DMS Combinatorics Seminar

PLEASE NOTE NEW TIME: 9:00AM

Speaker: Debsoumya Chakraborti, Institute for Basic Science (IBS), South Korea

Title: Rainbow extremal problem for color-critical graphs

Abstract: Given $k$ graphs $G_1,\dots, G_k$ over a common vertex set of size $n$, what conditions on $G_i$ ensure a rainbow copy of $H$, i.e., a copy of $H$ with at most one edge from each $G_i$? We study the problem of maximizing $\sum_{i} e(G_i)$ without a rainbow copy of $H$, where $e(G_i)$ denotes the number of edges in the graph $G_i$. We discuss some results and open questions when $H$ is a complete or a color-critical graph. We also discuss our recent progress on this problem to a conjecture of Keevash, Saks, Sudakov, and Verstraete.

This talk will be based on joint work with Kim, Lee, Liu, and Seo.