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arXiv · 2610.28828

A counterexample to Gale's conjecture in $\mathbb{R}^3$

Vsevolod Voronov
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Abstract

It is known that for every partition of the sphere $S^2$ of unit diameter into four parts, the largest diameter of a part is at least $\sqrt{(3+\sqrt{3})/6} = 0.88807\dots$, and this bound is attained. The conjecture of D.~Gale (1953) asserts that no set in $\mathbb{R}^3$ has a larger ratio. In this paper, we construct a $101$-point set $V\subset\mathbb{R}^3$ such that every partition of $V$ into four parts contains a part of diameter greater than $0.88928 \, \operatorname{diam} V$.

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Vsevolod Voronov. 2026-10-20. A counterexample to Gale's conjecture in $\mathbb{R}^3$. https://arxiv.org/abs/2610.28828

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