English

Random 0/1-polytopes expand rapidly

Combinatorics 2026-04-13 v1 Discrete Mathematics Probability

Abstract

A 0/1-polytope is the convex hull of a subset V{0,1}nV\subseteq \{0,1\}^n. A celebrated conjecture of Mihail and Vazirani asserts that the graph of every 0/1-polytope has edge-expansion at least 1. In this paper, we show that typical 0/1-polytopes have significantly stronger expansion. Specifically, if VV is formed by sampling each vertex of {0,1}n\{0,1\}^n independently with constant probability pp, then with high probability the edge-expansion is Θ(n)\Theta(n) for p(1/2,1)p \in (1/2, 1), and nΘ(loglogn)n^{\Theta(\log \log n)} for p(0,1/2)p \in (0, 1/2). This improves the previously best known bound Ω(1)\Omega(1) due to Ferber, Krivelevich, Sales and Samotij.

Keywords

Cite

@article{arxiv.2604.09520,
  title  = {Random 0/1-polytopes expand rapidly},
  author = {He Guo and István Tomon},
  journal= {arXiv preprint arXiv:2604.09520},
  year   = {2026}
}

Comments

21 pages

R2 v1 2026-07-01T12:03:13.683Z