Combinatorics Seminar 2015

Speaker: Sebastian M. Cioabă, University of Delaware

Date: Thu, Sep 17, 2015

Time: 14:00 - 15:00

Venue: Large Meeting Room

Title: Eigenvalues of graphs, small expanders and non-backtracking random walks


The eigenvalues of a graph provide important structural information. In particular, expansion and random walk properties of a graph are closely related to the graph spectrum. In this talk, I will discuss my recent work (with Koolen, Nozaki and Vermette) studying the largest order of a regular graph of given valency and second eigenvalue and (with my student Peng Xu) generalizing some results involving the mixing time of non-backtracking random walks of Alon, Benjamini, Lubetzky and Sodin.