Ramsey simplicity of random graphs
Abstract
A graph is -Ramsey for another graph if in any -edge-colouring of there is a monochromatic copy of , and the classic Ramsey problem asks for the minimum number of vertices in such a graph. This was broadened in the seminal work of Burr, Erd\H{o}s, and Lov\'asz to the investigation of other extremal parameters of Ramsey graphs, including the minimum degree. It is not hard to see that if is minimally -Ramsey for we must have , and we say that a graph is -Ramsey simple if this bound can be attained. Grinshpun showed that this is typical of rather sparse graphs, proving that the random graph is almost surely -Ramsey simple when . In this paper, we explore this question further, asking for which pairs and we can expect to be -Ramsey simple. We resolve the problem for a wide range of values of and ; in particular, we uncover some interesting behaviour when .
Keywords
Cite
@article{arxiv.2109.04140,
title = {Ramsey simplicity of random graphs},
author = {Simona Boyadzhiyska and Dennis Clemens and Shagnik Das and Pranshu Gupta},
journal= {arXiv preprint arXiv:2109.04140},
year = {2025}
}
Comments
29 pages, 2 figures