Geometry and Topology Seminar —— How does the plumbing operation constructs all knots and links?
报告人：段剑儒（北京大学）
时间：2025-05-21 15:10-17:00
地点：智华楼四元厅
【摘要】
The plumbing of two Seifert surfaces in the 3-sphere is an operation of knots and links introduced by Murasugi 60 years ago. A deep result of Harer and Giroux-Goodman shows that every fibered link is obtained by plumbing operation using only Hopf bands. For general non-fibered links, the question is very subtle and depends on the guts of the link. In this talk, I will introduce this question in a friendly way, show its connection with sutured manifold theory, and share some recent findings related to the L^2-leading coefficients of links.
