IsScalarTower.of_algebraMap_eq' (by
    ext x
    rfl)
omit hvK in
theorem decompositionField_toLocalization_minpoly_splits (x : L) :
    ((minpoly vK.Completion (toLocalization vK w x)).map
      (algebraMap vK.Completion (localization vK w))).Splits
HilbertRamification.decompositionField_localization_normal

The algebraic localization of a Galois extension is normal over the completed base field, with no finite-degree hypothesis.

Source context 14 commands

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

noncomputable section
universe u v
namespace HilbertRamification
open AlgebraicNumberTheory.Valuations
variable {K : Type u} {L : Type v} [Field K] [Field L] [Algebra K L]
section LocalizationGalois
variable [IsGalois K L]
variable (vK : AbsoluteValue K ℝ) (hvK : vK.IsNontrivial)
  (w : AbsoluteValueExtension vK L)
local instance proposition98CompletionBaseAlgebra : Algebra K w.1.Completion :=
  AbsoluteValue.extensionCompletionAlgebra (K := K) w.1
local instance proposition98CompletionBaseSMul : SMul K w.1.Completion :=
  (AbsoluteValue.extensionCompletionAlgebra (K := K) w.1).toSMul
local instance proposition98CompletionAlgebra : Algebra vK.Completion w.1.Completion :=
  AbsoluteValue.completionAlgebra vK w.1 w.2
local instance proposition98LocalizationBaseAlgebra : Algebra K (localization vK w) :=
  ((algebraMap vK.Completion (localization vK w)).comp
    (algebraMap K vK.Completion)).toAlgebra
local instance proposition98LocalizationScalarTower :
    IsScalarTower K vK.Completion (localization vK w) :=
  IsScalarTower.of_algebraMap_eq' (by
    ext x
    rfl)
omit hvK in
theorem decompositionField_localization_normal :
    Normal vK.Completion (localization vK w)
HilbertRamification.decompositionField_localization_separable

The algebraic localization of a Galois extension is separable over the completed base field, with no finite-degree hypothesis.

Source context 14 commands

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

noncomputable section
universe u v
namespace HilbertRamification
open AlgebraicNumberTheory.Valuations
variable {K : Type u} {L : Type v} [Field K] [Field L] [Algebra K L]
section LocalizationGalois
variable [IsGalois K L]
variable (vK : AbsoluteValue K ℝ) (hvK : vK.IsNontrivial)
  (w : AbsoluteValueExtension vK L)
local instance proposition98CompletionBaseAlgebra : Algebra K w.1.Completion :=
  AbsoluteValue.extensionCompletionAlgebra (K := K) w.1
local instance proposition98CompletionBaseSMul : SMul K w.1.Completion :=
  (AbsoluteValue.extensionCompletionAlgebra (K := K) w.1).toSMul
local instance proposition98CompletionAlgebra : Algebra vK.Completion w.1.Completion :=
  AbsoluteValue.completionAlgebra vK w.1 w.2
local instance proposition98LocalizationBaseAlgebra : Algebra K (localization vK w) :=
  ((algebraMap vK.Completion (localization vK w)).comp
    (algebraMap K vK.Completion)).toAlgebra
local instance proposition98LocalizationScalarTower :
    IsScalarTower K vK.Completion (localization vK w) :=
  IsScalarTower.of_algebraMap_eq' (by
    ext x
    rfl)
omit hvK in
theorem decompositionField_localization_separable :
    Algebra.IsSeparable vK.Completion (localization vK w)
HilbertRamification.algebraicLocalization_isGalois

The algebraic localization of a Galois extension is Galois over K_v. This permits the fixed-field argument in infinite degree.

Source context 14 commands

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

noncomputable section
universe u v
namespace HilbertRamification
open AlgebraicNumberTheory.Valuations
variable {K : Type u} {L : Type v} [Field K] [Field L] [Algebra K L]
section LocalizationGalois
variable [IsGalois K L]
variable (vK : AbsoluteValue K ℝ) (hvK : vK.IsNontrivial)
  (w : AbsoluteValueExtension vK L)
local instance proposition98CompletionBaseAlgebra : Algebra K w.1.Completion :=
  AbsoluteValue.extensionCompletionAlgebra (K := K) w.1
local instance proposition98CompletionBaseSMul : SMul K w.1.Completion :=
  (AbsoluteValue.extensionCompletionAlgebra (K := K) w.1).toSMul
local instance proposition98CompletionAlgebra : Algebra vK.Completion w.1.Completion :=
  AbsoluteValue.completionAlgebra vK w.1 w.2
local instance proposition98LocalizationBaseAlgebra : Algebra K (localization vK w) :=
  ((algebraMap vK.Completion (localization vK w)).comp
    (algebraMap K vK.Completion)).toAlgebra
local instance proposition98LocalizationScalarTower :
    IsScalarTower K vK.Completion (localization vK w) :=
  IsScalarTower.of_algebraMap_eq' (by
    ext x
    rfl)
omit hvK in
theorem algebraicLocalization_isGalois :
    IsGalois vK.Completion (localization vK w)
HilbertRamification.decompositionField_completionImageSubfield

The copy of K_v as an actual subfield of the algebraic localization.

Source context 13 commands

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

noncomputable section
universe u v
namespace HilbertRamification
open AlgebraicNumberTheory.Valuations
variable {K : Type u} {L : Type v} [Field K] [Field L] [Algebra K L]
section LocalizationGalois
variable [IsGalois K L]
variable (vK : AbsoluteValue K ℝ) (hvK : vK.IsNontrivial)
  (w : AbsoluteValueExtension vK L)
local instance proposition98CompletionBaseAlgebra : Algebra K w.1.Completion :=
  AbsoluteValue.extensionCompletionAlgebra (K := K) w.1
local instance proposition98CompletionBaseSMul : SMul K w.1.Completion :=
  (AbsoluteValue.extensionCompletionAlgebra (K := K) w.1).toSMul
local instance proposition98CompletionAlgebra : Algebra vK.Completion w.1.Completion :=
  AbsoluteValue.completionAlgebra vK w.1 w.2
local instance proposition98LocalizationBaseAlgebra : Algebra K (localization vK w) :=
  ((algebraMap vK.Completion (localization vK w)).comp
    (algebraMap K vK.Completion)).toAlgebra
local instance proposition98LocalizationScalarTower :
    IsScalarTower K vK.Completion (localization vK w) :=
  IsScalarTower.of_algebraMap_eq' (by
    ext x
    rfl)
abbrev decompositionField_completionImageSubfield :
    Subfield (localization vK w)
HilbertRamification.decompositionField_decompositionField_eq_completionImage_comap

The decomposition-field extension comparison, comap form: an element of L lies in the decomposition field exactly when its image in L_w belongs to the embedded copy of K_v.

Source context 14 commands

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

noncomputable section
universe u v
namespace HilbertRamification
open AlgebraicNumberTheory.Valuations
variable {K : Type u} {L : Type v} [Field K] [Field L] [Algebra K L]
section LocalizationGalois
variable [IsGalois K L]
variable (vK : AbsoluteValue K ℝ) (hvK : vK.IsNontrivial)
  (w : AbsoluteValueExtension vK L)
local instance proposition98CompletionBaseAlgebra : Algebra K w.1.Completion :=
  AbsoluteValue.extensionCompletionAlgebra (K := K) w.1
local instance proposition98CompletionBaseSMul : SMul K w.1.Completion :=
  (AbsoluteValue.extensionCompletionAlgebra (K := K) w.1).toSMul
local instance proposition98CompletionAlgebra : Algebra vK.Completion w.1.Completion :=
  AbsoluteValue.completionAlgebra vK w.1 w.2
local instance proposition98LocalizationBaseAlgebra : Algebra K (localization vK w) :=
  ((algebraMap vK.Completion (localization vK w)).comp
    (algebraMap K vK.Completion)).toAlgebra
local instance proposition98LocalizationScalarTower :
    IsScalarTower K vK.Completion (localization vK w) :=
  IsScalarTower.of_algebraMap_eq' (by
    ext x
    rfl)
include hvK
theorem decompositionField_decompositionField_eq_completionImage_comap :
    (decompositionField_completionImageSubfield vK w).comap
        (toLocalization vK w) =
      (absoluteValueDecompositionField K w.1).toSubfield
HilbertRamification.decompositionField_decompositionField_image_eq_intersection

The decomposition-field extension comparison, literal intersection form inside L_w: the image of Z_w is the infimum of the images of L and K_v.

Source context 14 commands

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

noncomputable section
universe u v
namespace HilbertRamification
open AlgebraicNumberTheory.Valuations
variable {K : Type u} {L : Type v} [Field K] [Field L] [Algebra K L]
section LocalizationGalois
variable [IsGalois K L]
variable (vK : AbsoluteValue K ℝ) (hvK : vK.IsNontrivial)
  (w : AbsoluteValueExtension vK L)
local instance proposition98CompletionBaseAlgebra : Algebra K w.1.Completion :=
  AbsoluteValue.extensionCompletionAlgebra (K := K) w.1
local instance proposition98CompletionBaseSMul : SMul K w.1.Completion :=
  (AbsoluteValue.extensionCompletionAlgebra (K := K) w.1).toSMul
local instance proposition98CompletionAlgebra : Algebra vK.Completion w.1.Completion :=
  AbsoluteValue.completionAlgebra vK w.1 w.2
local instance proposition98LocalizationBaseAlgebra : Algebra K (localization vK w) :=
  ((algebraMap vK.Completion (localization vK w)).comp
    (algebraMap K vK.Completion)).toAlgebra
local instance proposition98LocalizationScalarTower :
    IsScalarTower K vK.Completion (localization vK w) :=
  IsScalarTower.of_algebraMap_eq' (by
    ext x
    rfl)
include hvK
theorem decompositionField_decompositionField_image_eq_intersection :
    (toLocalization vK w).fieldRange ⊓
        decompositionField_completionImageSubfield vK w =
      (absoluteValueDecompositionField K w.1).toSubfield.map
        (toLocalization vK w)
HilbertRamification.absoluteValueExtension_nonarchimedean_of_base

Nonarchimedeanness passes from the exact base valuation to its extension w; this uses only the bounded-natural-number definition.

Source context 16 commands

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

noncomputable section
universe u v
namespace HilbertRamification
open AlgebraicNumberTheory.Valuations
variable {K : Type u} {L : Type v} [Field K] [Field L] [Algebra K L]
section LocalizationGalois
variable [IsGalois K L]
variable (vK : AbsoluteValue K ℝ) (hvK : vK.IsNontrivial)
  (w : AbsoluteValueExtension vK L)
local instance proposition98CompletionBaseAlgebra : Algebra K w.1.Completion :=
  AbsoluteValue.extensionCompletionAlgebra (K := K) w.1
local instance proposition98CompletionBaseSMul : SMul K w.1.Completion :=
  (AbsoluteValue.extensionCompletionAlgebra (K := K) w.1).toSMul
local instance proposition98CompletionAlgebra : Algebra vK.Completion w.1.Completion :=
  AbsoluteValue.completionAlgebra vK w.1 w.2
local instance proposition98LocalizationBaseAlgebra : Algebra K (localization vK w) :=
  ((algebraMap vK.Completion (localization vK w)).comp
    (algebraMap K vK.Completion)).toAlgebra
local instance proposition98LocalizationScalarTower :
    IsScalarTower K vK.Completion (localization vK w) :=
  IsScalarTower.of_algebraMap_eq' (by
    ext x
    rfl)
include hvK
omit hvK
omit [IsGalois K L] in
theorem absoluteValueExtension_nonarchimedean_of_base
    (hv : LubinTate.Valuations.NonarchimedeanAbsoluteValue vK) :
    LubinTate.Valuations.NonarchimedeanAbsoluteValue w.1
HilbertRamification.decompositionField_decompositionField_nonarchimedean

Nonarchimedeanness also passes to the restriction of w to Z_w.

Source context 16 commands

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

noncomputable section
universe u v
namespace HilbertRamification
open AlgebraicNumberTheory.Valuations
variable {K : Type u} {L : Type v} [Field K] [Field L] [Algebra K L]
section LocalizationGalois
variable [IsGalois K L]
variable (vK : AbsoluteValue K ℝ) (hvK : vK.IsNontrivial)
  (w : AbsoluteValueExtension vK L)
local instance proposition98CompletionBaseAlgebra : Algebra K w.1.Completion :=
  AbsoluteValue.extensionCompletionAlgebra (K := K) w.1
local instance proposition98CompletionBaseSMul : SMul K w.1.Completion :=
  (AbsoluteValue.extensionCompletionAlgebra (K := K) w.1).toSMul
local instance proposition98CompletionAlgebra : Algebra vK.Completion w.1.Completion :=
  AbsoluteValue.completionAlgebra vK w.1 w.2
local instance proposition98LocalizationBaseAlgebra : Algebra K (localization vK w) :=
  ((algebraMap vK.Completion (localization vK w)).comp
    (algebraMap K vK.Completion)).toAlgebra
local instance proposition98LocalizationScalarTower :
    IsScalarTower K vK.Completion (localization vK w) :=
  IsScalarTower.of_algebraMap_eq' (by
    ext x
    rfl)
include hvK
omit hvK
omit [IsGalois K L] in
theorem decompositionField_decompositionField_nonarchimedean
    (hv : LubinTate.Valuations.NonarchimedeanAbsoluteValue vK) :
    LubinTate.Valuations.NonarchimedeanAbsoluteValue
      (AlgebraicNumberTheory.Valuations.absoluteValueRestrictIntermediateField w.1
        (absoluteValueDecompositionField K w.1))
HilbertRamification.decompositionField_completion_nonarchimedean

The norm absolute value on K_v is nonarchimedean whenever v is.

Source context 15 commands

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

noncomputable section
universe u v
namespace HilbertRamification
open AlgebraicNumberTheory.Valuations
variable {K : Type u} {L : Type v} [Field K] [Field L] [Algebra K L]
section LocalizationGalois
variable [IsGalois K L]
variable (vK : AbsoluteValue K ℝ) (hvK : vK.IsNontrivial)
  (w : AbsoluteValueExtension vK L)
local instance proposition98CompletionBaseAlgebra : Algebra K w.1.Completion :=
  AbsoluteValue.extensionCompletionAlgebra (K := K) w.1
local instance proposition98CompletionBaseSMul : SMul K w.1.Completion :=
  (AbsoluteValue.extensionCompletionAlgebra (K := K) w.1).toSMul
local instance proposition98CompletionAlgebra : Algebra vK.Completion w.1.Completion :=
  AbsoluteValue.completionAlgebra vK w.1 w.2
local instance proposition98LocalizationBaseAlgebra : Algebra K (localization vK w) :=
  ((algebraMap vK.Completion (localization vK w)).comp
    (algebraMap K vK.Completion)).toAlgebra
local instance proposition98LocalizationScalarTower :
    IsScalarTower K vK.Completion (localization vK w) :=
  IsScalarTower.of_algebraMap_eq' (by
    ext x
    rfl)
include hvK
omit hvK
theorem decompositionField_completion_nonarchimedean
    (hv : LubinTate.Valuations.NonarchimedeanAbsoluteValue vK) :
    LubinTate.Valuations.NonarchimedeanAbsoluteValue
      (AbsoluteValue.completionAbsoluteValue vK)
HilbertRamification.decompositionField_completionAbsoluteValue_range_eq

Completion does not enlarge the range of a nonarchimedean absolute value. This provides the value-group equality used in the decomposition-field extension comparison.

Source context 15 commands

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

noncomputable section
universe u v
namespace HilbertRamification
open AlgebraicNumberTheory.Valuations
variable {K : Type u} {L : Type v} [Field K] [Field L] [Algebra K L]
section LocalizationGalois
variable [IsGalois K L]
variable (vK : AbsoluteValue K ℝ) (hvK : vK.IsNontrivial)
  (w : AbsoluteValueExtension vK L)
local instance proposition98CompletionBaseAlgebra : Algebra K w.1.Completion :=
  AbsoluteValue.extensionCompletionAlgebra (K := K) w.1
local instance proposition98CompletionBaseSMul : SMul K w.1.Completion :=
  (AbsoluteValue.extensionCompletionAlgebra (K := K) w.1).toSMul
local instance proposition98CompletionAlgebra : Algebra vK.Completion w.1.Completion :=
  AbsoluteValue.completionAlgebra vK w.1 w.2
local instance proposition98LocalizationBaseAlgebra : Algebra K (localization vK w) :=
  ((algebraMap vK.Completion (localization vK w)).comp
    (algebraMap K vK.Completion)).toAlgebra
local instance proposition98LocalizationScalarTower :
    IsScalarTower K vK.Completion (localization vK w) :=
  IsScalarTower.of_algebraMap_eq' (by
    ext x
    rfl)
include hvK
omit hvK
theorem decompositionField_completionAbsoluteValue_range_eq
    (hv : LubinTate.Valuations.NonarchimedeanAbsoluteValue vK) :
    Set.range (AbsoluteValue.completionAbsoluteValue vK) = Set.range vK
HilbertRamification.decompositionField_decompositionField_valueRange_eq

The decomposition-field extension comparison, value-group form: w|Z_w and v have literally the same range in ℝ.

Source context 16 commands

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

noncomputable section
universe u v
namespace HilbertRamification
open AlgebraicNumberTheory.Valuations
variable {K : Type u} {L : Type v} [Field K] [Field L] [Algebra K L]
section LocalizationGalois
variable [IsGalois K L]
variable (vK : AbsoluteValue K ℝ) (hvK : vK.IsNontrivial)
  (w : AbsoluteValueExtension vK L)
local instance proposition98CompletionBaseAlgebra : Algebra K w.1.Completion :=
  AbsoluteValue.extensionCompletionAlgebra (K := K) w.1
local instance proposition98CompletionBaseSMul : SMul K w.1.Completion :=
  (AbsoluteValue.extensionCompletionAlgebra (K := K) w.1).toSMul
local instance proposition98CompletionAlgebra : Algebra vK.Completion w.1.Completion :=
  AbsoluteValue.completionAlgebra vK w.1 w.2
local instance proposition98LocalizationBaseAlgebra : Algebra K (localization vK w) :=
  ((algebraMap vK.Completion (localization vK w)).comp
    (algebraMap K vK.Completion)).toAlgebra
local instance proposition98LocalizationScalarTower :
    IsScalarTower K vK.Completion (localization vK w) :=
  IsScalarTower.of_algebraMap_eq' (by
    ext x
    rfl)
include hvK
omit hvK
include hvK
theorem decompositionField_decompositionField_valueRange_eq
    (hv : LubinTate.Valuations.NonarchimedeanAbsoluteValue vK) :
    Set.range
        (AlgebraicNumberTheory.Valuations.absoluteValueRestrictIntermediateField w.1
          (absoluteValueDecompositionField K w.1)) =
      Set.range vK
HilbertRamification.decompositionField_baseValuationSubring

The valuation subring of the nonarchimedean base absolute value.

Source context 17 commands

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

noncomputable section
universe u v
namespace HilbertRamification
open AlgebraicNumberTheory.Valuations
variable {K : Type u} {L : Type v} [Field K] [Field L] [Algebra K L]
section LocalizationGalois
variable [IsGalois K L]
variable (vK : AbsoluteValue K ℝ) (hvK : vK.IsNontrivial)
  (w : AbsoluteValueExtension vK L)
local instance proposition98CompletionBaseAlgebra : Algebra K w.1.Completion :=
  AbsoluteValue.extensionCompletionAlgebra (K := K) w.1
local instance proposition98CompletionBaseSMul : SMul K w.1.Completion :=
  (AbsoluteValue.extensionCompletionAlgebra (K := K) w.1).toSMul
local instance proposition98CompletionAlgebra : Algebra vK.Completion w.1.Completion :=
  AbsoluteValue.completionAlgebra vK w.1 w.2
local instance proposition98LocalizationBaseAlgebra : Algebra K (localization vK w) :=
  ((algebraMap vK.Completion (localization vK w)).comp
    (algebraMap K vK.Completion)).toAlgebra
local instance proposition98LocalizationScalarTower :
    IsScalarTower K vK.Completion (localization vK w) :=
  IsScalarTower.of_algebraMap_eq' (by
    ext x
    rfl)
include hvK
omit hvK
include hvK
omit hvK
abbrev decompositionField_baseValuationSubring
    (hv : LubinTate.Valuations.NonarchimedeanAbsoluteValue vK) :
    _root_.ValuationSubring K
HilbertRamification.decompositionField_decompositionFieldValuationSubring

The valuation subring of w|Z_w.

Source context 17 commands

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

noncomputable section
universe u v
namespace HilbertRamification
open AlgebraicNumberTheory.Valuations
variable {K : Type u} {L : Type v} [Field K] [Field L] [Algebra K L]
section LocalizationGalois
variable [IsGalois K L]
variable (vK : AbsoluteValue K ℝ) (hvK : vK.IsNontrivial)
  (w : AbsoluteValueExtension vK L)
local instance proposition98CompletionBaseAlgebra : Algebra K w.1.Completion :=
  AbsoluteValue.extensionCompletionAlgebra (K := K) w.1
local instance proposition98CompletionBaseSMul : SMul K w.1.Completion :=
  (AbsoluteValue.extensionCompletionAlgebra (K := K) w.1).toSMul
local instance proposition98CompletionAlgebra : Algebra vK.Completion w.1.Completion :=
  AbsoluteValue.completionAlgebra vK w.1 w.2
local instance proposition98LocalizationBaseAlgebra : Algebra K (localization vK w) :=
  ((algebraMap vK.Completion (localization vK w)).comp
    (algebraMap K vK.Completion)).toAlgebra
local instance proposition98LocalizationScalarTower :
    IsScalarTower K vK.Completion (localization vK w) :=
  IsScalarTower.of_algebraMap_eq' (by
    ext x
    rfl)
include hvK
omit hvK
include hvK
omit hvK
abbrev decompositionField_decompositionFieldValuationSubring
    (hv : LubinTate.Valuations.NonarchimedeanAbsoluteValue vK) :
    _root_.ValuationSubring (absoluteValueDecompositionField K w.1)
HilbertRamification.decompositionField_decompositionField_integerMap

The canonical local homomorphism between the two valuation subrings in the decomposition-field extension comparison.

Source context 17 commands

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

noncomputable section
universe u v
namespace HilbertRamification
open AlgebraicNumberTheory.Valuations
variable {K : Type u} {L : Type v} [Field K] [Field L] [Algebra K L]
section LocalizationGalois
variable [IsGalois K L]
variable (vK : AbsoluteValue K ℝ) (hvK : vK.IsNontrivial)
  (w : AbsoluteValueExtension vK L)
local instance proposition98CompletionBaseAlgebra : Algebra K w.1.Completion :=
  AbsoluteValue.extensionCompletionAlgebra (K := K) w.1
local instance proposition98CompletionBaseSMul : SMul K w.1.Completion :=
  (AbsoluteValue.extensionCompletionAlgebra (K := K) w.1).toSMul
local instance proposition98CompletionAlgebra : Algebra vK.Completion w.1.Completion :=
  AbsoluteValue.completionAlgebra vK w.1 w.2
local instance proposition98LocalizationBaseAlgebra : Algebra K (localization vK w) :=
  ((algebraMap vK.Completion (localization vK w)).comp
    (algebraMap K vK.Completion)).toAlgebra
local instance proposition98LocalizationScalarTower :
    IsScalarTower K vK.Completion (localization vK w) :=
  IsScalarTower.of_algebraMap_eq' (by
    ext x
    rfl)
include hvK
omit hvK
include hvK
omit hvK
def decompositionField_decompositionField_integerMap
    (hv : LubinTate.Valuations.NonarchimedeanAbsoluteValue vK) :
    decompositionField_baseValuationSubring vK hv →+*
      decompositionField_decompositionFieldValuationSubring vK w hv
HilbertRamification.decompositionField_decompositionField_integerMap_apply
Source context 18 commands

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

noncomputable section
universe u v
namespace HilbertRamification
open AlgebraicNumberTheory.Valuations
variable {K : Type u} {L : Type v} [Field K] [Field L] [Algebra K L]
section LocalizationGalois
variable [IsGalois K L]
variable (vK : AbsoluteValue K ℝ) (hvK : vK.IsNontrivial)
  (w : AbsoluteValueExtension vK L)
local instance proposition98CompletionBaseAlgebra : Algebra K w.1.Completion :=
  AbsoluteValue.extensionCompletionAlgebra (K := K) w.1
local instance proposition98CompletionBaseSMul : SMul K w.1.Completion :=
  (AbsoluteValue.extensionCompletionAlgebra (K := K) w.1).toSMul
local instance proposition98CompletionAlgebra : Algebra vK.Completion w.1.Completion :=
  AbsoluteValue.completionAlgebra vK w.1 w.2
local instance proposition98LocalizationBaseAlgebra : Algebra K (localization vK w) :=
  ((algebraMap vK.Completion (localization vK w)).comp
    (algebraMap K vK.Completion)).toAlgebra
local instance proposition98LocalizationScalarTower :
    IsScalarTower K vK.Completion (localization vK w) :=
  IsScalarTower.of_algebraMap_eq' (by
    ext x
    rfl)
include hvK
omit hvK
include hvK
omit hvK
omit [IsGalois K L] in
theorem decompositionField_decompositionField_integerMap_apply
    (hv : LubinTate.Valuations.NonarchimedeanAbsoluteValue vK)
    (x : decompositionField_baseValuationSubring vK hv) :
    ((decompositionField_decompositionField_integerMap vK w hv x :
        decompositionField_decompositionFieldValuationSubring vK w hv) :
      absoluteValueDecompositionField K w.1) =
      algebraMap K (absoluteValueDecompositionField K w.1) (x : K)
HilbertRamification.decompositionField_decompositionField_integerMap_isLocalHom

The valuation-ring map in the decomposition-field extension comparison is local.

Source context 17 commands

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

noncomputable section
universe u v
namespace HilbertRamification
open AlgebraicNumberTheory.Valuations
variable {K : Type u} {L : Type v} [Field K] [Field L] [Algebra K L]
section LocalizationGalois
variable [IsGalois K L]
variable (vK : AbsoluteValue K ℝ) (hvK : vK.IsNontrivial)
  (w : AbsoluteValueExtension vK L)
local instance proposition98CompletionBaseAlgebra : Algebra K w.1.Completion :=
  AbsoluteValue.extensionCompletionAlgebra (K := K) w.1
local instance proposition98CompletionBaseSMul : SMul K w.1.Completion :=
  (AbsoluteValue.extensionCompletionAlgebra (K := K) w.1).toSMul
local instance proposition98CompletionAlgebra : Algebra vK.Completion w.1.Completion :=
  AbsoluteValue.completionAlgebra vK w.1 w.2
local instance proposition98LocalizationBaseAlgebra : Algebra K (localization vK w) :=
  ((algebraMap vK.Completion (localization vK w)).comp
    (algebraMap K vK.Completion)).toAlgebra
local instance proposition98LocalizationScalarTower :
    IsScalarTower K vK.Completion (localization vK w) :=
  IsScalarTower.of_algebraMap_eq' (by
    ext x
    rfl)
include hvK
omit hvK
include hvK
omit hvK
instance decompositionField_decompositionField_integerMap_isLocalHom
    (hv : LubinTate.Valuations.NonarchimedeanAbsoluteValue vK) :
    IsLocalHom (decompositionField_decompositionField_integerMap vK w hv) where
  map_nonunit x hx := by
    rw [← IsLocalRing.notMem_maximalIdeal] at hx ⊢
    intro hxmax
    apply hx
    have hxabs : vK (x : K) < 1 :=
      (absoluteValueValuationSubring_mem_maximalIdeal_iff_abs_lt_one
        vK hv x).mp hxmax
    rw [absoluteValueValuationSubring_mem_maximalIdeal_iff_abs_lt_one]
    rw [decompositionField_decompositionField_integerMap_apply]
    change w.1 (algebraMap
      (absoluteValueDecompositionField K w.1) L
      (algebraMap K (absoluteValueDecompositionField K w.1) (x : K))) < 1
    rw [← IsScalarTower.algebraMap_apply K
      (absoluteValueDecompositionField K w.1) L, w.2]
    exact hxabs
HilbertRamification.decompositionField_decompositionField_residueMap

The induced canonical map of actual residue fields.

Source context 17 commands

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

noncomputable section
universe u v
namespace HilbertRamification
open AlgebraicNumberTheory.Valuations
variable {K : Type u} {L : Type v} [Field K] [Field L] [Algebra K L]
section LocalizationGalois
variable [IsGalois K L]
variable (vK : AbsoluteValue K ℝ) (hvK : vK.IsNontrivial)
  (w : AbsoluteValueExtension vK L)
local instance proposition98CompletionBaseAlgebra : Algebra K w.1.Completion :=
  AbsoluteValue.extensionCompletionAlgebra (K := K) w.1
local instance proposition98CompletionBaseSMul : SMul K w.1.Completion :=
  (AbsoluteValue.extensionCompletionAlgebra (K := K) w.1).toSMul
local instance proposition98CompletionAlgebra : Algebra vK.Completion w.1.Completion :=
  AbsoluteValue.completionAlgebra vK w.1 w.2
local instance proposition98LocalizationBaseAlgebra : Algebra K (localization vK w) :=
  ((algebraMap vK.Completion (localization vK w)).comp
    (algebraMap K vK.Completion)).toAlgebra
local instance proposition98LocalizationScalarTower :
    IsScalarTower K vK.Completion (localization vK w) :=
  IsScalarTower.of_algebraMap_eq' (by
    ext x
    rfl)
include hvK
omit hvK
include hvK
omit hvK
def decompositionField_decompositionField_residueMap
    (hv : LubinTate.Valuations.NonarchimedeanAbsoluteValue vK) :
    IsLocalRing.ResidueField (decompositionField_baseValuationSubring vK hv) →+*
      IsLocalRing.ResidueField
        (decompositionField_decompositionFieldValuationSubring vK w hv)
HilbertRamification.decompositionField_decompositionField_residueMap_surjective

The canonical residue-field map in the decomposition-field extension comparison is surjective. The proof chooses a representative in K_v, then approximates it modulo the maximal ideal by an element of K.

Source context 18 commands

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

noncomputable section
universe u v
namespace HilbertRamification
open AlgebraicNumberTheory.Valuations
variable {K : Type u} {L : Type v} [Field K] [Field L] [Algebra K L]
section LocalizationGalois
variable [IsGalois K L]
variable (vK : AbsoluteValue K ℝ) (hvK : vK.IsNontrivial)
  (w : AbsoluteValueExtension vK L)
local instance proposition98CompletionBaseAlgebra : Algebra K w.1.Completion :=
  AbsoluteValue.extensionCompletionAlgebra (K := K) w.1
local instance proposition98CompletionBaseSMul : SMul K w.1.Completion :=
  (AbsoluteValue.extensionCompletionAlgebra (K := K) w.1).toSMul
local instance proposition98CompletionAlgebra : Algebra vK.Completion w.1.Completion :=
  AbsoluteValue.completionAlgebra vK w.1 w.2
local instance proposition98LocalizationBaseAlgebra : Algebra K (localization vK w) :=
  ((algebraMap vK.Completion (localization vK w)).comp
    (algebraMap K vK.Completion)).toAlgebra
local instance proposition98LocalizationScalarTower :
    IsScalarTower K vK.Completion (localization vK w) :=
  IsScalarTower.of_algebraMap_eq' (by
    ext x
    rfl)
include hvK
omit hvK
include hvK
omit hvK
include hvK
theorem decompositionField_decompositionField_residueMap_surjective
    (hv : LubinTate.Valuations.NonarchimedeanAbsoluteValue vK) :
    Function.Surjective
      (decompositionField_decompositionField_residueMap vK w hv)
HilbertRamification.decompositionField_decompositionField_residueFieldEquiv

The decomposition-field extension comparison, residue-field form: the canonical residue map is an isomorphism of the actual residue fields.

Source context 18 commands

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

noncomputable section
universe u v
namespace HilbertRamification
open AlgebraicNumberTheory.Valuations
variable {K : Type u} {L : Type v} [Field K] [Field L] [Algebra K L]
section LocalizationGalois
variable [IsGalois K L]
variable (vK : AbsoluteValue K ℝ) (hvK : vK.IsNontrivial)
  (w : AbsoluteValueExtension vK L)
local instance proposition98CompletionBaseAlgebra : Algebra K w.1.Completion :=
  AbsoluteValue.extensionCompletionAlgebra (K := K) w.1
local instance proposition98CompletionBaseSMul : SMul K w.1.Completion :=
  (AbsoluteValue.extensionCompletionAlgebra (K := K) w.1).toSMul
local instance proposition98CompletionAlgebra : Algebra vK.Completion w.1.Completion :=
  AbsoluteValue.completionAlgebra vK w.1 w.2
local instance proposition98LocalizationBaseAlgebra : Algebra K (localization vK w) :=
  ((algebraMap vK.Completion (localization vK w)).comp
    (algebraMap K vK.Completion)).toAlgebra
local instance proposition98LocalizationScalarTower :
    IsScalarTower K vK.Completion (localization vK w) :=
  IsScalarTower.of_algebraMap_eq' (by
    ext x
    rfl)
include hvK
omit hvK
include hvK
omit hvK
include hvK
def decompositionField_decompositionField_residueFieldEquiv
    (hv : LubinTate.Valuations.NonarchimedeanAbsoluteValue vK) :
    IsLocalRing.ResidueField (decompositionField_baseValuationSubring vK hv) ≃+*
      IsLocalRing.ResidueField
        (decompositionField_decompositionFieldValuationSubring vK w hv)
HilbertRamification.decompositionField_decompositionField_residueFieldEquiv_apply
Source context 18 commands

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

noncomputable section
universe u v
namespace HilbertRamification
open AlgebraicNumberTheory.Valuations
variable {K : Type u} {L : Type v} [Field K] [Field L] [Algebra K L]
section LocalizationGalois
variable [IsGalois K L]
variable (vK : AbsoluteValue K ℝ) (hvK : vK.IsNontrivial)
  (w : AbsoluteValueExtension vK L)
local instance proposition98CompletionBaseAlgebra : Algebra K w.1.Completion :=
  AbsoluteValue.extensionCompletionAlgebra (K := K) w.1
local instance proposition98CompletionBaseSMul : SMul K w.1.Completion :=
  (AbsoluteValue.extensionCompletionAlgebra (K := K) w.1).toSMul
local instance proposition98CompletionAlgebra : Algebra vK.Completion w.1.Completion :=
  AbsoluteValue.completionAlgebra vK w.1 w.2
local instance proposition98LocalizationBaseAlgebra : Algebra K (localization vK w) :=
  ((algebraMap vK.Completion (localization vK w)).comp
    (algebraMap K vK.Completion)).toAlgebra
local instance proposition98LocalizationScalarTower :
    IsScalarTower K vK.Completion (localization vK w) :=
  IsScalarTower.of_algebraMap_eq' (by
    ext x
    rfl)
include hvK
omit hvK
include hvK
omit hvK
include hvK
theorem decompositionField_decompositionField_residueFieldEquiv_apply
    (hv : LubinTate.Valuations.NonarchimedeanAbsoluteValue vK)
    (x : IsLocalRing.ResidueField
      (decompositionField_baseValuationSubring vK hv)) :
    decompositionField_decompositionField_residueFieldEquiv vK hvK w hv x =
      decompositionField_decompositionField_residueMap vK w hv x