Bounded degree graphs and hypergraphs with no full rainbow matchings
Abstract
Given a multi-hypergraph that is edge-colored into color classes , a full rainbow matching is a matching of that contains exactly one edge from each color class . One way to guarantee the existence of a full rainbow matching is to have the size of each color class be sufficiently large compared to the maximum degree of . In this paper, we apply a simple iterative method to construct edge-colored multi-hypergraphs with a given maximum degree, large color classes, and no full rainbow matchings. First, for every and , we construct edge-colored -uniform multi-hypergraphs with maximum degree such that each color class has size and there is no full rainbow matching, which demonstrates that a theorem of Aharoni, Berger, and Meshulam (2005) is best possible. Second, we construct properly edge-colored multigraphs with no full rainbow matchings which disprove conjectures of Delcourt and Postle (2022). Finally, we apply results on full rainbow matchings to list edge-colorings and prove that a color degree generalization of Galvin's theorem (1995) does not hold.
Cite
@article{arxiv.2401.06029,
title = {Bounded degree graphs and hypergraphs with no full rainbow matchings},
author = {Ronen Wdowinski},
journal= {arXiv preprint arXiv:2401.06029},
year = {2025}
}