English

On short edges in complete topological graphs

Combinatorics 2023-12-05 v2 Computational Geometry

Abstract

Let h(n)h(n) be the minimum integer such that every complete nn-vertex simple topological graph contains an edge that crosses at most h(n)h(n) other edges. In 2009, Kyn\v{c}l and Valtr showed that h(n)=O(n2/log1/4n)h(n) = O(n^2/\log^{1/4} n), and in the other direction, gave constructions showing that h(n)=Ω(n3/2)h(n) = \Omega(n^{3/2}). In this paper, we prove that h(n)=O(n7/4)h(n) = O(n^{7/4}). Along the way, we establish a new variant of Chazelle and Welzl's matching theorem for set systems with bounded VC-dimension, which we believe to be of independent interest.

Keywords

Cite

@article{arxiv.2307.08165,
  title  = {On short edges in complete topological graphs},
  author = {Andrew Suk},
  journal= {arXiv preprint arXiv:2307.08165},
  year   = {2023}
}
R2 v1 2026-06-28T11:31:59.013Z