Coordinates: JH Michell Theatre in the Richard Berry Building
Speaker: Shicheng Wang (Peking University)
Title: Graph manifolds have virtually positive Seifert volume
Abstract: (Joint work with Pierre Derbez.)

The Seifert volume of each closed non-trivial graph manifold is virtually positive. Then for each closed orientable 3-manifold N, the set of mapping degrees D(M,N) is finite for any 3-manifold M, unless each prime factor of N is finitely covered by either a torus bundle, or a trivial circle bundle, or the 3-sphere.