Ander Lamaison: Ramsey upper density of infinite graphs

Abstract: Let H be an infinite graph. In a two-coloring of the edges of the complete
graph on the natural numbers, what is the densest monochromatic subgraph
isomorphic to H that we are guaranteed to find? We measure the density of a
subgraph by the upper density of its vertex set. This question, in the
particular case of the infinite path, was introduced by Erdős and Galvin.
Following a recent result for the infinite path, we present bounds on the
maximum density for other choices of H, including exact values for wide classes
of bipartite graphs and infinite factors.

Zoom link: https://zoom.us/j/2961946869