Module

Boundary.lean

Nyll.ProCGroups.FoxDifferential.Completed.FiniteStage.CoeffMap.Boundary
2 declarations indexed from sourceView source ↗

Fox differential: completed — finite stage — coeff map — boundary

The principal declarations in this module are:

  • foxAlgebraicStageFoxBoundary_coeffMap

Coefficient reduction commutes with the finite-stage Fox boundary map.

  • foxAlgebraicStageBoundaryCycleSubmodule_coeffMap_mem

A vector is a boundary cycle after coefficient reduction whenever it was one before reduction.

Declarations

FoxDifferential.foxAlgebraicStageFoxBoundary_coeffMap

Coefficient reduction commutes with the finite-stage Fox boundary map.

Source context 13 commands

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

namespace FoxDifferential
noncomputable section
open scoped BigOperators
open ProCGroups.InverseSystems
open ProCGroups.ProC
universe u v
variable (ℓ : ℕ) [Fact (0 < ℓ)]
variable {G : Type u} [Group G] [TopologicalSpace G] [IsTopologicalGroup G]
variable {H : Type v} [Group H] [TopologicalSpace H] [IsTopologicalGroup H]
variable {X : Type u} [DecidableEq X]
variable (N : Subgroup (FreeGroup X)) [N.Normal] (n : ℕ)
variable {n₀ m₀ : ℕ} [Fact (0 < n₀)] [Fact (0 < m₀)]
omit [DecidableEq X] [Fact (0 < n₀)] [Fact (0 < m₀)] in
theorem foxAlgebraicStageFoxBoundary_coeffMap
    [Fintype X]
    (N : Subgroup (FreeGroup X)) [N.Normal] (hnm : n₀ ∣ m₀)
    (v : foxAlgebraicStageCoordinateVector (X := X) N m₀) :
    foxAlgebraicStageTargetGroupAlgebraCoeffMap (X := X) N hnm
        (foxAlgebraicStageFoxBoundary (X := X) N m₀ v) =
      foxAlgebraicStageFoxBoundary (X := X) N n₀
        (fun i : X =>
          foxAlgebraicStageTargetGroupAlgebraCoeffMap (X := X) N hnm (v i)) := by
  rw [foxAlgebraicStageFoxBoundary_apply, foxAlgebraicStageFoxBoundary_apply]
  simp only [QuotientGroup.mk'_apply, MonoidAlgebra.of_apply, map_sum, map_mul, map_sub,
  foxAlgebraicStageTargetGroupAlgebraCoeffMap_single_apply, map_one]
FoxDifferential.foxAlgebraicStageBoundaryCycleSubmodule_coeffMap_mem

A vector is a boundary cycle after coefficient reduction whenever it was one before reduction.

Source context 13 commands

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

namespace FoxDifferential
noncomputable section
open scoped BigOperators
open ProCGroups.InverseSystems
open ProCGroups.ProC
universe u v
variable (ℓ : ℕ) [Fact (0 < ℓ)]
variable {G : Type u} [Group G] [TopologicalSpace G] [IsTopologicalGroup G]
variable {H : Type v} [Group H] [TopologicalSpace H] [IsTopologicalGroup H]
variable {X : Type u} [DecidableEq X]
variable (N : Subgroup (FreeGroup X)) [N.Normal] (n : ℕ)
variable {n₀ m₀ : ℕ} [Fact (0 < n₀)] [Fact (0 < m₀)]
omit [DecidableEq X] [Fact (0 < n₀)] [Fact (0 < m₀)] in
theorem foxAlgebraicStageBoundaryCycleSubmodule_coeffMap_mem
    [Fintype X]
    (N : Subgroup (FreeGroup X)) [N.Normal] (hnm : n₀ ∣ m₀)
    {v : foxAlgebraicStageCoordinateVector (X := X) N m₀}
    (hv : v ∈ foxAlgebraicStageBoundaryCycleSubmodule (X := X) N m₀) :
    (fun i : X =>
        foxAlgebraicStageTargetGroupAlgebraCoeffMap (X := X) N hnm (v i)) ∈
      foxAlgebraicStageBoundaryCycleSubmodule (X := X) N n₀ := by
  rw [mem_foxAlgebraicStageBoundaryCycleSubmodule]
  rw [← foxAlgebraicStageFoxBoundary_coeffMap (X := X) N hnm v]
  rw [mem_foxAlgebraicStageBoundaryCycleSubmodule] at hv
  rw [hv]
  exact map_zero _