Seminars & Colloquia Calendar
Ramsey upper density of infinite graphs
Ander Lamaison (Freie Universität Berlin)
Location: Hill 705
Date & time: Monday, 10 February 2020 at 2:00PM - 3:00PM
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 Erd?s 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 a wide class of bipartite graphs.