Module

CompletedChangedStandardCompositum.lean

Nyll.ClassFieldTheory.LubinTate.Padic.CompletedChangedStandardCompositum
24 declarations indexed from sourceView source ↗

The finite standard/changed compositum in the completed p-adic level

The completed level contains two finite abelian extensions of ℚ_[p]:

  • the image of the ordinary standard multiplicative Lubin--Tate level;
  • the fixed field of the inverse-unit completed Frobenius lift, identified

with the changed-uniformizer level.

Their compositum is therefore a genuine finite abelian extension. The inverse of the Frobenius lift preserves this compositum, fixes the changed factor, and acts on the standard factor by the direct unit parameter. This is the finite automorphism which the changed-uniformizer norm calculation will identify with the actual local Artin symbol.

Declarations

LubinTate.padicCompletedStandardLevelField

The copy of the ordinary standard multiplicative level inside the completed level.

Source context 4 commands

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

noncomputable section
namespace LubinTate
open LocalFieldTheory.DiscreteValuationField
open LocalFieldTheory.DiscreteValuationField.Examples.Qp
def padicCompletedStandardLevelField
    (p : ℕ) [Fact p.Prime] (n : ℕ) :
    IntermediateField ℚ_[p] (padicCompletedLevelField p n)
LubinTate.padicStandardLevelEquivCompletedStandardLevelField

The ordinary standard level is equivalent to its image in the completed level.

Source context 4 commands

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

noncomputable section
namespace LubinTate
open LocalFieldTheory.DiscreteValuationField
open LocalFieldTheory.DiscreteValuationField.Examples.Qp
def padicStandardLevelEquivCompletedStandardLevelField
    (p : ℕ) [Fact p.Prime] (n : ℕ) :
    standardLubinTateLevelField
        (padicMultiplicativeLubinTateSeries_isUniformizer p) n
      ≃ₐ[ℚ_[p]]
        padicCompletedStandardLevelField p n
LubinTate.padicCompletedStandardLevelField_finiteDimensional
Source context 4 commands

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

noncomputable section
namespace LubinTate
open LocalFieldTheory.DiscreteValuationField
open LocalFieldTheory.DiscreteValuationField.Examples.Qp
instance
    padicCompletedStandardLevelField_finiteDimensional
    (p : ℕ) [Fact p.Prime] (n : ℕ) :
    FiniteDimensional ℚ_[p]
      (padicCompletedStandardLevelField p n)
LubinTate.padicCompletedStandardLevelField_isAbelianGalois
Source context 4 commands

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

noncomputable section
namespace LubinTate
open LocalFieldTheory.DiscreteValuationField
open LocalFieldTheory.DiscreteValuationField.Examples.Qp
instance
    padicCompletedStandardLevelField_isAbelianGalois
    (p : ℕ) [Fact p.Prime] (n : ℕ) :
    IsAbelianGalois ℚ_[p]
      (padicCompletedStandardLevelField p n)
LubinTate.padicCompletedChangedUniformizerFixedField_finiteDimensional
Source context 4 commands

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

noncomputable section
namespace LubinTate
open LocalFieldTheory.DiscreteValuationField
open LocalFieldTheory.DiscreteValuationField.Examples.Qp
instance
    padicCompletedChangedUniformizerFixedField_finiteDimensional
    (p : ℕ) [Fact p.Prime]
    (u : (padicLocalField p).valuationSubringˣ) (n : ℕ) :
    FiniteDimensional ℚ_[p]
      (padicCompletedChangedUniformizerFixedField p u n)
LubinTate.padicCompletedChangedUniformizerFixedField_isAbelianGalois
Source context 4 commands

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

noncomputable section
namespace LubinTate
open LocalFieldTheory.DiscreteValuationField
open LocalFieldTheory.DiscreteValuationField.Examples.Qp
instance
    padicCompletedChangedUniformizerFixedField_isAbelianGalois
    (p : ℕ) [Fact p.Prime]
    (u : (padicLocalField p).valuationSubringˣ) (n : ℕ) :
    IsAbelianGalois ℚ_[p]
      (padicCompletedChangedUniformizerFixedField p u n)
LubinTate.padicCompletedStandardChangedCompositum

The finite compositum of the standard level and the actual changed-uniformizer fixed field inside the completed level.

Source context 4 commands

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

noncomputable section
namespace LubinTate
open LocalFieldTheory.DiscreteValuationField
open LocalFieldTheory.DiscreteValuationField.Examples.Qp
def padicCompletedStandardChangedCompositum
    (p : ℕ) [Fact p.Prime]
    (u : (padicLocalField p).valuationSubringˣ) (n : ℕ) :
    IntermediateField ℚ_[p] (padicCompletedLevelField p n)
LubinTate.padicCompletedStandardChangedCompositum_finiteDimensional
Source context 4 commands

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

noncomputable section
namespace LubinTate
open LocalFieldTheory.DiscreteValuationField
open LocalFieldTheory.DiscreteValuationField.Examples.Qp
instance
    padicCompletedStandardChangedCompositum_finiteDimensional
    (p : ℕ) [Fact p.Prime]
    (u : (padicLocalField p).valuationSubringˣ) (n : ℕ) :
    FiniteDimensional ℚ_[p]
      (padicCompletedStandardChangedCompositum p u n)
LubinTate.padicCompletedStandardChangedCompositum_isAbelianGalois
Source context 4 commands

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

noncomputable section
namespace LubinTate
open LocalFieldTheory.DiscreteValuationField
open LocalFieldTheory.DiscreteValuationField.Examples.Qp
instance
    padicCompletedStandardChangedCompositum_isAbelianGalois
    (p : ℕ) [Fact p.Prime]
    (u : (padicLocalField p).valuationSubringˣ) (n : ℕ) :
    IsAbelianGalois ℚ_[p]
      (padicCompletedStandardChangedCompositum p u n)
LubinTate.padicCompletedStandardChangedCompositum_changedFieldAlgebra
Source context 4 commands

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

noncomputable section
namespace LubinTate
open LocalFieldTheory.DiscreteValuationField
open LocalFieldTheory.DiscreteValuationField.Examples.Qp
instance
    padicCompletedStandardChangedCompositum_changedFieldAlgebra
    (p : ℕ) [Fact p.Prime]
    (u : (padicLocalField p).valuationSubringˣ) (n : ℕ) :
    Algebra (padicCompletedChangedUniformizerFixedField p u n)
      (padicCompletedStandardChangedCompositum p u n)
LubinTate.padicCompletedStandardChangedCompositum_changedFieldScalarTower
Source context 4 commands

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

noncomputable section
namespace LubinTate
open LocalFieldTheory.DiscreteValuationField
open LocalFieldTheory.DiscreteValuationField.Examples.Qp
instance padicCompletedStandardChangedCompositum_changedFieldScalarTower
    (p : ℕ) [Fact p.Prime]
    (u : (padicLocalField p).valuationSubringˣ) (n : ℕ) :
    IsScalarTower ℚ_[p]
      (padicCompletedChangedUniformizerFixedField p u n)
      (padicCompletedStandardChangedCompositum p u n)
LubinTate.padicCompletedStandardChangedCompositum_relative_isAbelianGalois

The standard/changed compositum is also abelian Galois over its changed-uniformizer factor. Relative automorphisms embed faithfully into the already commutative Galois group over ℚ_p.

Source context 4 commands

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

noncomputable section
namespace LubinTate
open LocalFieldTheory.DiscreteValuationField
open LocalFieldTheory.DiscreteValuationField.Examples.Qp
instance
    padicCompletedStandardChangedCompositum_relative_isAbelianGalois
    (p : ℕ) [Fact p.Prime]
    (u : (padicLocalField p).valuationSubringˣ) (n : ℕ) :
    IsAbelianGalois
      (padicCompletedChangedUniformizerFixedField p u n)
      (padicCompletedStandardChangedCompositum p u n)
LubinTate.padicStandardLevelToCompletedChangedCompositum

The standard finite level embedded into the finite standard/changed compositum.

Source context 4 commands

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

noncomputable section
namespace LubinTate
open LocalFieldTheory.DiscreteValuationField
open LocalFieldTheory.DiscreteValuationField.Examples.Qp
def padicStandardLevelToCompletedChangedCompositum
    (p : ℕ) [Fact p.Prime]
    (u : (padicLocalField p).valuationSubringˣ) (n : ℕ) :
    standardLubinTateLevelField
        (padicMultiplicativeLubinTateSeries_isUniformizer p) n
      →ₐ[ℚ_[p]]
        padicCompletedStandardChangedCompositum p u n
LubinTate.padicCompletedChangedFixedFieldToStandardChangedCompositum

The changed fixed field included into the finite standard/changed compositum.

Source context 4 commands

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

noncomputable section
namespace LubinTate
open LocalFieldTheory.DiscreteValuationField
open LocalFieldTheory.DiscreteValuationField.Examples.Qp
def
    padicCompletedChangedFixedFieldToStandardChangedCompositum
    (p : ℕ) [Fact p.Prime]
    (u : (padicLocalField p).valuationSubringˣ) (n : ℕ) :
    padicCompletedChangedUniformizerFixedField p u n
      →ₐ[ℚ_[p]]
        padicCompletedStandardChangedCompositum p u n
LubinTate.padicCompletedChangedUniformizerFrobenius_symm_map_standard_le

The inverse-unit Frobenius inverse carries the standard completed copy to itself.

Source context 4 commands

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

noncomputable section
namespace LubinTate
open LocalFieldTheory.DiscreteValuationField
open LocalFieldTheory.DiscreteValuationField.Examples.Qp
theorem
    padicCompletedChangedUniformizerFrobenius_symm_map_standard_le
    (p : ℕ) [Fact p.Prime]
    (u : (padicLocalField p).valuationSubringˣ) (n : ℕ) :
    (padicCompletedStandardLevelField p n).map
        (padicCompletedChangedUniformizerFrobeniusAlgEquiv
          p u n).symm.toAlgHom ≤
      padicCompletedStandardLevelField p n
LubinTate.padicCompletedChangedUniformizerFrobenius_symm_fixed

Every element of the changed fixed field is fixed by the inverse of its defining Frobenius lift.

Source context 4 commands

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

noncomputable section
namespace LubinTate
open LocalFieldTheory.DiscreteValuationField
open LocalFieldTheory.DiscreteValuationField.Examples.Qp
theorem
    padicCompletedChangedUniformizerFrobenius_symm_fixed
    (p : ℕ) [Fact p.Prime]
    (u : (padicLocalField p).valuationSubringˣ) (n : ℕ)
    (x : padicCompletedChangedUniformizerFixedField p u n) :
    (padicCompletedChangedUniformizerFrobeniusAlgEquiv p u n).symm
      (x : padicCompletedLevelField p n) =
        x
LubinTate.padicCompletedChangedUniformizerFrobenius_symm_map_fixedField_le

The inverse defining Frobenius carries the changed fixed field to itself.

Source context 4 commands

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

noncomputable section
namespace LubinTate
open LocalFieldTheory.DiscreteValuationField
open LocalFieldTheory.DiscreteValuationField.Examples.Qp
theorem
    padicCompletedChangedUniformizerFrobenius_symm_map_fixedField_le
    (p : ℕ) [Fact p.Prime]
    (u : (padicLocalField p).valuationSubringˣ) (n : ℕ) :
    (padicCompletedChangedUniformizerFixedField p u n).map
        (padicCompletedChangedUniformizerFrobeniusAlgEquiv
          p u n).symm.toAlgHom ≤
      padicCompletedChangedUniformizerFixedField p u n
LubinTate.padicCompletedChangedUniformizerFrobenius_symm_map_compositum_le

The inverse defining Frobenius preserves the finite standard/changed compositum.

Source context 4 commands

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

noncomputable section
namespace LubinTate
open LocalFieldTheory.DiscreteValuationField
open LocalFieldTheory.DiscreteValuationField.Examples.Qp
theorem
    padicCompletedChangedUniformizerFrobenius_symm_map_compositum_le
    (p : ℕ) [Fact p.Prime]
    (u : (padicLocalField p).valuationSubringˣ) (n : ℕ) :
    (padicCompletedStandardChangedCompositum p u n).map
        (padicCompletedChangedUniformizerFrobeniusAlgEquiv
          p u n).symm.toAlgHom ≤
      padicCompletedStandardChangedCompositum p u n
LubinTate.padicCompletedChangedUniformizerArtinCandidateAlgHom

The inverse defining Frobenius restricted to the genuine finite standard/changed compositum.

Source context 4 commands

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

noncomputable section
namespace LubinTate
open LocalFieldTheory.DiscreteValuationField
open LocalFieldTheory.DiscreteValuationField.Examples.Qp
def padicCompletedChangedUniformizerArtinCandidateAlgHom
    (p : ℕ) [Fact p.Prime]
    (u : (padicLocalField p).valuationSubringˣ) (n : ℕ) :
    padicCompletedStandardChangedCompositum p u n
      →ₐ[ℚ_[p]]
        padicCompletedStandardChangedCompositum p u n
LubinTate.padicCompletedChangedUniformizerArtinCandidate

The finite Artin candidate is an automorphism.

Source context 4 commands

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

noncomputable section
namespace LubinTate
open LocalFieldTheory.DiscreteValuationField
open LocalFieldTheory.DiscreteValuationField.Examples.Qp
def padicCompletedChangedUniformizerArtinCandidate
    (p : ℕ) [Fact p.Prime]
    (u : (padicLocalField p).valuationSubringˣ) (n : ℕ) :
    padicCompletedStandardChangedCompositum p u n
      ≃ₐ[ℚ_[p]]
        padicCompletedStandardChangedCompositum p u n
LubinTate.padicCompletedChangedUniformizerArtinCandidate_standardLevel

On the standard factor, the finite Artin candidate is the direct unit-parameter automorphism.

Source context 4 commands

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

noncomputable section
namespace LubinTate
open LocalFieldTheory.DiscreteValuationField
open LocalFieldTheory.DiscreteValuationField.Examples.Qp
theorem
    padicCompletedChangedUniformizerArtinCandidate_standardLevel
    (p : ℕ) [Fact p.Prime]
    (u : (padicLocalField p).valuationSubringˣ) (n : ℕ)
    (x :
      standardLubinTateLevelField
        (padicMultiplicativeLubinTateSeries_isUniformizer p) n) :
    padicCompletedChangedUniformizerArtinCandidate p u n
        (padicStandardLevelToCompletedChangedCompositum p u n x) =
      padicStandardLevelToCompletedChangedCompositum p u n
        (standardLubinTateUnitParameterAlgEquiv
          (padicLocalField p)
          (padicMultiplicativeLubinTateSeries_isUniformizer p) n
          (standardLubinTateUnitParameterClass
            (padicLocalField p) n u) x)
LubinTate.padicCompletedChangedUniformizerArtinCandidate_fixedField

On the changed factor, the finite Artin candidate is the identity.

Source context 4 commands

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

noncomputable section
namespace LubinTate
open LocalFieldTheory.DiscreteValuationField
open LocalFieldTheory.DiscreteValuationField.Examples.Qp
theorem
    padicCompletedChangedUniformizerArtinCandidate_fixedField
    (p : ℕ) [Fact p.Prime]
    (u : (padicLocalField p).valuationSubringˣ) (n : ℕ)
    (x : padicCompletedChangedUniformizerFixedField p u n) :
    padicCompletedChangedUniformizerArtinCandidate p u n
        (padicCompletedChangedFixedFieldToStandardChangedCompositum
          p u n x) =
      padicCompletedChangedFixedFieldToStandardChangedCompositum
        p u n x
LubinTate.padicCompletedChangedUniformizerRelativeArtinCandidate

The finite Artin candidate as an automorphism over the changed fixed field that it fixes pointwise.

Source context 4 commands

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

noncomputable section
namespace LubinTate
open LocalFieldTheory.DiscreteValuationField
open LocalFieldTheory.DiscreteValuationField.Examples.Qp
def
    padicCompletedChangedUniformizerRelativeArtinCandidate
    (p : ℕ) [Fact p.Prime]
    (u : (padicLocalField p).valuationSubringˣ) (n : ℕ) :
    padicCompletedStandardChangedCompositum p u n
      ≃ₐ[padicCompletedChangedUniformizerFixedField p u n]
        padicCompletedStandardChangedCompositum p u n where
  __ := (padicCompletedChangedUniformizerArtinCandidate p u n).toRingEquiv
  commutes' x :=
    padicCompletedChangedUniformizerArtinCandidate_fixedField
      p u n x
LubinTate.padicCompletedChangedUniformizerRelativeArtinCandidate_apply

Forgetting the changed-field scalar structure recovers the original finite candidate.

Source context 4 commands

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

noncomputable section
namespace LubinTate
open LocalFieldTheory.DiscreteValuationField
open LocalFieldTheory.DiscreteValuationField.Examples.Qp
theorem padicCompletedChangedUniformizerRelativeArtinCandidate_apply
    (p : ℕ) [Fact p.Prime]
    (u : (padicLocalField p).valuationSubringˣ) (n : ℕ)
    (x : padicCompletedStandardChangedCompositum p u n) :
    padicCompletedChangedUniformizerRelativeArtinCandidate p u n x =
      padicCompletedChangedUniformizerArtinCandidate p u n x