Topology Seminar (Introductory Talk): Trisections of finitely presented groups.

Seminar | April 6 | 2:10-3 p.m. | 740 Evans Hall

 Rob Kirby, UC Berkeley

 Department of Mathematics

I will define a trisection of a finitely presented group and show that it determines a unique smooth, closed, oriented 4-manifold X. Next is the theorem that every f.p. group has a trisection. But the set of such trisections correspond roughly to the 4-manifolds with a given fundamental group. The second hour will be devoted to the notion of trisections of 4-manifolds and how they relate to the trisections of groups. This is joint work with Dave Gay.