English

Transversal generalizations of hyperplane equipartitions

Combinatorics 2023-11-10 v3 Algebraic Topology

Abstract

The classical Ham Sandwich theorem states that any dd point sets in Rd\mathbb{R}^d can be simultaneously bisected by a single affine hyperplane. A generalization of Dolnikov asserts that any dd families of pairwise intersecting compact, convex sets in Rd\mathbb{R}^d admit a common hyperplane transversal. We extend Dolnikov's theorem by showing that families of compact convex sets satisfying more general non-disjointness conditions admit common transversals by multiple hyperplanes. In particular, these generalize all known optimal results to the long-standing Gr\"unbaum--Hadwiger--Ramos measure equipartition problem in the case of two hyperplanes. Our proof proceeds by establishing topological Radon-type intersection theorems and then applying Gale duality in the linear setting. For a single hyperplane, this gives a new proof of Dolnikov's original result via Sarkaria's non-embedding criterion for simplicial complexes.

Keywords

Cite

@article{arxiv.2210.15423,
  title  = {Transversal generalizations of hyperplane equipartitions},
  author = {Florian Frick and Samuel Murray and Steven Simon and Laura Stemmler},
  journal= {arXiv preprint arXiv:2210.15423},
  year   = {2023}
}

Comments

24 pages

R2 v1 2026-06-28T04:38:36.043Z