English

The list-Ramsey threshold for families of graphs

Combinatorics 2024-11-27 v2

Abstract

Given a family of graphs F\mathcal{F} and an integer rr, we say that a graph is rr-Ramsey for F\mathcal{F} if any rr-colouring of its edges admits a monochromatic copy of a graph from F\mathcal{F}. The threshold for the classic Ramsey property in the binomial random graph, where F\mathcal{F} consists of one graph, was located in the celebrated work of R\"odl and Ruci\'nski. In this paper, we offer a twofold generalisation to the R\"odl--Ruci\'nski theorem. First, we show that the list-colouring version of the property has the same threshold. Second, we extend this result to finite families F\mathcal{F}, where the threshold statements might also diverge. This also confirms further special cases of the Kohayakawa--Kreuter conjecture. Along the way, we supply a short(-ish), self-contained proof of the 00-statement of the R\"odl--Ruci\'nski theorem.

Keywords

Cite

@article{arxiv.2305.19964,
  title  = {The list-Ramsey threshold for families of graphs},
  author = {Eden Kuperwasser and Wojciech Samotij},
  journal= {arXiv preprint arXiv:2305.19964},
  year   = {2024}
}