1. Conflict-free Hypergraph Matchings and Coverings
- Author
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Joos, Felix, Mubayi, Dhruv, and Smith, Zak
- Subjects
Mathematics - Combinatorics - Abstract
Recent work showing the existence of conflict-free almost-perfect hypergraph matchings has found many applications. We show that, assuming certain simple degree and codegree conditions on the hypergraph $ \mathcal{H} $ and the conflicts to be avoided, a conflict-free almost-perfect matching can be extended to one covering all of the vertices in a particular subset of $ V(\mathcal{H}) $, by using an additional set of edges; in particular, we ensure that our matching avoids all of a further set of conflicts, which may consist of both old and new edges. This setup is useful for various applications, and our main theorem provides a black box which encapsulates many long and tedious calculations, massively simplifying the proofs of results in generalised Ramsey theory., Comment: 19 pages + 4 pages appendix
- Published
- 2024