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arXiv · 2411.05931

A New Class of Geometrically Defined Hypergraphs Arising from the Hadwiger Nelson Problem

Sean Fiscus·Eric Myzelev·Hongyi Zhang
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Abstract

There is a famous problem in geometric graph theory to find the chromatic number of the unit distance graph on Euclidean space; it remains unsolved. A theorem of Erdos and De-Bruijn simplifies this problem to finding the maximum chromatic number of a finite unit distance graph. Via a construction built on sequential finite graphs obtained from a generalization of this theorem, we have found a class of geometrically defined hypergraphs of arbitrarily large edge cardinality, whose proper colorings exactly coincide with the proper colorings of the unit distance graph on $\mathbb R^d$. We also provide partial generalizations of this result to arbitrary real normed vector spaces.

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Sean Fiscus, Eric Myzelev, Hongyi Zhang. 2024-11-08. A New Class of Geometrically Defined Hypergraphs Arising from the Hadwiger Nelson Problem. https://arxiv.org/abs/2411.05931

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