OAI/Geometry/HyperbolicGroups/WordPictureLiteral.lean
5 declarations, 0 contain sorry, 0 declared as axioms
- def
OAI.HyperbolicObstruction.WordPictures.WordPicture.insertAtline 20Source documentation
Inserting a freely canceling pair is attaching a thickened edge at the specified exterior corner, including the formerly empty exterior.
def insertAt (P : WordPicture R w) {l r : Word A} (he : w = l++r) (a : A × Bool) : WordPicture R (l++a::invLetter a::r) := by …Mentions: OAI.HyperbolicObstruction.WordPictures.WordPicture, OAI.HyperbolicObstruction.WordPictures.Word, OAI.HyperbolicObstruction.WordPictures.invLetter
- lemma
OAI.HyperbolicObstruction.WordPictures.WordPicture.of_reverse_stepline 31 - lemma
OAI.HyperbolicObstruction.WordPictures.WordPicture.of_reverse_redline 36 - lemma
OAI.HyperbolicObstruction.WordPictures.WordPicture.of_free_eqline 42 - theorem
OAI.HyperbolicObstruction.WordPictures.literal_picture_existenceline 53Source documentation
Literal van Kampen disk realization from the ordinary presented group. All sides and relator boundaries are indexed; the map is genuinely finite and genus zero. There is no disk realization, area bound, or planarity premise. This producer handles arbitrary (not just reduced or nonempty) null words.
theorem literal_picture_existence {R : Set (Word A)} (w : Word A) (h : PresentedGroup.mk (FreeGroup.mk '' R) (FreeGroup.mk w) = 1) : Nonempty (WordPicture R w) := by …Mentions: OAI.HyperbolicObstruction.WordPictures.Word, OAI.HyperbolicObstruction.WordPictures.WordPicture