OAI/Geometry/HyperbolicGroups/BoundaryIndex.lean

GitHub source file

6 declarations, 0 contain sorry, 0 declared as axioms

  1. def OAI.HyperbolicObstruction.PictureSwitch.boundaryIndex line 18

    Source documentation

    A literal indexed match between two enumerated boundaries. Repeated edge letters are not quotiented: this map uses the unique side positions.

    def boundaryIndex (xs : List D) (ys : List S) (hlen : xs.length = ys.length)
        (x : D) (hx : x ∈ xs) : S :=
    …
  2. lemma OAI.HyperbolicObstruction.PictureSwitch.boundaryIndex_get line 22
  3. lemma OAI.HyperbolicObstruction.PictureSwitch.boundaryIndex_label line 29
  4. lemma OAI.HyperbolicObstruction.PictureSwitch.boundaryIndex_inj line 39
  5. lemma OAI.HyperbolicObstruction.PictureSwitch.boundaryIndex_commute line 51
  6. theorem OAI.HyperbolicObstruction.PictureSwitch.indexedFaceMap_exists line 67

    Source documentation

    Build a coherent index map by selecting one boundary match PER FACE, not independently per side. This is the coherence step between word van Kampen diagrams and actual cellular pictures.

    theorem indexedFaceMap_exists (f : Perm D) (t : Perm S) (label : D → L) (edge : S → L)
        (h : ∀ x : D, ∃ xs : List D, ∃ ys : List S,
          IsBoundary f xs ∧ x ∈ xs ∧ IsBoundary t ys ∧ xs.map label = ys.map edge) :
        ∃ j : D → S, IndexedFaceMap f t j ∧ ∀ x, edge (j x) = label x := by
    …

    Mentions: OAI.HyperbolicObstruction.PictureSwitch.IsBoundary, OAI.HyperbolicObstruction.PictureSwitch.IndexedFaceMap