Module

AutomorphismTransport.lean

Nyll.ValuedFieldTheory.LocalField.DiscreteValuationField.PrincipalUnits.AutomorphismTransport
17 declarations indexed from sourceView source ↗

Automorphism transport for principal units

A field automorphism preserving the chosen valuation ring acts on the valuation ring, its residue field, its units, and every principal-unit quotient.

Declarations

LocalFieldTheory.DiscreteValuationField.CompleteDVF.higherPrincipalUnitGroup.valuationSubringRingEquivOfPreserves

A field automorphism preserving the chosen valuation ring induces a ring automorphism of the valuation ring. This is the unit/residue source used before invoking local reciprocity in the local-field arguments.

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 valuationSubringRingEquivOfPreserves
    (e : K ≃+* K)
    (hmem :
      ∀ x : K,
        x ∈ F.valuation.valuationSubring ↔
          e x ∈ F.valuation.valuationSubring) :
    F.valuationSubring ≃+* F.valuationSubring
LocalFieldTheory.DiscreteValuationField.CompleteDVF.higherPrincipalUnitGroup.valuationSubringRingEquivOfPreserves_mem_maximalIdeal_pow_iff

A valuation-ring-preserving field automorphism preserves every power of the maximal ideal of the chosen valuation ring.

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 valuationSubringRingEquivOfPreserves_mem_maximalIdeal_pow_iff
    (e : K ≃+* K)
    (hmem :
      ∀ x : K,
        x ∈ F.valuation.valuationSubring ↔
          e x ∈ F.valuation.valuationSubring)
    (n : ℕ) (x : F.valuationSubring) :
    valuationSubringRingEquivOfPreserves F e hmem x ∈ F.maximalIdeal ^ n ↔
      x ∈ F.maximalIdeal ^ n
LocalFieldTheory.DiscreteValuationField.CompleteDVF.higherPrincipalUnitGroup.valuationSubringResidueFieldEquivOfPreserves

The residue-field automorphism induced by a field automorphism preserving the chosen valuation ring.

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 valuationSubringResidueFieldEquivOfPreserves
    (e : K ≃+* K)
    (hmem :
      ∀ x : K,
        x ∈ F.valuation.valuationSubring ↔
          e x ∈ F.valuation.valuationSubring) :
    F.residueField ≃+* F.residueField
LocalFieldTheory.DiscreteValuationField.CompleteDVF.higherPrincipalUnitGroup.valuationSubringResidueFieldEquivOfPreserves_apply_residue

Establishes the identity valuationSubringResidueFieldEquivOfPreserves F e hmem (F.residueMap x) = F.residueMap (valuationSubringRingEquivOfPreserves F e hmem 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 valuationSubringResidueFieldEquivOfPreserves_apply_residue
    (e : K ≃+* K)
    (hmem :
      ∀ x : K,
        x ∈ F.valuation.valuationSubring ↔
          e x ∈ F.valuation.valuationSubring)
    (x : F.valuationSubring) :
    valuationSubringResidueFieldEquivOfPreserves F e hmem (F.residueMap x) =
      F.residueMap (valuationSubringRingEquivOfPreserves F e hmem x)
LocalFieldTheory.DiscreteValuationField.CompleteDVF.higherPrincipalUnitGroup.valuationSubringUnitEquivOfPreserves

The induced automorphism on valuation-ring units.

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 valuationSubringUnitEquivOfPreserves
    (e : K ≃+* K)
    (hmem :
      ∀ x : K,
        x ∈ F.valuation.valuationSubring ↔
          e x ∈ F.valuation.valuationSubring) :
    F.valuationSubringˣ ≃* F.valuationSubringˣ
LocalFieldTheory.DiscreteValuationField.CompleteDVF.higherPrincipalUnitGroup.valuationSubringUnitEquivOfPreserves_apply

The defining evaluation formula for valuationSubringUnitEquivOfPreserves is ((valuationSubringUnitEquivOfPreserves F e hmem u : F.valuationSubringˣ) : F.valuationSubring) = valuationSubringRingEquivOfPreserves F e hmem (u : F.valuationSubring).

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 valuationSubringUnitEquivOfPreserves_apply
    (e : K ≃+* K)
    (hmem :
      ∀ x : K,
        x ∈ F.valuation.valuationSubring ↔
          e x ∈ F.valuation.valuationSubring)
    (u : F.valuationSubringˣ) :
    ((valuationSubringUnitEquivOfPreserves F e hmem u :
        F.valuationSubringˣ) : F.valuationSubring) =
      valuationSubringRingEquivOfPreserves F e hmem
        (u : F.valuationSubring)
LocalFieldTheory.DiscreteValuationField.CompleteDVF.higherPrincipalUnitGroup.residueUnitHom_valuationSubringUnitEquivOfPreserves

Compatibility between the induced unit action and the induced residue-field action.

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 residueUnitHom_valuationSubringUnitEquivOfPreserves
    (e : K ≃+* K)
    (hmem :
      ∀ x : K,
        x ∈ F.valuation.valuationSubring ↔
          e x ∈ F.valuation.valuationSubring)
    (u : F.valuationSubringˣ) :
    higherPrincipalUnitGroup.residueUnitHom F
        (valuationSubringUnitEquivOfPreserves F e hmem u) =
      Units.map
        (valuationSubringResidueFieldEquivOfPreserves F e hmem).toMonoidHom
        (higherPrincipalUnitGroup.residueUnitHom F u)
LocalFieldTheory.DiscreteValuationField.CompleteDVF.higherPrincipalUnitGroup.valuationSubringUnitEquivOfPreserves_mem_principalUnit_iff

The induced automorphism on valuation-ring units preserves every concrete principal-unit level U^n.

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 valuationSubringUnitEquivOfPreserves_mem_principalUnit_iff
    (e : K ≃+* K)
    (hmem :
      ∀ x : K,
        x ∈ F.valuation.valuationSubring ↔
          e x ∈ F.valuation.valuationSubring)
    (n : ℕ) (u : F.valuationSubringˣ) :
    valuationSubringUnitEquivOfPreserves F e hmem u ∈
        higherPrincipalUnitGroup F n ↔
      u ∈ higherPrincipalUnitGroup F n
LocalFieldTheory.DiscreteValuationField.CompleteDVF.higherPrincipalUnitGroup.higherPrincipalUnitGroup_map_valuationSubringUnitEquivOfPreserves

The subgroup map form of principal-unit preservation for a valuation-ring-preserving field automorphism.

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 higherPrincipalUnitGroup_map_valuationSubringUnitEquivOfPreserves
    (e : K ≃+* K)
    (hmem :
      ∀ x : K,
        x ∈ F.valuation.valuationSubring ↔
          e x ∈ F.valuation.valuationSubring)
    (n : ℕ) :
    (higherPrincipalUnitGroup F n).map
        (valuationSubringUnitEquivOfPreserves F e hmem :
          F.valuationSubringˣ →* F.valuationSubringˣ) =
      higherPrincipalUnitGroup F n
LocalFieldTheory.DiscreteValuationField.CompleteDVF.higherPrincipalUnitGroup.unitsModPrincipalUnitEquivOfPreserves

A valuation-ring-preserving field automorphism induces an automorphism on O^*/U^n for every concrete principal-unit level.

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 unitsModPrincipalUnitEquivOfPreserves
    (e : K ≃+* K)
    (hmem :
      ∀ x : K,
        x ∈ F.valuation.valuationSubring ↔
          e x ∈ F.valuation.valuationSubring)
    (n : ℕ) :
    F.valuationSubringˣ ⧸ higherPrincipalUnitGroup F n ≃*
      F.valuationSubringˣ ⧸ higherPrincipalUnitGroup F n
LocalFieldTheory.DiscreteValuationField.CompleteDVF.higherPrincipalUnitGroup.unitsModPrincipalUnitEquivOfPreserves_mk

Establishes the identity unitsModPrincipalUnitEquivOfPreserves F e hmem n (QuotientGroup.mk' (higherPrincipalUnitGroup F n) u) = QuotientGroup.mk' (higherPrincipalUnitGroup F n) (valuationSubringUnitEquivOfPreserves F e hmem u).

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 unitsModPrincipalUnitEquivOfPreserves_mk
    (e : K ≃+* K)
    (hmem :
      ∀ x : K,
        x ∈ F.valuation.valuationSubring ↔
          e x ∈ F.valuation.valuationSubring)
    (n : ℕ) (u : F.valuationSubringˣ) :
    unitsModPrincipalUnitEquivOfPreserves F e hmem n
        (QuotientGroup.mk' (higherPrincipalUnitGroup F n) u) =
      QuotientGroup.mk' (higherPrincipalUnitGroup F n)
        (valuationSubringUnitEquivOfPreserves F e hmem u)
LocalFieldTheory.DiscreteValuationField.CompleteDVF.higherPrincipalUnitGroup.unitEquiv_div_mem_principalUnit_one_of_residueUnitHom_fixed

If the induced action on residue-field units is trivial, then the valuation-ring unit displacement lies in the first principal-unit group.

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 unitEquiv_div_mem_principalUnit_one_of_residueUnitHom_fixed
    (e : K ≃+* K)
    (hmem :
      ∀ x : K,
        x ∈ F.valuation.valuationSubring ↔
          e x ∈ F.valuation.valuationSubring)
    (hres :
      ∀ u : F.valuationSubringˣ,
        higherPrincipalUnitGroup.residueUnitHom F
            (valuationSubringUnitEquivOfPreserves F e hmem u) =
          higherPrincipalUnitGroup.residueUnitHom F u)
    (u : F.valuationSubringˣ) :
    valuationSubringUnitEquivOfPreserves F e hmem u / u ∈
      higherPrincipalUnitGroup F 1
LocalFieldTheory.DiscreteValuationField.CompleteDVF.higherPrincipalUnitGroup.unitEquiv_mod_principalUnit_one_eq_of_residueUnitHom_fixed

Quotient form of unitEquiv_div_mem_principalUnit_one_of_residueUnitHom_fixed: residue-trivial unit action fixes O^*/U^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 unitEquiv_mod_principalUnit_one_eq_of_residueUnitHom_fixed
    (e : K ≃+* K)
    (hmem :
      ∀ x : K,
        x ∈ F.valuation.valuationSubring ↔
          e x ∈ F.valuation.valuationSubring)
    (hres :
      ∀ u : F.valuationSubringˣ,
        higherPrincipalUnitGroup.residueUnitHom F
            (valuationSubringUnitEquivOfPreserves F e hmem u) =
          higherPrincipalUnitGroup.residueUnitHom F u)
    (u : F.valuationSubringˣ) :
    QuotientGroup.mk' (higherPrincipalUnitGroup F 1)
        (valuationSubringUnitEquivOfPreserves F e hmem u) =
      QuotientGroup.mk' (higherPrincipalUnitGroup F 1) u
LocalFieldTheory.DiscreteValuationField.CompleteDVF.higherPrincipalUnitGroup.unitEquiv_div_mem_principalUnit_one_of_residueFieldEquiv_fixed

Residue-field fixed-point form of unitEquiv_div_mem_principalUnit_one_of_residueUnitHom_fixed: if the induced residue-field automorphism is pointwise trivial, then every valuation-ring unit has first-principal-unit displacement.

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 unitEquiv_div_mem_principalUnit_one_of_residueFieldEquiv_fixed
    (e : K ≃+* K)
    (hmem :
      ∀ x : K,
        x ∈ F.valuation.valuationSubring ↔
          e x ∈ F.valuation.valuationSubring)
    (hres :
      ∀ x : F.residueField,
        valuationSubringResidueFieldEquivOfPreserves F e hmem x = x)
    (u : F.valuationSubringˣ) :
    valuationSubringUnitEquivOfPreserves F e hmem u / u ∈
      higherPrincipalUnitGroup F 1
LocalFieldTheory.DiscreteValuationField.CompleteDVF.higherPrincipalUnitGroup.unitEquiv_mod_principalUnit_one_eq_of_residueFieldEquiv_fixed

Quotient form of unitEquiv_div_mem_principalUnit_one_of_residueFieldEquiv_fixed.

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 unitEquiv_mod_principalUnit_one_eq_of_residueFieldEquiv_fixed
    (e : K ≃+* K)
    (hmem :
      ∀ x : K,
        x ∈ F.valuation.valuationSubring ↔
          e x ∈ F.valuation.valuationSubring)
    (hres :
      ∀ x : F.residueField,
        valuationSubringResidueFieldEquivOfPreserves F e hmem x = x)
    (u : F.valuationSubringˣ) :
    QuotientGroup.mk' (higherPrincipalUnitGroup F 1)
        (valuationSubringUnitEquivOfPreserves F e hmem u) =
      QuotientGroup.mk' (higherPrincipalUnitGroup F 1) u
LocalFieldTheory.DiscreteValuationField.CompleteDVF.higherPrincipalUnitGroup.unitsModPrincipalUnitEquivOfPreserves_one_apply_eq_of_residueFieldEquiv_fixed

If the induced residue-field automorphism is pointwise trivial, then the induced automorphism of O^*/U^1 is pointwise trivial.

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 unitsModPrincipalUnitEquivOfPreserves_one_apply_eq_of_residueFieldEquiv_fixed
    (e : K ≃+* K)
    (hmem :
      ∀ x : K,
        x ∈ F.valuation.valuationSubring ↔
          e x ∈ F.valuation.valuationSubring)
    (hres :
      ∀ x : F.residueField,
        valuationSubringResidueFieldEquivOfPreserves F e hmem x = x)
    (q : F.valuationSubringˣ ⧸ higherPrincipalUnitGroup F 1) :
    unitsModPrincipalUnitEquivOfPreserves F e hmem 1 q = q
LocalFieldTheory.DiscreteValuationField.CompleteDVF.higherPrincipalUnitGroup.unitsModPrincipalUnitEquivOfPreserves_one_eq_refl_of_residueFieldEquiv_fixed

Equivalence form of unitsModPrincipalUnitEquivOfPreserves_one_apply_eq_of_residueFieldEquiv_fixed.

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 unitsModPrincipalUnitEquivOfPreserves_one_eq_refl_of_residueFieldEquiv_fixed
    (e : K ≃+* K)
    (hmem :
      ∀ x : K,
        x ∈ F.valuation.valuationSubring ↔
          e x ∈ F.valuation.valuationSubring)
    (hres :
      ∀ x : F.residueField,
        valuationSubringResidueFieldEquivOfPreserves F e hmem x = x) :
    unitsModPrincipalUnitEquivOfPreserves F e hmem 1 =
      MulEquiv.refl (F.valuationSubringˣ ⧸ higherPrincipalUnitGroup F 1)