Module

LocalUnramifiedArtinKummerRange.lean

Nyll.SawinTotallyRealTowers.UnramifiedProPRelationRank.Kummer.LocalUnramifiedArtinKummerRange
12 declarations indexed from sourceView source ↗

Unramified Artin--Kummer duality and the valuation line

The intrinsic inertia-trivial subspace of local continuous H¹ is sent by the Artin--Kummer pairing precisely onto the valuation line in the dual. The proof uses actual unramified Kummer extensions and their Frobenius action, and applies also when the residue characteristic is the coefficient prime.

Declarations

ClassFieldTower.Martinet.Shafarevich.localUnramifiedArtinKummerRangeTopology
Source context 6 commands

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

noncomputable section
namespace ClassFieldTower.Martinet.Shafarevich
open ClassFieldTower.ProP KummerTheory LocalClassFieldTheory
variable (K : Type) [Field K] [CharZero K]
variable [ValuativeRel K] [TopologicalSpace K] [IsNonarchimedeanLocalField K]
variable (n : ℕ+) [Fact ((n : ℕ).Prime)]
instance localUnramifiedArtinKummerRangeTopology : TopologicalSpace (ZMod (n : ℕ))
ClassFieldTower.Martinet.Shafarevich.localUnramifiedArtinKummerRangeDiscreteTopology
Source context 7 commands

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

noncomputable section
namespace ClassFieldTower.Martinet.Shafarevich
open ClassFieldTower.ProP KummerTheory LocalClassFieldTheory
variable (K : Type) [Field K] [CharZero K]
variable [ValuativeRel K] [TopologicalSpace K] [IsNonarchimedeanLocalField K]
variable (n : ℕ+) [Fact ((n : ℕ).Prime)]
local instance localUnramifiedArtinKummerRangeTopology : TopologicalSpace (ZMod (n : ℕ)) := ⊥
instance localUnramifiedArtinKummerRangeDiscreteTopology : DiscreteTopology (ZMod (n : ℕ))
ClassFieldTower.Martinet.Shafarevich.localUnramifiedArtinKummerRangeModule
Source context 8 commands

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

noncomputable section
namespace ClassFieldTower.Martinet.Shafarevich
open ClassFieldTower.ProP KummerTheory LocalClassFieldTheory
variable (K : Type) [Field K] [CharZero K]
variable [ValuativeRel K] [TopologicalSpace K] [IsNonarchimedeanLocalField K]
variable (n : ℕ+) [Fact ((n : ℕ).Prime)]
local instance localUnramifiedArtinKummerRangeTopology : TopologicalSpace (ZMod (n : ℕ)) := ⊥
local instance localUnramifiedArtinKummerRangeDiscreteTopology : DiscreteTopology (ZMod (n : ℕ)) :=
  discreteTopology_bot _
instance localUnramifiedArtinKummerRangeModule
    {G : Type*} [Group G] [TopologicalSpace G] [IsTopologicalGroup G] :
    Module (ZMod (n : ℕ)) (ContinuousH1ZMod (p := (n : ℕ)) (G := G))
ClassFieldTower.Martinet.Shafarevich.localStandardUnramifiedH1

Intrinsic unramified H¹, written in the standard absolute-Galois model.

Source context 9 commands

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

noncomputable section
namespace ClassFieldTower.Martinet.Shafarevich
open ClassFieldTower.ProP KummerTheory LocalClassFieldTheory
variable (K : Type) [Field K] [CharZero K]
variable [ValuativeRel K] [TopologicalSpace K] [IsNonarchimedeanLocalField K]
variable (n : ℕ+) [Fact ((n : ℕ).Prime)]
local instance localUnramifiedArtinKummerRangeTopology : TopologicalSpace (ZMod (n : ℕ)) := ⊥
local instance localUnramifiedArtinKummerRangeDiscreteTopology : DiscreteTopology (ZMod (n : ℕ)) :=
  discreteTopology_bot _
local instance localUnramifiedArtinKummerRangeModule
    {G : Type*} [Group G] [TopologicalSpace G] [IsTopologicalGroup G] :
    Module (ZMod (n : ℕ)) (ContinuousH1ZMod (p := (n : ℕ)) (G := G)) := continuousH1ZModModule
def localStandardUnramifiedH1 :
    Submodule (ZMod (n : ℕ))
      (ContinuousH1ZMod (p := (n : ℕ)) (G := Field.absoluteGaloisGroup K))
ClassFieldTower.Martinet.Shafarevich.isUnramifiedChosenSimpleKummer_of_kummerH1_mem

An inertia-trivial Kummer character defines an actually unramified chosen simple extension, including in residue characteristic n.

Source context 9 commands

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

noncomputable section
namespace ClassFieldTower.Martinet.Shafarevich
open ClassFieldTower.ProP KummerTheory LocalClassFieldTheory
variable (K : Type) [Field K] [CharZero K]
variable [ValuativeRel K] [TopologicalSpace K] [IsNonarchimedeanLocalField K]
variable (n : ℕ+) [Fact ((n : ℕ).Prime)]
local instance localUnramifiedArtinKummerRangeTopology : TopologicalSpace (ZMod (n : ℕ)) := ⊥
local instance localUnramifiedArtinKummerRangeDiscreteTopology : DiscreteTopology (ZMod (n : ℕ)) :=
  discreteTopology_bot _
local instance localUnramifiedArtinKummerRangeModule
    {G : Type*} [Group G] [TopologicalSpace G] [IsTopologicalGroup G] :
    Module (ZMod (n : ℕ)) (ContinuousH1ZMod (p := (n : ℕ)) (G := G)) := continuousH1ZModModule
theorem isUnramifiedChosenSimpleKummer_of_kummerH1_mem
    (hmu : (primitiveRoots (n : ℕ) K).Nonempty) (a : Kˣ)
    (ha : absoluteKummerContinuousH1LinearEquiv K (n : ℕ) hmu
      (Additive.ofMul
        (QuotientGroup.mk' (powMonoidHom (n : ℕ) : Kˣ →* Kˣ).range a)) ∈
          localStandardUnramifiedH1 K n) :
    IsUnramifiedChosenSimpleKummer K n
      (Nat.cast_ne_zero.mpr (Fact.out : (n : ℕ).Prime).ne_zero) a
ClassFieldTower.Martinet.Shafarevich.localStandardH1Valuation

The local valuation, transported through absolute Kummer theory.

Source context 9 commands

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

noncomputable section
namespace ClassFieldTower.Martinet.Shafarevich
open ClassFieldTower.ProP KummerTheory LocalClassFieldTheory
variable (K : Type) [Field K] [CharZero K]
variable [ValuativeRel K] [TopologicalSpace K] [IsNonarchimedeanLocalField K]
variable (n : ℕ+) [Fact ((n : ℕ).Prime)]
local instance localUnramifiedArtinKummerRangeTopology : TopologicalSpace (ZMod (n : ℕ)) := ⊥
local instance localUnramifiedArtinKummerRangeDiscreteTopology : DiscreteTopology (ZMod (n : ℕ)) :=
  discreteTopology_bot _
local instance localUnramifiedArtinKummerRangeModule
    {G : Type*} [Group G] [TopologicalSpace G] [IsTopologicalGroup G] :
    Module (ZMod (n : ℕ)) (ContinuousH1ZMod (p := (n : ℕ)) (G := G)) := continuousH1ZModModule
def localStandardH1Valuation
    (hmu : (primitiveRoots (n : ℕ) K).Nonempty) :
    ContinuousH1ZMod (p := (n : ℕ)) (G := Field.absoluteGaloisGroup K) →ₗ[ZMod (n : ℕ)]
      ZMod (n : ℕ)
ClassFieldTower.Martinet.Shafarevich.localStandardH1ValuationDualEmbedding

The valuation line in the dual of standard local H¹.

Source context 9 commands

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

noncomputable section
namespace ClassFieldTower.Martinet.Shafarevich
open ClassFieldTower.ProP KummerTheory LocalClassFieldTheory
variable (K : Type) [Field K] [CharZero K]
variable [ValuativeRel K] [TopologicalSpace K] [IsNonarchimedeanLocalField K]
variable (n : ℕ+) [Fact ((n : ℕ).Prime)]
local instance localUnramifiedArtinKummerRangeTopology : TopologicalSpace (ZMod (n : ℕ)) := ⊥
local instance localUnramifiedArtinKummerRangeDiscreteTopology : DiscreteTopology (ZMod (n : ℕ)) :=
  discreteTopology_bot _
local instance localUnramifiedArtinKummerRangeModule
    {G : Type*} [Group G] [TopologicalSpace G] [IsTopologicalGroup G] :
    Module (ZMod (n : ℕ)) (ContinuousH1ZMod (p := (n : ℕ)) (G := G)) := continuousH1ZModModule
def localStandardH1ValuationDualEmbedding
    (hmu : (primitiveRoots (n : ℕ) K).Nonempty) :
    ZMod (n : ℕ) →ₗ[ZMod (n : ℕ)] Module.Dual (ZMod (n : ℕ))
      (ContinuousH1ZMod (p := (n : ℕ)) (G := Field.absoluteGaloisGroup K))
ClassFieldTower.Martinet.Shafarevich.localStandardH1ValuationDualEmbedding_apply
Source context 9 commands

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

noncomputable section
namespace ClassFieldTower.Martinet.Shafarevich
open ClassFieldTower.ProP KummerTheory LocalClassFieldTheory
variable (K : Type) [Field K] [CharZero K]
variable [ValuativeRel K] [TopologicalSpace K] [IsNonarchimedeanLocalField K]
variable (n : ℕ+) [Fact ((n : ℕ).Prime)]
local instance localUnramifiedArtinKummerRangeTopology : TopologicalSpace (ZMod (n : ℕ)) := ⊥
local instance localUnramifiedArtinKummerRangeDiscreteTopology : DiscreteTopology (ZMod (n : ℕ)) :=
  discreteTopology_bot _
local instance localUnramifiedArtinKummerRangeModule
    {G : Type*} [Group G] [TopologicalSpace G] [IsTopologicalGroup G] :
    Module (ZMod (n : ℕ)) (ContinuousH1ZMod (p := (n : ℕ)) (G := G)) := continuousH1ZModModule
theorem localStandardH1ValuationDualEmbedding_apply
    (hmu : (primitiveRoots (n : ℕ) K).Nonempty) (a : ZMod (n : ℕ))
    (chi : ContinuousH1ZMod (p := (n : ℕ)) (G := Field.absoluteGaloisGroup K)) :
    localStandardH1ValuationDualEmbedding K n hmu a chi =
      a * localStandardH1Valuation K n hmu chi
ClassFieldTower.Martinet.Shafarevich.localArtinKummerH1DualEmbedding_mk_unramified

The local Artin--Kummer functional of an unramified radical is the Frobenius-scaled valuation functional on H¹.

Source context 9 commands

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

noncomputable section
namespace ClassFieldTower.Martinet.Shafarevich
open ClassFieldTower.ProP KummerTheory LocalClassFieldTheory
variable (K : Type) [Field K] [CharZero K]
variable [ValuativeRel K] [TopologicalSpace K] [IsNonarchimedeanLocalField K]
variable (n : ℕ+) [Fact ((n : ℕ).Prime)]
local instance localUnramifiedArtinKummerRangeTopology : TopologicalSpace (ZMod (n : ℕ)) := ⊥
local instance localUnramifiedArtinKummerRangeDiscreteTopology : DiscreteTopology (ZMod (n : ℕ)) :=
  discreteTopology_bot _
local instance localUnramifiedArtinKummerRangeModule
    {G : Type*} [Group G] [TopologicalSpace G] [IsTopologicalGroup G] :
    Module (ZMod (n : ℕ)) (ContinuousH1ZMod (p := (n : ℕ)) (G := G)) := continuousH1ZModModule
theorem localArtinKummerH1DualEmbedding_mk_unramified
    (hmu : (primitiveRoots (n : ℕ) K).Nonempty) (a : Kˣ)
    (ha : IsUnramifiedChosenSimpleKummer K n
      (Nat.cast_ne_zero.mpr (Fact.out : (n : ℕ).Prime).ne_zero) a) :
    localArtinKummerH1DualEmbedding K n hmu
        (absoluteKummerContinuousH1LinearEquiv K (n : ℕ) hmu
          (Additive.ofMul
            (QuotientGroup.mk' (powMonoidHom (n : ℕ) : Kˣ →* Kˣ).range a))) =
      localStandardH1ValuationDualEmbedding K n hmu
        (unramifiedChosenSimpleKummerFrobeniusScalar K n hmu a ha)
ClassFieldTower.Martinet.Shafarevich.localArtinKummerH1DualEmbedding_mem_valuation_range

Intrinsic unramified classes map into the valuation dual line under local Artin--Kummer duality.

Source context 9 commands

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

noncomputable section
namespace ClassFieldTower.Martinet.Shafarevich
open ClassFieldTower.ProP KummerTheory LocalClassFieldTheory
variable (K : Type) [Field K] [CharZero K]
variable [ValuativeRel K] [TopologicalSpace K] [IsNonarchimedeanLocalField K]
variable (n : ℕ+) [Fact ((n : ℕ).Prime)]
local instance localUnramifiedArtinKummerRangeTopology : TopologicalSpace (ZMod (n : ℕ)) := ⊥
local instance localUnramifiedArtinKummerRangeDiscreteTopology : DiscreteTopology (ZMod (n : ℕ)) :=
  discreteTopology_bot _
local instance localUnramifiedArtinKummerRangeModule
    {G : Type*} [Group G] [TopologicalSpace G] [IsTopologicalGroup G] :
    Module (ZMod (n : ℕ)) (ContinuousH1ZMod (p := (n : ℕ)) (G := G)) := continuousH1ZModModule
theorem localArtinKummerH1DualEmbedding_mem_valuation_range
    (hmu : (primitiveRoots (n : ℕ) K).Nonempty)
    (chi : ContinuousH1ZMod (p := (n : ℕ)) (G := Field.absoluteGaloisGroup K))
    (hchi : chi ∈ localStandardUnramifiedH1 K n) :
    localArtinKummerH1DualEmbedding K n hmu chi ∈
      LinearMap.range (localStandardH1ValuationDualEmbedding K n hmu)
ClassFieldTower.Martinet.Shafarevich.localStandardUnramifiedH1_exists_ne_zero

The intrinsic unramified line is not zero.

Source context 10 commands

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

noncomputable section
namespace ClassFieldTower.Martinet.Shafarevich
open ClassFieldTower.ProP KummerTheory LocalClassFieldTheory
variable (K : Type) [Field K] [CharZero K]
variable [ValuativeRel K] [TopologicalSpace K] [IsNonarchimedeanLocalField K]
variable (n : ℕ+) [Fact ((n : ℕ).Prime)]
local instance localUnramifiedArtinKummerRangeTopology : TopologicalSpace (ZMod (n : ℕ)) := ⊥
local instance localUnramifiedArtinKummerRangeDiscreteTopology : DiscreteTopology (ZMod (n : ℕ)) :=
  discreteTopology_bot _
local instance localUnramifiedArtinKummerRangeModule
    {G : Type*} [Group G] [TopologicalSpace G] [IsTopologicalGroup G] :
    Module (ZMod (n : ℕ)) (ContinuousH1ZMod (p := (n : ℕ)) (G := G)) := continuousH1ZModModule
omit [CharZero K] in
theorem localStandardUnramifiedH1_exists_ne_zero :
    ∃ chi : ContinuousH1ZMod (p := (n : ℕ)) (G := Field.absoluteGaloisGroup K),
      chi ∈ localStandardUnramifiedH1 K n ∧ chi ≠ 0
ClassFieldTower.Martinet.Shafarevich.localArtinKummerH1DualEmbedding_unramified_range

Local Artin--Kummer duality takes intrinsic unramified H¹ exactly onto the valuation dual line.

Source context 9 commands

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

noncomputable section
namespace ClassFieldTower.Martinet.Shafarevich
open ClassFieldTower.ProP KummerTheory LocalClassFieldTheory
variable (K : Type) [Field K] [CharZero K]
variable [ValuativeRel K] [TopologicalSpace K] [IsNonarchimedeanLocalField K]
variable (n : ℕ+) [Fact ((n : ℕ).Prime)]
local instance localUnramifiedArtinKummerRangeTopology : TopologicalSpace (ZMod (n : ℕ)) := ⊥
local instance localUnramifiedArtinKummerRangeDiscreteTopology : DiscreteTopology (ZMod (n : ℕ)) :=
  discreteTopology_bot _
local instance localUnramifiedArtinKummerRangeModule
    {G : Type*} [Group G] [TopologicalSpace G] [IsTopologicalGroup G] :
    Module (ZMod (n : ℕ)) (ContinuousH1ZMod (p := (n : ℕ)) (G := G)) := continuousH1ZModModule
theorem localArtinKummerH1DualEmbedding_unramified_range
    (hmu : (primitiveRoots (n : ℕ) K).Nonempty) :
    LinearMap.range
        ((localArtinKummerH1DualEmbedding K n hmu).comp
          (localStandardUnramifiedH1 K n).subtype) =
      LinearMap.range (localStandardH1ValuationDualEmbedding K n hmu)