OAI/Topology/CoarseAssembly/CocycleCircleMap.lean

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15 declarations, 0 contain sorry, 0 declared as axioms

The circle map of an integral Rips cocycle

On each finite component, barycentric interpolation of an integral edge cocycle defines a genuine continuous map to ℝ / ℤ. The local real lifts differ by the integral edge charge. This constructs the winding test in the manuscript, rather than assuming its topological extension.

  1. structure OAI.CoarseAssembly.Rips.IntegralCocycle line 26

    Source documentation

    Integral charges with the two identities required on a Rips simplex.

    structure IntegralCocycle (X : Type*) [PseudoMetricSpace X] (r : ℝ) where
    …
  2. theorem OAI.CoarseAssembly.Rips.IntegralCocycle.difference line 32
  3. theorem OAI.CoarseAssembly.Rips.Point.exists_positive line 39
  4. def OAI.CoarseAssembly.Rips.Point.supportVertex line 48
  5. theorem OAI.CoarseAssembly.Rips.Point.supportVertex_positive line 50
  6. theorem OAI.CoarseAssembly.Rips.Point.supportVertex_mem line 53
  7. def OAI.CoarseAssembly.Rips.IntegralCocycle.localAngle line 60

    Source documentation

    Local real lift based at a vertex of the supporting simplex.

    def IntegralCocycle.localAngle (c : IntegralCocycle X r) (x : X) (p : Point X r) : ℝ :=
    …

    Mentions: OAI.CoarseAssembly.Rips.IntegralCocycle, OAI.CoarseAssembly.Rips.Point

  8. theorem OAI.CoarseAssembly.Rips.IntegralCocycle.localAngle_continuous line 63
  9. theorem OAI.CoarseAssembly.Rips.Point.sum_weight line 68
  10. theorem OAI.CoarseAssembly.Rips.IntegralCocycle.localAngle_sub line 73

    Source documentation

    Changes of local lift are exactly the prescribed integral charges.

    theorem IntegralCocycle.localAngle_sub (c : IntegralCocycle X r) (p : Point X r)
        {x y : X} (hx : x ∈ p.weight.support) (hy : y ∈ p.weight.support) :
        c.localAngle x p - c.localAngle y p = (c.charge x y : ℝ) := by
    …

    Mentions: OAI.CoarseAssembly.Rips.IntegralCocycle, OAI.CoarseAssembly.Rips.Point

  11. theorem OAI.CoarseAssembly.Rips.IntegralCocycle.localAngle_coe_eq line 94
  12. def OAI.CoarseAssembly.Rips.IntegralCocycle.circleMap line 103

    Source documentation

    Barycentric interpolation of the cocycle, with values in the unit circle.

    def IntegralCocycle.circleMap (c : IntegralCocycle X r) (p : Point X r) :
        AddCircle (1 : ℝ) := c.localAngle p.supportVertex p

    Mentions: OAI.CoarseAssembly.Rips.IntegralCocycle, OAI.CoarseAssembly.Rips.Point

  13. theorem OAI.CoarseAssembly.Rips.IntegralCocycle.circleMap_eq line 106
  14. theorem OAI.CoarseAssembly.Rips.IntegralCocycle.circleMap_continuous line 111
  15. def OAI.CoarseAssembly.Rips.IntegralCocycle.toContinuousMap line 125