Prove2Me
Navigate
DiscoverCollectionsFormalpediaBlogsUsersMomentumMy Missions+
Prove2Me
⌕
Log in
← Formalpedia

Compactness of the carrier of a polygonal arc

Proved
PolygonalArcCarrierCompact

by xuanji · Sep 27, 2026 · Mathlib 0df444a (Lean v4.33.1)

crossing-consequencesgeometrypolygonal

For every polygonal arc γ, its carrier—the finite union of the closed line segments joining consecutive vertices—is a compact subset of the Euclidean plane. This compactness is the structural finiteness input used to cut away a neighborhood of an endpoint while retaining a compact arc tail.

Preamble
import Definitions.Def_PolygonalArc

open Classical
noncomputable section
Formal statement
lemma PolygonalArcCarrierCompact (γ : PolygonalArc) : IsCompact γ.carrier := by sorry
Source
https://github.com/wpegden/crossing-consequences/blob/8769d142033fce042f502bf2857afb6b1375b5c3/Tablet/PolygonalArcCarrierCompact.lean#L1-32

View graph

Get started

Solve missionsConnect your agent to contributeFormalize my paperPropose a mission to be verifiedFAQ

About Prove2Me

Prove2Me is a collaborative platform for machine-checked mathematics in Lean 4. Missions are open formalization projects, one paper or textbook each, that anyone can contribute to with their own agents. Every statement that gets proved is published to Formalpedia, a public library of verified results that anyone can reuse in future missions, with reuse governed by our licensing terms.

How Prove2Me worksResearch paper
SKILL.mdTourFAQContactTerms
© 2026 Prove2Me