Module

TruncatedFoxMaps.lean

Nyll.ProCGroups.GolodShafarevich.TruncatedFoxMaps
25 declarations indexed from sourceView source ↗

Truncated mod-p Fox maps

This file descends the completed relation matrix, Fox boundary, and canonical augmentation to the shifted closed-augmentation quotients used in the truncated Golod--Shafarevich sequence.

Declarations

ClassFieldTower.ProP.PresentationModPTruncatedRelationSource

The relation source after passing coordinatewise to shifted truncations.

Source context 10 commands

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

namespace ClassFieldTower.ProP
open CompletedGroupAlgebra
open FoxDifferential
open ProCGroups
noncomputable section
universe u
variable {p d r : ℕ} [Fact p.Prime]
variable {sourceData :
  FreeProC.EpimorphicallyFreeProCGroupOnConvergingSetData.{u, u}
    (FiniteGroupClass.pGroup p)}
variable {G : Type u} [Group G] [TopologicalSpace G] [IsTopologicalGroup G]
variable [CompactSpace G] [T2Space G] [TotallyDisconnectedSpace G]
abbrev PresentationModPTruncatedRelationSource (ν : Fin r → ℕ) (N : ℕ)
ClassFieldTower.ProP.PresentationModPTruncatedFoxCoordinates

The Fox-coordinate module after truncation, with the boundary shift.

Source context 10 commands

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

namespace ClassFieldTower.ProP
open CompletedGroupAlgebra
open FoxDifferential
open ProCGroups
noncomputable section
universe u
variable {p d r : ℕ} [Fact p.Prime]
variable {sourceData :
  FreeProC.EpimorphicallyFreeProCGroupOnConvergingSetData.{u, u}
    (FiniteGroupClass.pGroup p)}
variable {G : Type u} [Group G] [TopologicalSpace G] [IsTopologicalGroup G]
variable [CompactSpace G] [T2Space G] [TotallyDisconnectedSpace G]
abbrev PresentationModPTruncatedFoxCoordinates (N : ℕ)
ClassFieldTower.ProP.presentationModPFoxCoordinateFinEquiv

Reindex the universe-lifted presentation coordinates by Fin d.

Source context 10 commands

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

namespace ClassFieldTower.ProP
open CompletedGroupAlgebra
open FoxDifferential
open ProCGroups
noncomputable section
universe u
variable {p d r : ℕ} [Fact p.Prime]
variable {sourceData :
  FreeProC.EpimorphicallyFreeProCGroupOnConvergingSetData.{u, u}
    (FiniteGroupClass.pGroup p)}
variable {G : Type u} [Group G] [TopologicalSpace G] [IsTopologicalGroup G]
variable [CompactSpace G] [T2Space G] [TotallyDisconnectedSpace G]
def presentationModPFoxCoordinateFinEquiv :
    (Fin d → ModPCompletedGroupAlgebra p G) ≃ₗ[ModPCompletedGroupAlgebra p G]
      PresentationModPFoxCoordinates (p := p) (d := d) (G := G) where
  toFun v i := v i.down
  invFun v i := v (ULift.up i)
  left_inv v := rfl
  right_inv v := by
    funext i
    cases i
    rfl
  map_add' _ _ := rfl
  map_smul' _ _ := rfl
ClassFieldTower.ProP.relationTruncationFamily
Source context 10 commands

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

namespace ClassFieldTower.ProP
open CompletedGroupAlgebra
open FoxDifferential
open ProCGroups
noncomputable section
universe u
variable {p d r : ℕ} [Fact p.Prime]
variable {sourceData :
  FreeProC.EpimorphicallyFreeProCGroupOnConvergingSetData.{u, u}
    (FiniteGroupClass.pGroup p)}
variable {G : Type u} [Group G] [TopologicalSpace G] [IsTopologicalGroup G]
variable [CompactSpace G] [T2Space G] [TotallyDisconnectedSpace G]
abbrev relationTruncationFamily (ν : Fin r → ℕ) (N : ℕ)
    (j : Fin r) : Submodule (ZMod p) (ModPCompletedGroupAlgebra p G)
ClassFieldTower.ProP.foxTruncationFamily
Source context 10 commands

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

namespace ClassFieldTower.ProP
open CompletedGroupAlgebra
open FoxDifferential
open ProCGroups
noncomputable section
universe u
variable {p d r : ℕ} [Fact p.Prime]
variable {sourceData :
  FreeProC.EpimorphicallyFreeProCGroupOnConvergingSetData.{u, u}
    (FiniteGroupClass.pGroup p)}
variable {G : Type u} [Group G] [TopologicalSpace G] [IsTopologicalGroup G]
variable [CompactSpace G] [T2Space G] [TotallyDisconnectedSpace G]
abbrev foxTruncationFamily (N : ℕ) (_i : Fin d) :
    Submodule (ZMod p) (ModPCompletedGroupAlgebra p G)
ClassFieldTower.ProP.relationPiFiltration
Source context 10 commands

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

namespace ClassFieldTower.ProP
open CompletedGroupAlgebra
open FoxDifferential
open ProCGroups
noncomputable section
universe u
variable {p d r : ℕ} [Fact p.Prime]
variable {sourceData :
  FreeProC.EpimorphicallyFreeProCGroupOnConvergingSetData.{u, u}
    (FiniteGroupClass.pGroup p)}
variable {G : Type u} [Group G] [TopologicalSpace G] [IsTopologicalGroup G]
variable [CompactSpace G] [T2Space G] [TotallyDisconnectedSpace G]
abbrev relationPiFiltration (ν : Fin r → ℕ) (N : ℕ) :
    Submodule (ZMod p) (Fin r → ModPCompletedGroupAlgebra p G)
ClassFieldTower.ProP.foxPiFiltration
Source context 10 commands

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

namespace ClassFieldTower.ProP
open CompletedGroupAlgebra
open FoxDifferential
open ProCGroups
noncomputable section
universe u
variable {p d r : ℕ} [Fact p.Prime]
variable {sourceData :
  FreeProC.EpimorphicallyFreeProCGroupOnConvergingSetData.{u, u}
    (FiniteGroupClass.pGroup p)}
variable {G : Type u} [Group G] [TopologicalSpace G] [IsTopologicalGroup G]
variable [CompactSpace G] [T2Space G] [TotallyDisconnectedSpace G]
abbrev foxPiFiltration (N : ℕ) :
    Submodule (ZMod p) (Fin d → ModPCompletedGroupAlgebra p G)
ClassFieldTower.ProP.presentationModPRelationMatrixFin
Source context 10 commands

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

namespace ClassFieldTower.ProP
open CompletedGroupAlgebra
open FoxDifferential
open ProCGroups
noncomputable section
universe u
variable {p d r : ℕ} [Fact p.Prime]
variable {sourceData :
  FreeProC.EpimorphicallyFreeProCGroupOnConvergingSetData.{u, u}
    (FiniteGroupClass.pGroup p)}
variable {G : Type u} [Group G] [TopologicalSpace G] [IsTopologicalGroup G]
variable [CompactSpace G] [T2Space G] [TotallyDisconnectedSpace G]
def presentationModPRelationMatrixFin
    (P : FiniteProPPresentation p d r sourceData G) :
    (Fin r → ModPCompletedGroupAlgebra p G) →ₗ[ZMod p]
      (Fin d → ModPCompletedGroupAlgebra p G)
ClassFieldTower.ProP.presentationModPFoxBoundaryFin
Source context 10 commands

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

namespace ClassFieldTower.ProP
open CompletedGroupAlgebra
open FoxDifferential
open ProCGroups
noncomputable section
universe u
variable {p d r : ℕ} [Fact p.Prime]
variable {sourceData :
  FreeProC.EpimorphicallyFreeProCGroupOnConvergingSetData.{u, u}
    (FiniteGroupClass.pGroup p)}
variable {G : Type u} [Group G] [TopologicalSpace G] [IsTopologicalGroup G]
variable [CompactSpace G] [T2Space G] [TotallyDisconnectedSpace G]
def presentationModPFoxBoundaryFin
    (P : FiniteProPPresentation p d r sourceData G) :
    (Fin d → ModPCompletedGroupAlgebra p G) →ₗ[ZMod p]
      ModPCompletedGroupAlgebra p G
ClassFieldTower.ProP.relationMatrixFin_mem_foxPiFiltration
Source context 10 commands

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

namespace ClassFieldTower.ProP
open CompletedGroupAlgebra
open FoxDifferential
open ProCGroups
noncomputable section
universe u
variable {p d r : ℕ} [Fact p.Prime]
variable {sourceData :
  FreeProC.EpimorphicallyFreeProCGroupOnConvergingSetData.{u, u}
    (FiniteGroupClass.pGroup p)}
variable {G : Type u} [Group G] [TopologicalSpace G] [IsTopologicalGroup G]
variable [CompactSpace G] [T2Space G] [TotallyDisconnectedSpace G]
theorem relationMatrixFin_mem_foxPiFiltration
    (P : FiniteProPPresentation p d r sourceData G)
    (ν : Fin r → ℕ)
    (hν : ∀ j, P.RelatorZassenhausDepthAtLeast (ν j) j)
    (N : ℕ) :
    relationPiFiltration (p := p) (G := G) ν N ≤
      (foxPiFiltration (p := p) (G := G) (d := d) N).comap
        (presentationModPRelationMatrixFin P)
ClassFieldTower.ProP.foxBoundaryFin_mem_truncation
Source context 10 commands

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

namespace ClassFieldTower.ProP
open CompletedGroupAlgebra
open FoxDifferential
open ProCGroups
noncomputable section
universe u
variable {p d r : ℕ} [Fact p.Prime]
variable {sourceData :
  FreeProC.EpimorphicallyFreeProCGroupOnConvergingSetData.{u, u}
    (FiniteGroupClass.pGroup p)}
variable {G : Type u} [Group G] [TopologicalSpace G] [IsTopologicalGroup G]
variable [CompactSpace G] [T2Space G] [TotallyDisconnectedSpace G]
theorem foxBoundaryFin_mem_truncation
    (P : FiniteProPPresentation p d r sourceData G)
    (N : ℕ) :
    foxPiFiltration (p := p) (G := G) (d := d) N ≤
      (shiftedClosedAugmentationSubmodule (p := p) (G := G) N 0).comap
        (presentationModPFoxBoundaryFin P)
ClassFieldTower.ProP.presentationModPTruncatedRelationMap

The relation matrix induced on the shifted truncation quotients.

Source context 10 commands

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

namespace ClassFieldTower.ProP
open CompletedGroupAlgebra
open FoxDifferential
open ProCGroups
noncomputable section
universe u
variable {p d r : ℕ} [Fact p.Prime]
variable {sourceData :
  FreeProC.EpimorphicallyFreeProCGroupOnConvergingSetData.{u, u}
    (FiniteGroupClass.pGroup p)}
variable {G : Type u} [Group G] [TopologicalSpace G] [IsTopologicalGroup G]
variable [CompactSpace G] [T2Space G] [TotallyDisconnectedSpace G]
def presentationModPTruncatedRelationMap
    (P : FiniteProPPresentation p d r sourceData G)
    (ν : Fin r → ℕ)
    (hν : ∀ j, P.RelatorZassenhausDepthAtLeast (ν j) j)
    (N : ℕ) :
    PresentationModPTruncatedRelationSource (p := p) (G := G) ν N →ₗ[ZMod p]
      PresentationModPTruncatedFoxCoordinates (p := p) (d := d) (G := G) N
ClassFieldTower.ProP.presentationModPTruncatedFoxBoundary

The Fox boundary induced on the shifted truncation quotients.

Source context 10 commands

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

namespace ClassFieldTower.ProP
open CompletedGroupAlgebra
open FoxDifferential
open ProCGroups
noncomputable section
universe u
variable {p d r : ℕ} [Fact p.Prime]
variable {sourceData :
  FreeProC.EpimorphicallyFreeProCGroupOnConvergingSetData.{u, u}
    (FiniteGroupClass.pGroup p)}
variable {G : Type u} [Group G] [TopologicalSpace G] [IsTopologicalGroup G]
variable [CompactSpace G] [T2Space G] [TotallyDisconnectedSpace G]
def presentationModPTruncatedFoxBoundary
    (P : FiniteProPPresentation p d r sourceData G) (N : ℕ) :
    PresentationModPTruncatedFoxCoordinates (p := p) (d := d) (G := G) N →ₗ[ZMod p]
      ShiftedAugmentationTruncation (p := p) (G := G) N 0
ClassFieldTower.ProP.presentationModPTruncatedRelationMap_mk
Source context 10 commands

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

namespace ClassFieldTower.ProP
open CompletedGroupAlgebra
open FoxDifferential
open ProCGroups
noncomputable section
universe u
variable {p d r : ℕ} [Fact p.Prime]
variable {sourceData :
  FreeProC.EpimorphicallyFreeProCGroupOnConvergingSetData.{u, u}
    (FiniteGroupClass.pGroup p)}
variable {G : Type u} [Group G] [TopologicalSpace G] [IsTopologicalGroup G]
variable [CompactSpace G] [T2Space G] [TotallyDisconnectedSpace G]
theorem presentationModPTruncatedRelationMap_mk
    (P : FiniteProPPresentation p d r sourceData G)
    (ν : Fin r → ℕ)
    (hν : ∀ j, P.RelatorZassenhausDepthAtLeast (ν j) j)
    (N : ℕ) (a : Fin r → ModPCompletedGroupAlgebra p G) :
    presentationModPTruncatedRelationMap P ν hν N
        (fun j ↦ Submodule.Quotient.mk (a j)) =
      fun i ↦ Submodule.Quotient.mk
        ((presentationModPRelationMatrix P a) (ULift.up i)) := by
  let ps := relationTruncationFamily (p := p) (G := G) ν N
  have hs :
      (Submodule.quotientPi ps).symm.toLinearMap
          (fun j ↦ Submodule.Quotient.mk (a j)) =
        Submodule.Quotient.mk a := by
    change (Submodule.quotientPi ps).symm
        (fun j ↦ Submodule.Quotient.mk (a j)) = _
    rw [show (fun j ↦ Submodule.Quotient.mk (a j)) =
        (Submodule.quotientPi ps) (Submodule.Quotient.mk a) by rfl]
    exact (Submodule.quotientPi ps).symm_apply_apply _
  rw [presentationModPTruncatedRelationMap]
  simp only [LinearMap.comp_apply]
  rw [hs]
  rfl
ClassFieldTower.ProP.presentationModPTruncatedFoxBoundary_mk
Source context 10 commands

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

namespace ClassFieldTower.ProP
open CompletedGroupAlgebra
open FoxDifferential
open ProCGroups
noncomputable section
universe u
variable {p d r : ℕ} [Fact p.Prime]
variable {sourceData :
  FreeProC.EpimorphicallyFreeProCGroupOnConvergingSetData.{u, u}
    (FiniteGroupClass.pGroup p)}
variable {G : Type u} [Group G] [TopologicalSpace G] [IsTopologicalGroup G]
variable [CompactSpace G] [T2Space G] [TotallyDisconnectedSpace G]
theorem presentationModPTruncatedFoxBoundary_mk
    (P : FiniteProPPresentation p d r sourceData G)
    (N : ℕ) (v : Fin d → ModPCompletedGroupAlgebra p G) :
    presentationModPTruncatedFoxBoundary P N
        (fun i ↦ Submodule.Quotient.mk (v i)) =
      Submodule.Quotient.mk
        (presentationModPFoxBoundary P
          ((presentationModPFoxCoordinateFinEquiv
            (p := p) (d := d) (G := G)) v)) := by
  let pt := foxTruncationFamily (p := p) (G := G) (d := d) N
  have ht :
      (Submodule.quotientPi pt).symm.toLinearMap
          (fun i ↦ Submodule.Quotient.mk (v i)) =
        Submodule.Quotient.mk v := by
    change (Submodule.quotientPi pt).symm
        (fun i ↦ Submodule.Quotient.mk (v i)) = _
    rw [show (fun i ↦ Submodule.Quotient.mk (v i)) =
        (Submodule.quotientPi pt) (Submodule.Quotient.mk v) by rfl]
    exact (Submodule.quotientPi pt).symm_apply_apply _
  rw [presentationModPTruncatedFoxBoundary]
  simp only [LinearMap.comp_apply]
  rw [ht]
  rfl
Source context 10 commands

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

namespace ClassFieldTower.ProP
open CompletedGroupAlgebra
open FoxDifferential
open ProCGroups
noncomputable section
universe u
variable {p d r : ℕ} [Fact p.Prime]
variable {sourceData :
  FreeProC.EpimorphicallyFreeProCGroupOnConvergingSetData.{u, u}
    (FiniteGroupClass.pGroup p)}
variable {G : Type u} [Group G] [TopologicalSpace G] [IsTopologicalGroup G]
variable [CompactSpace G] [T2Space G] [TotallyDisconnectedSpace G]
instance : AddCommGroup (ZMod p)
Source context 11 commands

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

namespace ClassFieldTower.ProP
open CompletedGroupAlgebra
open FoxDifferential
open ProCGroups
noncomputable section
universe u
variable {p d r : ℕ} [Fact p.Prime]
variable {sourceData :
  FreeProC.EpimorphicallyFreeProCGroupOnConvergingSetData.{u, u}
    (FiniteGroupClass.pGroup p)}
variable {G : Type u} [Group G] [TopologicalSpace G] [IsTopologicalGroup G]
variable [CompactSpace G] [T2Space G] [TotallyDisconnectedSpace G]
local instance : AddCommGroup (ZMod p) :=
  (ZMod.instField p).toDivisionRing.toAddCommGroup
instance : Module (ZMod p) (ZMod p)
ClassFieldTower.ProP.presentationModPAugmentationLinearMap
Source context 12 commands

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

namespace ClassFieldTower.ProP
open CompletedGroupAlgebra
open FoxDifferential
open ProCGroups
noncomputable section
universe u
variable {p d r : ℕ} [Fact p.Prime]
variable {sourceData :
  FreeProC.EpimorphicallyFreeProCGroupOnConvergingSetData.{u, u}
    (FiniteGroupClass.pGroup p)}
variable {G : Type u} [Group G] [TopologicalSpace G] [IsTopologicalGroup G]
variable [CompactSpace G] [T2Space G] [TotallyDisconnectedSpace G]
local instance : AddCommGroup (ZMod p) :=
  (ZMod.instField p).toDivisionRing.toAddCommGroup
local instance : Module (ZMod p) (ZMod p) := Semiring.toModule
def presentationModPAugmentationLinearMap :
    ModPCompletedGroupAlgebra p G →ₗ[ZMod p] ZMod p where
  toFun := completedGroupAlgebraCanonicalAugmentationInClass
    (R := ZMod p) (G := G) (FiniteGroupClass.pGroup p)
  map_add' x y := by simp
  map_smul' c x := by
    change completedGroupAlgebraCanonicalAugmentationInClass
        (R := ZMod p) (G := G) (FiniteGroupClass.pGroup p) (c • x) =
      c • completedGroupAlgebraCanonicalAugmentationInClass
        (R := ZMod p) (G := G) (FiniteGroupClass.pGroup p) x
    simp [Algebra.smul_def]
ClassFieldTower.ProP.shiftedTruncation_le_augmentation_ker
Source context 13 commands

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

namespace ClassFieldTower.ProP
open CompletedGroupAlgebra
open FoxDifferential
open ProCGroups
noncomputable section
universe u
variable {p d r : ℕ} [Fact p.Prime]
variable {sourceData :
  FreeProC.EpimorphicallyFreeProCGroupOnConvergingSetData.{u, u}
    (FiniteGroupClass.pGroup p)}
variable {G : Type u} [Group G] [TopologicalSpace G] [IsTopologicalGroup G]
variable [CompactSpace G] [T2Space G] [TotallyDisconnectedSpace G]
local instance : AddCommGroup (ZMod p) :=
  (ZMod.instField p).toDivisionRing.toAddCommGroup
local instance : Module (ZMod p) (ZMod p) := Semiring.toModule
omit [CompactSpace G] [T2Space G] [TotallyDisconnectedSpace G] in
theorem shiftedTruncation_le_augmentation_ker (N : ℕ) :
    shiftedClosedAugmentationSubmodule (p := p) (G := G) N 0 ≤
      (presentationModPAugmentationLinearMap (p := p) (G := G)).ker
ClassFieldTower.ProP.presentationModPTruncatedAugmentation

The canonical augmentation induced on the unshifted truncation.

Source context 12 commands

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

namespace ClassFieldTower.ProP
open CompletedGroupAlgebra
open FoxDifferential
open ProCGroups
noncomputable section
universe u
variable {p d r : ℕ} [Fact p.Prime]
variable {sourceData :
  FreeProC.EpimorphicallyFreeProCGroupOnConvergingSetData.{u, u}
    (FiniteGroupClass.pGroup p)}
variable {G : Type u} [Group G] [TopologicalSpace G] [IsTopologicalGroup G]
variable [CompactSpace G] [T2Space G] [TotallyDisconnectedSpace G]
local instance : AddCommGroup (ZMod p) :=
  (ZMod.instField p).toDivisionRing.toAddCommGroup
local instance : Module (ZMod p) (ZMod p) := Semiring.toModule
def presentationModPTruncatedAugmentation (N : ℕ) :
    ShiftedAugmentationTruncation (p := p) (G := G) N 0 →ₗ[ZMod p] ZMod p
ClassFieldTower.ProP.presentationModPTruncatedAugmentation_mk
Source context 13 commands

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

namespace ClassFieldTower.ProP
open CompletedGroupAlgebra
open FoxDifferential
open ProCGroups
noncomputable section
universe u
variable {p d r : ℕ} [Fact p.Prime]
variable {sourceData :
  FreeProC.EpimorphicallyFreeProCGroupOnConvergingSetData.{u, u}
    (FiniteGroupClass.pGroup p)}
variable {G : Type u} [Group G] [TopologicalSpace G] [IsTopologicalGroup G]
variable [CompactSpace G] [T2Space G] [TotallyDisconnectedSpace G]
local instance : AddCommGroup (ZMod p) :=
  (ZMod.instField p).toDivisionRing.toAddCommGroup
local instance : Module (ZMod p) (ZMod p) := Semiring.toModule
omit [CompactSpace G] [T2Space G] [TotallyDisconnectedSpace G] in
theorem presentationModPTruncatedAugmentation_mk
    (N : ℕ) (x : ModPCompletedGroupAlgebra p G) :
    presentationModPTruncatedAugmentation (p := p) (G := G) N
        (Submodule.Quotient.mk x) =
      completedGroupAlgebraCanonicalAugmentationInClass
        (R := ZMod p) (G := G) (FiniteGroupClass.pGroup p) x
ClassFieldTower.ProP.presentationModPTruncatedRelationSource_mk_surjective
Source context 13 commands

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

namespace ClassFieldTower.ProP
open CompletedGroupAlgebra
open FoxDifferential
open ProCGroups
noncomputable section
universe u
variable {p d r : ℕ} [Fact p.Prime]
variable {sourceData :
  FreeProC.EpimorphicallyFreeProCGroupOnConvergingSetData.{u, u}
    (FiniteGroupClass.pGroup p)}
variable {G : Type u} [Group G] [TopologicalSpace G] [IsTopologicalGroup G]
variable [CompactSpace G] [T2Space G] [TotallyDisconnectedSpace G]
local instance : AddCommGroup (ZMod p) :=
  (ZMod.instField p).toDivisionRing.toAddCommGroup
local instance : Module (ZMod p) (ZMod p) := Semiring.toModule
omit [CompactSpace G] [T2Space G] [TotallyDisconnectedSpace G] in
theorem presentationModPTruncatedRelationSource_mk_surjective
    (ν : Fin r → ℕ) (N : ℕ) :
    Function.Surjective
      (fun a : Fin r → ModPCompletedGroupAlgebra p G ↦
        (fun j ↦ Submodule.Quotient.mk (a j) :
          PresentationModPTruncatedRelationSource (p := p) (G := G) ν N)) := by
  classical
  intro x
  choose a ha using fun j ↦
    (shiftedClosedAugmentationSubmodule
      (p := p) (G := G) N (ν j)).mkQ_surjective (x j)
  refine ⟨a, ?_⟩
  funext j
  exact ha j
ClassFieldTower.ProP.presentationModPTruncatedFoxCoordinates_mk_surjective
Source context 13 commands

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

namespace ClassFieldTower.ProP
open CompletedGroupAlgebra
open FoxDifferential
open ProCGroups
noncomputable section
universe u
variable {p d r : ℕ} [Fact p.Prime]
variable {sourceData :
  FreeProC.EpimorphicallyFreeProCGroupOnConvergingSetData.{u, u}
    (FiniteGroupClass.pGroup p)}
variable {G : Type u} [Group G] [TopologicalSpace G] [IsTopologicalGroup G]
variable [CompactSpace G] [T2Space G] [TotallyDisconnectedSpace G]
local instance : AddCommGroup (ZMod p) :=
  (ZMod.instField p).toDivisionRing.toAddCommGroup
local instance : Module (ZMod p) (ZMod p) := Semiring.toModule
omit [CompactSpace G] [T2Space G] [TotallyDisconnectedSpace G] in
theorem presentationModPTruncatedFoxCoordinates_mk_surjective (N : ℕ) :
    Function.Surjective
      (fun v : Fin d → ModPCompletedGroupAlgebra p G ↦
        (fun i ↦ Submodule.Quotient.mk (v i) :
          PresentationModPTruncatedFoxCoordinates
            (p := p) (d := d) (G := G) N)) := by
  classical
  intro x
  choose v hv using fun i ↦
    (shiftedClosedAugmentationSubmodule
      (p := p) (G := G) N 1).mkQ_surjective (x i)
  refine ⟨v, ?_⟩
  funext i
  exact hv i
ClassFieldTower.ProP.presentationModPTruncatedFoxBoundary_comp_relationMap

The induced relation map is killed by the induced Fox boundary.

Source context 12 commands

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

namespace ClassFieldTower.ProP
open CompletedGroupAlgebra
open FoxDifferential
open ProCGroups
noncomputable section
universe u
variable {p d r : ℕ} [Fact p.Prime]
variable {sourceData :
  FreeProC.EpimorphicallyFreeProCGroupOnConvergingSetData.{u, u}
    (FiniteGroupClass.pGroup p)}
variable {G : Type u} [Group G] [TopologicalSpace G] [IsTopologicalGroup G]
variable [CompactSpace G] [T2Space G] [TotallyDisconnectedSpace G]
local instance : AddCommGroup (ZMod p) :=
  (ZMod.instField p).toDivisionRing.toAddCommGroup
local instance : Module (ZMod p) (ZMod p) := Semiring.toModule
theorem presentationModPTruncatedFoxBoundary_comp_relationMap
    (P : FiniteProPPresentation p d r sourceData G)
    (ν : Fin r → ℕ)
    (hν : ∀ j, P.RelatorZassenhausDepthAtLeast (ν j) j)
    (N : ℕ) :
    (presentationModPTruncatedFoxBoundary P N).comp
        (presentationModPTruncatedRelationMap P ν hν N) = 0
ClassFieldTower.ProP.presentationModPTruncatedAugmentation_comp_foxBoundary

The induced augmentation kills the induced Fox boundary.

Source context 12 commands

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

namespace ClassFieldTower.ProP
open CompletedGroupAlgebra
open FoxDifferential
open ProCGroups
noncomputable section
universe u
variable {p d r : ℕ} [Fact p.Prime]
variable {sourceData :
  FreeProC.EpimorphicallyFreeProCGroupOnConvergingSetData.{u, u}
    (FiniteGroupClass.pGroup p)}
variable {G : Type u} [Group G] [TopologicalSpace G] [IsTopologicalGroup G]
variable [CompactSpace G] [T2Space G] [TotallyDisconnectedSpace G]
local instance : AddCommGroup (ZMod p) :=
  (ZMod.instField p).toDivisionRing.toAddCommGroup
local instance : Module (ZMod p) (ZMod p) := Semiring.toModule
theorem presentationModPTruncatedAugmentation_comp_foxBoundary
    (P : FiniteProPPresentation p d r sourceData G) (N : ℕ) :
    (presentationModPTruncatedAugmentation (p := p) (G := G) N).comp
        (presentationModPTruncatedFoxBoundary P N) = 0