OAI/Geometry/HyperbolicGroups/BoundaryIndex.lean
6 declarations, 0 contain sorry, 0 declared as axioms
- def
OAI.HyperbolicObstruction.PictureSwitch.boundaryIndexline 18Source 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 := … - lemma
OAI.HyperbolicObstruction.PictureSwitch.boundaryIndex_getline 22 - lemma
OAI.HyperbolicObstruction.PictureSwitch.boundaryIndex_labelline 29 - lemma
OAI.HyperbolicObstruction.PictureSwitch.boundaryIndex_injline 39 - lemma
OAI.HyperbolicObstruction.PictureSwitch.boundaryIndex_commuteline 51 - theorem
OAI.HyperbolicObstruction.PictureSwitch.indexedFaceMap_existsline 67Source 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