時間：2019年7月5日（星期五）  10:00-11:00

地點：數理學院教2樓108室

講座題目：The generalized Yamada polynomial of virtual spatial graphs

主講人：金賢安教授

講座摘要：Knot theory can be generalized to virtual knot theory and spatial graph theory. In 2007, Fleming and Mellor combined and generalized them to virtual spatial graph theory in a combinatorial way.

In this talk, we shall generalize the classical Yamada polynomial for spatial graphs to obtain the generalized Yamada polynomial for virtual spatial graphs via their diagrams. Then we prove that it can be normalized to be a rigid vertex isotopic invariant of virtual spatial graphs and to be a pliable vertex isotopic invariant for virtual spatial graphs with maximum degree at most 3.

We also consider the connection and difference between the generalized Yamada polynomial and the Dubrovnik polynomial of a classical link. That is, the generalized Yamada polynomial specializes to a version of the Dubrovnik polynomial for classical links such that it can be used to sometimes detect the non-classicality of virtual links.This is joint work with Qingying Deng and Louis H. Kauffman.

專家簡介：金賢安，廈門大學數學科學學院教授，博士生導師，副院長。主要從事圖論、組合紐結論及其應用的研究工作。迄今為止，已在Adv. Appl. Math., J. Graph Theory, Proc. Amer. Math. Soc. ,Topol. Appl.等雜志發表學術論文50餘篇。先後主持國家自然科學基金項目3項，參加國家自然科學基金重點項目1項。曾在第6屆組合數學與圖論大會、中國數學會2013年和2018年學術年會、第7屆亞洲數學大會、The 33rd Summer Conference on Topology and its Applications等國際和國内學術會議作邀請報告。

歡迎廣大師生參加！

數理學院