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arXiv · 2212.01311

Disjoint faces in simple drawings of the complete graph and topological Heilbronn problems

Alfredo Hubard·Andrew Suk
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Abstract

Given a complete simple topological graph $G$, a $k$-face generated by $G$ is the open bounded region enclosed by the edges of a non-self-intersecting $k$-cycle in $G$. Interestingly, there are complete simple topological graphs with the property that every odd face it generates contains the origin. In this paper, we show that every complete $n$-vertex simple topological graph generates at least $\Omega(n^{1/3})$ pairwise disjoint 4-faces. As an immediate corollary, every complete simple topological graph on $n$ vertices drawn in the unit square generates a 4-face with area at most $O(n^{-1/3})$. Finally, we investigate a $\mathbb Z_2$ variant of Heilbronn triangle problem.

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BibTeXRIS

Alfredo Hubard, Andrew Suk. 2022-12-02. Disjoint faces in simple drawings of the complete graph and topological Heilbronn problems. https://arxiv.org/abs/2212.01311

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