Module

LevelAlgebra.lean

Nyll.ClassFieldTheory.LubinTate.EqualCharacteristic.NormSubgroup.LevelAlgebra
4 declarations indexed from sourceView source ↗

LubinTate the explicit norm-subgroup computation: canonical algebra and norm subgroup at a

finite level

This light leaf names the canonical base algebra and its norm subgroup once, so the later inclusion and index arguments do not repeat expensive fallback typeclass searches.

Declarations

LubinTate.EqualCharacteristic.equalCharacteristicLaurentSeriesField
Source context 6 commands

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

noncomputable section
open scoped LaurentSeries
namespace LubinTate
namespace EqualCharacteristic
open LocalFieldTheory.DiscreteValuationField
variable {K : Type} [Field K]
instance equalCharacteristicLaurentSeriesField
    (F : LocalField K) : Field F.residueField⸨X⸩
LubinTate.EqualCharacteristic.equalCharacteristicLaurentSeriesMonoid
Source context 7 commands

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

noncomputable section
open scoped LaurentSeries
namespace LubinTate
namespace EqualCharacteristic
open LocalFieldTheory.DiscreteValuationField
variable {K : Type} [Field K]
noncomputable local instance equalCharacteristicLaurentSeriesField
    (F : LocalField K) : Field F.residueField⸨X⸩ :=
  @HahnSeries.instField ℤ F.residueField Int.instAddCommGroup
    Int.instLinearOrder Int.instIsOrderedAddMonoid inferInstance
instance equalCharacteristicLaurentSeriesMonoid
    (F : LocalField K) : Monoid F.residueField⸨X⸩
LubinTate.EqualCharacteristic.equalCharacteristicLubinTateLevelAlgebra

The canonical base algebra on the explicit Lubin--Tate level field.

Source context 9 commands

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

noncomputable section
open scoped LaurentSeries
namespace LubinTate
namespace EqualCharacteristic
open LocalFieldTheory.DiscreteValuationField
variable {K : Type} [Field K]
noncomputable local instance equalCharacteristicLaurentSeriesField
    (F : LocalField K) : Field F.residueField⸨X⸩ :=
  @HahnSeries.instField ℤ F.residueField Int.instAddCommGroup
    Int.instLinearOrder Int.instIsOrderedAddMonoid inferInstance
noncomputable local instance equalCharacteristicLaurentSeriesMonoid
    (F : LocalField K) : Monoid F.residueField⸨X⸩ :=
  @CommMonoid.toMonoid F.residueField⸨X⸩
    (@CommRing.toCommMonoid F.residueField⸨X⸩
      (@Field.toCommRing F.residueField⸨X⸩
        (equalCharacteristicLaurentSeriesField F)))
attribute [local instance]
  equalCharacteristicLubinTateLevelFieldAlgebra
  equalCharacteristicLubinTateLevelFieldSMul
  equalCharacteristicLubinTateLevelFieldModule
def equalCharacteristicLubinTateLevelAlgebra
    (F : LocalField K) [CharP K F.residueCharacteristic] (n : ℕ) :
    Algebra F.residueField⸨X⸩
      (equalCharacteristicLubinTateLevelField F n)
LubinTate.EqualCharacteristic.equalCharacteristicLubinTateNormSubgroup

The norm subgroup of the explicit Lubin--Tate level, with the canonical base algebra fixed once for downstream statements.

Source context 9 commands

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

noncomputable section
open scoped LaurentSeries
namespace LubinTate
namespace EqualCharacteristic
open LocalFieldTheory.DiscreteValuationField
variable {K : Type} [Field K]
noncomputable local instance equalCharacteristicLaurentSeriesField
    (F : LocalField K) : Field F.residueField⸨X⸩ :=
  @HahnSeries.instField ℤ F.residueField Int.instAddCommGroup
    Int.instLinearOrder Int.instIsOrderedAddMonoid inferInstance
noncomputable local instance equalCharacteristicLaurentSeriesMonoid
    (F : LocalField K) : Monoid F.residueField⸨X⸩ :=
  @CommMonoid.toMonoid F.residueField⸨X⸩
    (@CommRing.toCommMonoid F.residueField⸨X⸩
      (@Field.toCommRing F.residueField⸨X⸩
        (equalCharacteristicLaurentSeriesField F)))
attribute [local instance]
  equalCharacteristicLubinTateLevelFieldAlgebra
  equalCharacteristicLubinTateLevelFieldSMul
  equalCharacteristicLubinTateLevelFieldModule
def equalCharacteristicLubinTateNormSubgroup
    (F : LocalField K) [CharP K F.residueCharacteristic] (n : ℕ) :
    Subgroup F.residueField⸨X⸩ˣ