OAI/Topology/ArtinGroups/ParabolicIntersections/ConnectedMinima.lean
8 declarations, 0 contain sorry, 0 declared as axioms
Lowering paths across tied heights
This is the finite-path argument of §6.5 of paper 082-03. The local hypotheses are precisely the connected descending neighborhoods and the compatibility across tied adjacent vertices. They are not installed as published assumptions; their verification for the relative harmonic height is a separate part of that paper's proof.
- def
OAI.HarmonicArtin.ParabolicIntersections.PathWithinline 24Source documentation
Paths all of whose edges and vertices lie in a specified region. For the reflexive path the endpoint condition is supplied separately.
def PathWithin (p : V → Prop) (a b : V) : Prop := …
- theorem
OAI.HarmonicArtin.ParabolicIntersections.path_monoline 27 - structure
OAI.HarmonicArtin.ParabolicIntersections.LocalDescentline 36Source documentation
Descending neighbors at one vertex lie in one strict-sublevel component; a tied edge carries that component to the other vertex.
structure LocalDescent : Prop where …
- theorem
OAI.HarmonicArtin.ParabolicIntersections.lower_pathline 48Source documentation
Remove all occurrences of one maximal height in a finite path. The invariant also covers a whole segment of tied vertices.
theorem lower_path (D : LocalDescent adj height) (h : H) {a b : V} (ha : height a < h) (hb : height b < h) (p : PathWithin adj (fun v => height v ≤ h) a b) : PathWithin adj (fun v => height v < h) a b := by …Mentions: OAI.HarmonicArtin.ParabolicIntersections.LocalDescent, OAI.HarmonicArtin.ParabolicIntersections.PathWithin
- theorem
OAI.HarmonicArtin.ParabolicIntersections.bounded_pathline 82 - theorem
OAI.HarmonicArtin.ParabolicIntersections.strictly_bounded_pathline 96 - theorem
OAI.HarmonicArtin.ParabolicIntersections.sublevel_pathline 115Source documentation
Every sublevel of a well-founded height with the two local descent properties contains a path between any of its vertices that were connected in the original graph.
theorem sublevel_path (D : LocalDescent adj height) (wf : WellFounded ((· < ·) : H → H → Prop)) (c : H) {a b : V} (ha : height a ≤ c) (hb : height b ≤ c) (p : Relation.ReflTransGen adj a b) : PathWithin adj (fun v => height v ≤ c) a b := by …Mentions: OAI.HarmonicArtin.ParabolicIntersections.LocalDescent, OAI.HarmonicArtin.ParabolicIntersections.PathWithin
- theorem
OAI.HarmonicArtin.ParabolicIntersections.minimum_pathline 133Source documentation
The minimum-height vertices in a connected graph form a connected subgraph. This is the path-lowering conclusion used in §6.5.
theorem minimum_path (D : LocalDescent adj height) (wf : WellFounded ((· < ·) : H → H → Prop)) {a b : V} (ha : ∀ v, height a ≤ height v) (hb : ∀ v, height b ≤ height v) (p : Relation.ReflTransGen adj a b) : PathWithin adj (fun v => ∀ w, height v ≤ height w) a b := by …Mentions: OAI.HarmonicArtin.ParabolicIntersections.LocalDescent, OAI.HarmonicArtin.ParabolicIntersections.PathWithin