报告题目：Spectral extrema and subgraph counting (谱极值与子图计数)

报告人：翟明清，滁州学院

时间：2022年5月24日(星期二) 14:30

腾讯会议：421 320 887

摘要：Spectral extremal problem, proposed by Nikiforov, asks what is the maximum spectral radius of an $H$-free graph on $n$ vertices? This problem has attracted appreciable amount of interest in the past decades. Let $\rho(G)$ be the spectral radius of a graph $G$ and $spex(n,H)$ be the extremal spectral radius of the above problem. One can immediately obtain that if $\rho(G)>spex(n,H)$, then $G$ contains at least one copy of $H$. We further want to know what is the minimum number of copies of $H$ in a graph $G$ provided that $\rho(G)>spex(n,H)$. In this talk, we introduce some pioneering results on spectral extrema and subgraph counting. Some recent results of us are also mentioned.

报告人简介：翟明清，滁州学院教授，2010年博士毕业于华东师范大学运筹学与控制论专业，2012年获评教授，2013年获评安徽省学术技术带头人后备人选, 2022年入选安徽师范大学外聘博士生导师。近年来在LAA, DM, LMA, EUJC, EJC等期刊发表学术论文40余篇，主持国家自然科学基金2项。研究方向：图谱理论，谱极值图论。