OAI/Geometry/HyperbolicGroups/PictureRootSeparator.lean
1 declarations, 0 contain sorry, 0 declared as axioms
- theorem
OAI.HyperbolicObstruction.PictureSwitch.PictureMap.root_path_weighted_separatorline 26Source documentation
A dual centroid gives a separator consisting of the actual root paths to one face. No radius hypothesis is imposed; a later annulus argument counts only the portion between two selected BFS levels.
theorem root_path_weighted_separator (hG : M.GenusZero) (hspan : SameCycle.setoid M.vertex ⊔ SameCycle.setoid q = ⊤) (hboundary : cycles (M.vertex*q) = 1) (root : M.GraphVertex) (weight : M.GraphVertex → ℝ) (hw : ∀ v, 0 ≤ weight v) : ∃ f : M.dual.GraphVertex, ∀ U : Finset M.GraphVertex, Disjoint U (treePathHull _ (M.subpairing_isTree hG q hq hspan hboundary) root (M.faceCorners f)) → (M.underlyingGraph.induce (U : Set M.GraphVertex)).Preconnected → 2 * ∑ v ∈ U, weight v ≤ ∑ v : M.GraphVertex, weight v := by …