Module

FiniteStageTransgressionKernel.lean

Nyll.GaloisCohomology.ProP.FiniteStageTransgressionKernel
8 declarations indexed from sourceView source ↗

Kernel exactness for inflated finite-stage transgression

A primitive for a vanishing inflated class is corrected by finite-stage quotient-section residues. The resulting coboundary datum gives a continuous ambient character extending the original invariant kernel character.

Declarations

ClassFieldTower.ProP.finiteStageKernelTargetTopology
Source context 9 commands

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

open CategoryTheory TopRep ContRepresentation
open scoped Topology
namespace ClassFieldTower.ProP
open ProCGroups ProCGroups.ProC
open ClassFieldTower.Cohomology
noncomputable section
universe u
variable {p : ℕ} [Fact p.Prime]
variable {F : Type u} [Group F] [TopologicalSpace F] [IsTopologicalGroup F]
instance finiteStageKernelTargetTopology
    (R : ClosedSubgroup F)
    (U : OpenNormalSubgroupInClass (FiniteGroupClass.pGroup p) F) :
    TopologicalSpace
      ((F ⧸ (U.1 : Subgroup F)) ⧸ finiteStageImage R U)
ClassFieldTower.ProP.finiteStageKernelTargetDiscrete
Source context 10 commands

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

open CategoryTheory TopRep ContRepresentation
open scoped Topology
namespace ClassFieldTower.ProP
open ProCGroups ProCGroups.ProC
open ClassFieldTower.Cohomology
noncomputable section
universe u
variable {p : ℕ} [Fact p.Prime]
variable {F : Type u} [Group F] [TopologicalSpace F] [IsTopologicalGroup F]
local instance finiteStageKernelTargetTopology
    (R : ClosedSubgroup F)
    (U : OpenNormalSubgroupInClass (FiniteGroupClass.pGroup p) F) :
    TopologicalSpace
      ((F ⧸ (U.1 : Subgroup F)) ⧸ finiteStageImage R U) := ⊥
instance finiteStageKernelTargetDiscrete
    (R : ClosedSubgroup F)
    (U : OpenNormalSubgroupInClass (FiniteGroupClass.pGroup p) F) :
    DiscreteTopology
      ((F ⧸ (U.1 : Subgroup F)) ⧸ finiteStageImage R U)
ClassFieldTower.ProP.finiteStageQuotientMap_out
Source context 11 commands

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

open CategoryTheory TopRep ContRepresentation
open scoped Topology
namespace ClassFieldTower.ProP
open ProCGroups ProCGroups.ProC
open ClassFieldTower.Cohomology
noncomputable section
universe u
variable {p : ℕ} [Fact p.Prime]
variable {F : Type u} [Group F] [TopologicalSpace F] [IsTopologicalGroup F]
local instance finiteStageKernelTargetTopology
    (R : ClosedSubgroup F)
    (U : OpenNormalSubgroupInClass (FiniteGroupClass.pGroup p) F) :
    TopologicalSpace
      ((F ⧸ (U.1 : Subgroup F)) ⧸ finiteStageImage R U) := ⊥
local instance finiteStageKernelTargetDiscrete
    (R : ClosedSubgroup F)
    (U : OpenNormalSubgroupInClass (FiniteGroupClass.pGroup p) F) :
    DiscreteTopology
      ((F ⧸ (U.1 : Subgroup F)) ⧸ finiteStageImage R U) :=
  discreteTopology_bot _
theorem finiteStageQuotientMap_out
    (R : ClosedSubgroup F) [R.Normal]
    (U : OpenNormalSubgroupInClass (FiniteGroupClass.pGroup p) F)
    (q : F ⧸ (R : Subgroup F)) :
    QuotientGroup.mk' (finiteStageImage R U)
        (OpenNormalSubgroup.quotientProj U.1 (Quotient.out q)) =
      finiteStageQuotientMap R U q
ClassFieldTower.ProP.finiteStageSectionResidueValue

The additive character value of the finite-stage residue of a chosen quotient section.

Source context 11 commands

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

open CategoryTheory TopRep ContRepresentation
open scoped Topology
namespace ClassFieldTower.ProP
open ProCGroups ProCGroups.ProC
open ClassFieldTower.Cohomology
noncomputable section
universe u
variable {p : ℕ} [Fact p.Prime]
variable {F : Type u} [Group F] [TopologicalSpace F] [IsTopologicalGroup F]
local instance finiteStageKernelTargetTopology
    (R : ClosedSubgroup F)
    (U : OpenNormalSubgroupInClass (FiniteGroupClass.pGroup p) F) :
    TopologicalSpace
      ((F ⧸ (U.1 : Subgroup F)) ⧸ finiteStageImage R U) := ⊥
local instance finiteStageKernelTargetDiscrete
    (R : ClosedSubgroup F)
    (U : OpenNormalSubgroupInClass (FiniteGroupClass.pGroup p) F) :
    DiscreteTopology
      ((F ⧸ (U.1 : Subgroup F)) ⧸ finiteStageImage R U) :=
  discreteTopology_bot _
def finiteStageSectionResidueValue
    (R : ClosedSubgroup F) [R.Normal]
    (U : OpenNormalSubgroupInClass (FiniteGroupClass.pGroup p) F)
    (χbar : MonoidHom (finiteStageImage R U) (Multiplicative (ZMod p)))
    (q : F ⧸ (R : Subgroup F)) : ZMod p
ClassFieldTower.ProP.quotientSectionResidue_finiteStage_out_mul
Source context 11 commands

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

open CategoryTheory TopRep ContRepresentation
open scoped Topology
namespace ClassFieldTower.ProP
open ProCGroups ProCGroups.ProC
open ClassFieldTower.Cohomology
noncomputable section
universe u
variable {p : ℕ} [Fact p.Prime]
variable {F : Type u} [Group F] [TopologicalSpace F] [IsTopologicalGroup F]
local instance finiteStageKernelTargetTopology
    (R : ClosedSubgroup F)
    (U : OpenNormalSubgroupInClass (FiniteGroupClass.pGroup p) F) :
    TopologicalSpace
      ((F ⧸ (U.1 : Subgroup F)) ⧸ finiteStageImage R U) := ⊥
local instance finiteStageKernelTargetDiscrete
    (R : ClosedSubgroup F)
    (U : OpenNormalSubgroupInClass (FiniteGroupClass.pGroup p) F) :
    DiscreteTopology
      ((F ⧸ (U.1 : Subgroup F)) ⧸ finiteStageImage R U) :=
  discreteTopology_bot _
theorem quotientSectionResidue_finiteStage_out_mul
    (R : ClosedSubgroup F) [R.Normal]
    (U : OpenNormalSubgroupInClass (FiniteGroupClass.pGroup p) F)
    (q r : F ⧸ (R : Subgroup F)) :
    quotientSectionResidue (finiteStageImage R U)
        (OpenNormalSubgroup.quotientProj U.1 (Quotient.out q) *
          OpenNormalSubgroup.quotientProj U.1 (Quotient.out r)) =
      finiteStageImageMap R U (quotientSectionFactor (R : Subgroup F) q r) *
        quotientSectionResidue (finiteStageImage R U)
          (OpenNormalSubgroup.quotientProj U.1 (Quotient.out (q * r)))
ClassFieldTower.ProP.quotientSectionResidue_finiteStage_decomposition
Source context 11 commands

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

open CategoryTheory TopRep ContRepresentation
open scoped Topology
namespace ClassFieldTower.ProP
open ProCGroups ProCGroups.ProC
open ClassFieldTower.Cohomology
noncomputable section
universe u
variable {p : ℕ} [Fact p.Prime]
variable {F : Type u} [Group F] [TopologicalSpace F] [IsTopologicalGroup F]
local instance finiteStageKernelTargetTopology
    (R : ClosedSubgroup F)
    (U : OpenNormalSubgroupInClass (FiniteGroupClass.pGroup p) F) :
    TopologicalSpace
      ((F ⧸ (U.1 : Subgroup F)) ⧸ finiteStageImage R U) := ⊥
local instance finiteStageKernelTargetDiscrete
    (R : ClosedSubgroup F)
    (U : OpenNormalSubgroupInClass (FiniteGroupClass.pGroup p) F) :
    DiscreteTopology
      ((F ⧸ (U.1 : Subgroup F)) ⧸ finiteStageImage R U) :=
  discreteTopology_bot _
theorem quotientSectionResidue_finiteStage_decomposition
    (R : ClosedSubgroup F) [R.Normal]
    (U : OpenNormalSubgroupInClass (FiniteGroupClass.pGroup p) F)
    (g : F) :
    quotientSectionResidue (finiteStageImage R U)
        (OpenNormalSubgroup.quotientProj U.1 g) =
      finiteStageImageMap R U
          (quotientSectionResidue (R : Subgroup F) g) *
        quotientSectionResidue (finiteStageImage R U)
          (OpenNormalSubgroup.quotientProj U.1
            (Quotient.out (QuotientGroup.mk' (R : Subgroup F) g)))
ClassFieldTower.ProP.transgressionFactor_eq_inflated_add_residue_boundary
Source context 11 commands

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

open CategoryTheory TopRep ContRepresentation
open scoped Topology
namespace ClassFieldTower.ProP
open ProCGroups ProCGroups.ProC
open ClassFieldTower.Cohomology
noncomputable section
universe u
variable {p : ℕ} [Fact p.Prime]
variable {F : Type u} [Group F] [TopologicalSpace F] [IsTopologicalGroup F]
local instance finiteStageKernelTargetTopology
    (R : ClosedSubgroup F)
    (U : OpenNormalSubgroupInClass (FiniteGroupClass.pGroup p) F) :
    TopologicalSpace
      ((F ⧸ (U.1 : Subgroup F)) ⧸ finiteStageImage R U) := ⊥
local instance finiteStageKernelTargetDiscrete
    (R : ClosedSubgroup F)
    (U : OpenNormalSubgroupInClass (FiniteGroupClass.pGroup p) F) :
    DiscreteTopology
      ((F ⧸ (U.1 : Subgroup F)) ⧸ finiteStageImage R U) :=
  discreteTopology_bot _
theorem transgressionFactor_eq_inflated_add_residue_boundary
    (R : ClosedSubgroup F) [R.Normal]
    (U : OpenNormalSubgroupInClass (FiniteGroupClass.pGroup p) F)
    (χbar : MonoidHom (finiteStageImage R U) (Multiplicative (ZMod p)))
    (hχbar : ∀ (g : F ⧸ (U.1 : Subgroup F)) (n : finiteStageImage R U),
      χbar (MulAut.conjNormal g n) = χbar n)
    (χ : R →ₜ* Multiplicative (ZMod p))
    (hpull : χbar.comp (finiteStageImageMap R U) = χ.toMonoidHom)
    (q r : F ⧸ (R : Subgroup F)) :
    transgressionFactor (R : Subgroup F) χ.toMonoidHom q r =
      transgressionFactor (finiteStageImage R U) χbar
          (finiteStageQuotientMap R U q) (finiteStageQuotientMap R U r) +
        (finiteStageSectionResidueValue R U χbar r -
          finiteStageSectionResidueValue R U χbar (q * r) +
            finiteStageSectionResidueValue R U χbar q)
ClassFieldTower.ProP.exists_continuous_extension_of_inflatedFiniteTransgressionClass_eq_zero

Vanishing of the inflated finite-stage transgression class produces a continuous ambient character extending the original pullback character.

Source context 11 commands

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

open CategoryTheory TopRep ContRepresentation
open scoped Topology
namespace ClassFieldTower.ProP
open ProCGroups ProCGroups.ProC
open ClassFieldTower.Cohomology
noncomputable section
universe u
variable {p : ℕ} [Fact p.Prime]
variable {F : Type u} [Group F] [TopologicalSpace F] [IsTopologicalGroup F]
local instance finiteStageKernelTargetTopology
    (R : ClosedSubgroup F)
    (U : OpenNormalSubgroupInClass (FiniteGroupClass.pGroup p) F) :
    TopologicalSpace
      ((F ⧸ (U.1 : Subgroup F)) ⧸ finiteStageImage R U) := ⊥
local instance finiteStageKernelTargetDiscrete
    (R : ClosedSubgroup F)
    (U : OpenNormalSubgroupInClass (FiniteGroupClass.pGroup p) F) :
    DiscreteTopology
      ((F ⧸ (U.1 : Subgroup F)) ⧸ finiteStageImage R U) :=
  discreteTopology_bot _
theorem exists_continuous_extension_of_inflatedFiniteTransgressionClass_eq_zero
    (R : ClosedSubgroup F) [R.Normal]
    (U : OpenNormalSubgroupInClass (FiniteGroupClass.pGroup p) F)
    (χbar : MonoidHom (finiteStageImage R U) (Multiplicative (ZMod p)))
    (hχbar : ∀ (g : F ⧸ (U.1 : Subgroup F)) (n : finiteStageImage R U),
      χbar (MulAut.conjNormal g n) = χbar n)
    (χ : R →ₜ* Multiplicative (ZMod p))
    (hχ : ∀ (f : F) (r : R), χ (MulAut.conjNormal f r) = χ r)
    (hpull : χbar.comp (finiteStageImageMap R U) = χ.toMonoidHom)
    (hzero : inflatedFiniteTransgressionClass R U χbar hχbar = 0) :
    ∃ ψ : F →ₜ* Multiplicative (ZMod p),
      ψ.comp (subgroupInclusion (R : Subgroup F)) = χ