Topology Seminar

Date: March 22, 2023

Time: 4:00PM - 5:00PM

Location: BLOC 628

Speaker: Lei Chen, University of Maryland

Title: Mapping class groups of circle bundles over a surface

Abstract: In this talk, we study the algebraic structure of mapping class group Mod(M) of 3-manifolds M that fiber as a circle bundle over a surface S1 → M → Sg. We prove an exact sequence 1 → H1(Sg) → Mod(M) → Mod(Sg) → 1, relate this to the Birman exact sequence, and determine when this sequence splits. This is joint work with Bena Tshishiku.