Module

TeichmullerLift.lean

Nyll.ValuedFieldTheory.LocalField.DiscreteValuationField.PrincipalUnits.TeichmullerLift
14 declarations indexed from sourceView source ↗

Teichmuller lifts

Constructs multiplicative Teichmuller representatives, and in equal characteristic the coefficient-field section of the residue map.

Declarations

LocalFieldTheory.DiscreteValuationField.CompleteDVF.higherPrincipalUnitGroup.residueTeichmullerLift

The Teichmuller representative lift from the finite residue field to the valuation ring: 0 lifts to 0, and nonzero residue classes lift through the root-of-unity splitting of κˣ.

Source context 11 commands

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

namespace LocalFieldTheory
open ValuationTheory
open ValuationTheory.DiscreteValuationField.ResidueField
noncomputable section
open scoped BigOperators
universe u v
namespace DiscreteValuationField
namespace CompleteDVF
variable {K : Type u} [Field K]
namespace higherPrincipalUnitGroup
variable (F : ValuationTheory.DiscreteValuationField.CompleteDVF.{u, v} K)
def residueTeichmullerLift [Finite F.residueField] :
    F.residueField → F.valuationSubring
LocalFieldTheory.DiscreteValuationField.CompleteDVF.higherPrincipalUnitGroup.residueTeichmullerLift_zero

Establishes the identity higherPrincipalUnitGroup.residueTeichmullerLift F 0 = 0.

Source context 11 commands

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

namespace LocalFieldTheory
open ValuationTheory
open ValuationTheory.DiscreteValuationField.ResidueField
noncomputable section
open scoped BigOperators
universe u v
namespace DiscreteValuationField
namespace CompleteDVF
variable {K : Type u} [Field K]
namespace higherPrincipalUnitGroup
variable (F : ValuationTheory.DiscreteValuationField.CompleteDVF.{u, v} K)
theorem residueTeichmullerLift_zero [Finite F.residueField] :
    higherPrincipalUnitGroup.residueTeichmullerLift F 0 = 0
LocalFieldTheory.DiscreteValuationField.CompleteDVF.higherPrincipalUnitGroup.residueTeichmullerLift_one

Establishes the identity higherPrincipalUnitGroup.residueTeichmullerLift F 1 = 1.

Source context 11 commands

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

namespace LocalFieldTheory
open ValuationTheory
open ValuationTheory.DiscreteValuationField.ResidueField
noncomputable section
open scoped BigOperators
universe u v
namespace DiscreteValuationField
namespace CompleteDVF
variable {K : Type u} [Field K]
namespace higherPrincipalUnitGroup
variable (F : ValuationTheory.DiscreteValuationField.CompleteDVF.{u, v} K)
theorem residueTeichmullerLift_one [Finite F.residueField] :
    higherPrincipalUnitGroup.residueTeichmullerLift F 1 = 1
LocalFieldTheory.DiscreteValuationField.CompleteDVF.higherPrincipalUnitGroup.residueMap_residueTeichmullerLift

The Teichmuller lift reduces to the residue class it lifts.

Source context 11 commands

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

namespace LocalFieldTheory
open ValuationTheory
open ValuationTheory.DiscreteValuationField.ResidueField
noncomputable section
open scoped BigOperators
universe u v
namespace DiscreteValuationField
namespace CompleteDVF
variable {K : Type u} [Field K]
namespace higherPrincipalUnitGroup
variable (F : ValuationTheory.DiscreteValuationField.CompleteDVF.{u, v} K)
theorem residueMap_residueTeichmullerLift [Finite F.residueField]
    (y : F.residueField) :
    F.residueMap (higherPrincipalUnitGroup.residueTeichmullerLift F y) = y
LocalFieldTheory.DiscreteValuationField.CompleteDVF.higherPrincipalUnitGroup.residueTeichmullerLift_mul

The Teichmuller lift is multiplicative.

Source context 11 commands

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

namespace LocalFieldTheory
open ValuationTheory
open ValuationTheory.DiscreteValuationField.ResidueField
noncomputable section
open scoped BigOperators
universe u v
namespace DiscreteValuationField
namespace CompleteDVF
variable {K : Type u} [Field K]
namespace higherPrincipalUnitGroup
variable (F : ValuationTheory.DiscreteValuationField.CompleteDVF.{u, v} K)
theorem residueTeichmullerLift_mul [Finite F.residueField]
    (x y : F.residueField) :
    higherPrincipalUnitGroup.residueTeichmullerLift F (x * y) =
      higherPrincipalUnitGroup.residueTeichmullerLift F x *
        higherPrincipalUnitGroup.residueTeichmullerLift F y
LocalFieldTheory.DiscreteValuationField.CompleteDVF.higherPrincipalUnitGroup.residueTeichmullerLift_pow_card

Every Teichmuller representative is a root of T^q - T, where q = #κ.

Source context 11 commands

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

namespace LocalFieldTheory
open ValuationTheory
open ValuationTheory.DiscreteValuationField.ResidueField
noncomputable section
open scoped BigOperators
universe u v
namespace DiscreteValuationField
namespace CompleteDVF
variable {K : Type u} [Field K]
namespace higherPrincipalUnitGroup
variable (F : ValuationTheory.DiscreteValuationField.CompleteDVF.{u, v} K)
theorem residueTeichmullerLift_pow_card [Finite F.residueField]
    (y : F.residueField) :
    higherPrincipalUnitGroup.residueTeichmullerLift F y ^
        Nat.card F.residueField =
      higherPrincipalUnitGroup.residueTeichmullerLift F y
LocalFieldTheory.DiscreteValuationField.CompleteDVF.higherPrincipalUnitGroup.residueTeichmullerLift_isRoot_X_pow_card_sub_X

Every residue Teichmüller lift is a root of the polynomial X^q - X, where q is the residue-field cardinality.

Source context 11 commands

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

namespace LocalFieldTheory
open ValuationTheory
open ValuationTheory.DiscreteValuationField.ResidueField
noncomputable section
open scoped BigOperators
universe u v
namespace DiscreteValuationField
namespace CompleteDVF
variable {K : Type u} [Field K]
namespace higherPrincipalUnitGroup
variable (F : ValuationTheory.DiscreteValuationField.CompleteDVF.{u, v} K)
theorem residueTeichmullerLift_isRoot_X_pow_card_sub_X
    [Finite F.residueField] (y : F.residueField) :
    (Polynomial.X ^ Nat.card F.residueField - Polynomial.X :
        Polynomial F.valuationSubring).IsRoot
      (higherPrincipalUnitGroup.residueTeichmullerLift F y)
LocalFieldTheory.DiscreteValuationField.CompleteDVF.higherPrincipalUnitGroup.residueTeichmullerRootPolynomial_derivative_eval_isUnit_of_charP

In equal characteristic, T^q - T has unit derivative at every Teichmuller representative.

Source context 11 commands

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

namespace LocalFieldTheory
open ValuationTheory
open ValuationTheory.DiscreteValuationField.ResidueField
noncomputable section
open scoped BigOperators
universe u v
namespace DiscreteValuationField
namespace CompleteDVF
variable {K : Type u} [Field K]
namespace higherPrincipalUnitGroup
variable (F : ValuationTheory.DiscreteValuationField.CompleteDVF.{u, v} K)
theorem residueTeichmullerRootPolynomial_derivative_eval_isUnit_of_charP
    [Finite F.residueField] (p : ℕ) [Fact p.Prime]
    [CharP F.valuationSubring p] {n : ℕ+}
    (hcard : Nat.card F.residueField = p ^ (n : ℕ))
    (y : F.residueField) :
    IsUnit
      (((Polynomial.X ^ Nat.card F.residueField - Polynomial.X :
          Polynomial F.valuationSubring).derivative).eval
        (higherPrincipalUnitGroup.residueTeichmullerLift F y))
LocalFieldTheory.DiscreteValuationField.CompleteDVF.higherPrincipalUnitGroup.residueTeichmullerLift_add_of_charP

In equal characteristic, the Teichmuller lift from the finite residue field to the valuation ring is additive.

Source context 11 commands

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

namespace LocalFieldTheory
open ValuationTheory
open ValuationTheory.DiscreteValuationField.ResidueField
noncomputable section
open scoped BigOperators
universe u v
namespace DiscreteValuationField
namespace CompleteDVF
variable {K : Type u} [Field K]
namespace higherPrincipalUnitGroup
variable (F : ValuationTheory.DiscreteValuationField.CompleteDVF.{u, v} K)
theorem residueTeichmullerLift_add_of_charP [Finite F.residueField]
    (p : ℕ) [Fact p.Prime] [CharP F.valuationSubring p] {n : ℕ+}
    (hcard : Nat.card F.residueField = p ^ (n : ℕ))
    (x y : F.residueField) :
    higherPrincipalUnitGroup.residueTeichmullerLift F (x + y) =
      higherPrincipalUnitGroup.residueTeichmullerLift F x +
        higherPrincipalUnitGroup.residueTeichmullerLift F y
LocalFieldTheory.DiscreteValuationField.CompleteDVF.higherPrincipalUnitGroup.residueTeichmullerRingHomOfCharP

In equal characteristic, the Teichmuller lift is a ring homomorphic coefficient-field section of the residue map.

Source context 11 commands

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

namespace LocalFieldTheory
open ValuationTheory
open ValuationTheory.DiscreteValuationField.ResidueField
noncomputable section
open scoped BigOperators
universe u v
namespace DiscreteValuationField
namespace CompleteDVF
variable {K : Type u} [Field K]
namespace higherPrincipalUnitGroup
variable (F : ValuationTheory.DiscreteValuationField.CompleteDVF.{u, v} K)
def residueTeichmullerRingHomOfCharP
    [Finite F.residueField] (p : ℕ) [Fact p.Prime]
    [CharP F.valuationSubring p] {n : ℕ+}
    (hcard : Nat.card F.residueField = p ^ (n : ℕ)) :
    F.residueField →+* F.valuationSubring where
  toFun := higherPrincipalUnitGroup.residueTeichmullerLift F
  map_zero' := by
    exact higherPrincipalUnitGroup.residueTeichmullerLift_zero (F := F)
  map_one' := by
    exact higherPrincipalUnitGroup.residueTeichmullerLift_one (F := F)
  map_mul' := fun x y =>
    higherPrincipalUnitGroup.residueTeichmullerLift_mul (F := F) x y
  map_add' := fun x y =>
    higherPrincipalUnitGroup.residueTeichmullerLift_add_of_charP
      (F := F) p hcard x y
LocalFieldTheory.DiscreteValuationField.CompleteDVF.higherPrincipalUnitGroup.residueTeichmullerRingHomOfCharP_apply

The defining evaluation formula for residueTeichmullerRingHomOfCharP is higherPrincipalUnitGroup.residueTeichmullerRingHomOfCharP (F := F) p hcard x = higherPrincipalUnitGroup.residueTeichmullerLift F x.

Source context 11 commands

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

namespace LocalFieldTheory
open ValuationTheory
open ValuationTheory.DiscreteValuationField.ResidueField
noncomputable section
open scoped BigOperators
universe u v
namespace DiscreteValuationField
namespace CompleteDVF
variable {K : Type u} [Field K]
namespace higherPrincipalUnitGroup
variable (F : ValuationTheory.DiscreteValuationField.CompleteDVF.{u, v} K)
theorem residueTeichmullerRingHomOfCharP_apply
    [Finite F.residueField] (p : ℕ) [Fact p.Prime]
    [CharP F.valuationSubring p] {n : ℕ+}
    (hcard : Nat.card F.residueField = p ^ (n : ℕ))
    (x : F.residueField) :
    higherPrincipalUnitGroup.residueTeichmullerRingHomOfCharP
        (F := F) p hcard x =
      higherPrincipalUnitGroup.residueTeichmullerLift F x
LocalFieldTheory.DiscreteValuationField.CompleteDVF.higherPrincipalUnitGroup.residueMap_comp_residueTeichmullerRingHomOfCharP

Establishes the identity F.residueMap.comp (higherPrincipalUnitGroup.residueTeichmullerRingHomOfCharP (F := F) p hcard) = RingHom.id F.residueField.

Source context 11 commands

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

namespace LocalFieldTheory
open ValuationTheory
open ValuationTheory.DiscreteValuationField.ResidueField
noncomputable section
open scoped BigOperators
universe u v
namespace DiscreteValuationField
namespace CompleteDVF
variable {K : Type u} [Field K]
namespace higherPrincipalUnitGroup
variable (F : ValuationTheory.DiscreteValuationField.CompleteDVF.{u, v} K)
theorem residueMap_comp_residueTeichmullerRingHomOfCharP
    [Finite F.residueField] (p : ℕ) [Fact p.Prime]
    [CharP F.valuationSubring p] {n : ℕ+}
    (hcard : Nat.card F.residueField = p ^ (n : ℕ)) :
    F.residueMap.comp
        (higherPrincipalUnitGroup.residueTeichmullerRingHomOfCharP
          (F := F) p hcard) =
      RingHom.id F.residueField
LocalFieldTheory.DiscreteValuationField.CompleteDVF.higherPrincipalUnitGroup.residueTeichmullerFieldHomOfCharP

The corresponding coefficient-field embedding into the fraction field.

Source context 11 commands

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

namespace LocalFieldTheory
open ValuationTheory
open ValuationTheory.DiscreteValuationField.ResidueField
noncomputable section
open scoped BigOperators
universe u v
namespace DiscreteValuationField
namespace CompleteDVF
variable {K : Type u} [Field K]
namespace higherPrincipalUnitGroup
variable (F : ValuationTheory.DiscreteValuationField.CompleteDVF.{u, v} K)
def residueTeichmullerFieldHomOfCharP
    [Finite F.residueField] (p : ℕ) [Fact p.Prime]
    [CharP F.valuationSubring p] {n : ℕ+}
    (hcard : Nat.card F.residueField = p ^ (n : ℕ)) :
    F.residueField →+* K
LocalFieldTheory.DiscreteValuationField.CompleteDVF.higherPrincipalUnitGroup.residueTeichmullerFieldHomOfCharP_apply

The defining evaluation formula for residueTeichmullerFieldHomOfCharP is higherPrincipalUnitGroup.residueTeichmullerFieldHomOfCharP (F := F) p hcard x = (higherPrincipalUnitGroup.residueTeichmullerLift F x : K).

Source context 11 commands

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

namespace LocalFieldTheory
open ValuationTheory
open ValuationTheory.DiscreteValuationField.ResidueField
noncomputable section
open scoped BigOperators
universe u v
namespace DiscreteValuationField
namespace CompleteDVF
variable {K : Type u} [Field K]
namespace higherPrincipalUnitGroup
variable (F : ValuationTheory.DiscreteValuationField.CompleteDVF.{u, v} K)
theorem residueTeichmullerFieldHomOfCharP_apply
    [Finite F.residueField] (p : ℕ) [Fact p.Prime]
    [CharP F.valuationSubring p] {n : ℕ+}
    (hcard : Nat.card F.residueField = p ^ (n : ℕ))
    (x : F.residueField) :
    higherPrincipalUnitGroup.residueTeichmullerFieldHomOfCharP
        (F := F) p hcard x =
      (higherPrincipalUnitGroup.residueTeichmullerLift F x : K)