Module

BoundaryCycles.lean

Nyll.ProCGroups.FoxDifferential.Completed.FiniteStage.CoeffMap.BoundaryCycles
7 declarations indexed from sourceView source ↗

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

The principal declarations in this module are:

  • foxAlgebraicStageSemidirectCoeffMap_left

The left component of finite-stage semidirect coefficient reduction is obtained by reducing each coordinate coefficient.

  • foxAlgebraicStageSemidirectCoeffMap_right

The right component of finite-stage semidirect coefficient reduction is unchanged.

  • foxAlgebraicStageSemidirectCoeffMap_rfl

Coefficient reduction is the identity on finite-stage semidirect targets when the modulus is unchanged.

  • foxAlgebraicStageSemidirectCoeffMap_comp

Coefficient reductions compose on finite-stage semidirect targets.

Declarations

FoxDifferential.foxAlgebraicStageSemidirectCoeffMap_left

The left component of finite-stage semidirect coefficient reduction is obtained by reducing each coordinate coefficient.

Source context 12 commands

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

namespace FoxDifferential
noncomputable section
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 foxAlgebraicStageSemidirectCoeffMap_left
    (N : Subgroup (FreeGroup X)) [N.Normal] (hnm : n₀ ∣ m₀)
    (y : FoxAlgebraicStageSemidirect (X := X) N m₀) :
    (foxAlgebraicStageSemidirectCoeffMap (X := X) N hnm y).left =
      fun i : X => foxAlgebraicStageTargetGroupAlgebraCoeffMap (X := X) N hnm (y.left i) :=
  rfl
FoxDifferential.foxAlgebraicStageSemidirectCoeffMap_right

The right component of finite-stage semidirect coefficient reduction is unchanged.

Source context 12 commands

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

namespace FoxDifferential
noncomputable section
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 foxAlgebraicStageSemidirectCoeffMap_right
    (N : Subgroup (FreeGroup X)) [N.Normal] (hnm : n₀ ∣ m₀)
    (y : FoxAlgebraicStageSemidirect (X := X) N m₀) :
    (foxAlgebraicStageSemidirectCoeffMap (X := X) N hnm y).right = y.right
FoxDifferential.foxAlgebraicStageSemidirectCoeffMap_rfl

Coefficient reduction is the identity on finite-stage semidirect targets when the modulus is unchanged.

Source context 12 commands

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

namespace FoxDifferential
noncomputable section
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 [Fact (0 < m₀)] [DecidableEq X] [Fact (0 < n₀)] in
theorem foxAlgebraicStageSemidirectCoeffMap_rfl
    (N : Subgroup (FreeGroup X)) [N.Normal] :
    foxAlgebraicStageSemidirectCoeffMap
        (X := X) (n₀ := n₀) (m₀ := n₀) N dvd_rfl =
      MonoidHom.id (FoxAlgebraicStageSemidirect (X := X) N n₀)
FoxDifferential.foxAlgebraicStageSemidirectCoeffMap_comp

Coefficient reductions compose on finite-stage semidirect targets.

Source context 12 commands

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

namespace FoxDifferential
noncomputable section
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 foxAlgebraicStageSemidirectCoeffMap_comp
    {k₀ : ℕ}
    (N : Subgroup (FreeGroup X)) [N.Normal]
    (hnm : n₀ ∣ m₀) (hmk : m₀ ∣ k₀) :
    (foxAlgebraicStageSemidirectCoeffMap (X := X) N hnm).comp
        (foxAlgebraicStageSemidirectCoeffMap (X := X) N hmk) =
      foxAlgebraicStageSemidirectCoeffMap (X := X) N (dvd_trans hnm hmk)
FoxDifferential.foxAlgebraicStageSemidirectCoeffMap_mem_boundaryCycleSet

Coefficient reduction carries finite semidirect boundary cycles to finite semidirect boundary cycles.

Source context 12 commands

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

namespace FoxDifferential
noncomputable section
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 foxAlgebraicStageSemidirectCoeffMap_mem_boundaryCycleSet
    [Fintype X]
    (N : Subgroup (FreeGroup X)) [N.Normal] (hnm : n₀ ∣ m₀)
    {y : FoxAlgebraicStageSemidirect (X := X) N m₀}
    (hy : y ∈ foxAlgebraicStageSemidirectBoundaryCycleSet (X := X) N m₀) :
    foxAlgebraicStageSemidirectCoeffMap (X := X) N hnm y ∈
      foxAlgebraicStageSemidirectBoundaryCycleSet (X := X) N n₀
FoxDifferential.foxAlgebraicStageSemidirectCoeffMap_kernelWordPoint

Coefficient reduction sends the finite semidirect kernel-word point at modulus \(m\) to the corresponding point at modulus \(n\).

Source context 12 commands

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

namespace FoxDifferential
noncomputable section
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 [Fact (0 < n₀)] [Fact (0 < m₀)] in
theorem foxAlgebraicStageSemidirectCoeffMap_kernelWordPoint
    (N : Subgroup (FreeGroup X)) [N.Normal] (hnm : n₀ ∣ m₀)
    (w : FreeGroup X) :
    foxAlgebraicStageSemidirectCoeffMap (X := X) N hnm
        (foxAlgebraicStageSemidirectKernelWordPoint (X := X) N m₀ w) =
      foxAlgebraicStageSemidirectKernelWordPoint (X := X) N n₀ w
FoxDifferential.foxAlgebraicStageSemidirectCoeffMap_kernelWordDerivativeSet_subset

Coefficient reduction sends the finite semidirect kernel-word derivative set at modulus \(m\) into the corresponding set at modulus \(n\).

Source context 12 commands

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

namespace FoxDifferential
noncomputable section
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 [Fact (0 < n₀)] [Fact (0 < m₀)] in
theorem foxAlgebraicStageSemidirectCoeffMap_kernelWordDerivativeSet_subset
    (N : Subgroup (FreeGroup X)) [N.Normal] (hnm : n₀ ∣ m₀) :
    (fun y : FoxAlgebraicStageSemidirect (X := X) N m₀ =>
        foxAlgebraicStageSemidirectCoeffMap (X := X) N hnm y) ''
      foxAlgebraicStageSemidirectKernelWordDerivativeSet (X := X) N m₀ ⊆
        foxAlgebraicStageSemidirectKernelWordDerivativeSet (X := X) N n₀ := by
  intro y hy
  rcases hy with ⟨z, hz, rfl⟩
  rcases hz with ⟨w, hwN, hzw⟩
  refine ⟨w, hwN, ?_⟩
  rw [← hzw]
  exact (foxAlgebraicStageSemidirectCoeffMap_kernelWordPoint (X := X) N hnm w).symm