报告题目：On the colorability of bi-hypergraphs
报告人：董峰明教授，南洋理工大学
报告时间：2024年6月3日（周一）14:30-15:30
报告地点：20-200
报告摘要：Graph coloring is one of the most important and long-standing topics in graph theory. Not only does it tie many concepts in graph theory in surprising ways, but it also has a wide range of real-world applications. This talk will focus on the colorability of bi-hypergraphs. A mixed hypergraph H = (V, C, D) consists of the vertex set V and two families of subsets of V: the family C of co-edges and the family D of edges. H is said to be colorable if there is a mapping f from V to the set of positive integers such that |{f(v) : v ∈ e}| < |e| for each e ∈ C and |{f(v) : v ∈ e}| > 1 for each e ∈ D. There exist mixed hypergraphs which are uncolorable, and quite little about these mixed hypergraphs is known. A mixed hypergraph is called a bi-hypergraph if its co-edge set and edge set are the same. In this talk, I will introduce our recent research on the size of minimal uncolorable bi-hypergraphs.
This is a joint work with Meiqiao Zhang and Ruixue Zhang.
报告人简介：董峰明教授，1997年于新加坡国立大学获博士学位，任教于南洋理工大学，是图多项式领域的国际著名专家。在图多项式、染色、匹配、生成树等图论与组合数学的很多领域作出了重要工作，例如证明了色多项式的Shameful Conjecture等， 在J. Combin. Theory Ser. B，J. Combin. Theory Ser. A，Combin. Probab. Comput.，SIAM J. Discrete Math.，J. Graph Theory等组合数学顶级杂志上发表论文多篇。