Stefano Vidussi (UCRiverside)
January 28, 2020 @ 3:00 pm – 4:00 pm
Title: The BNS invariant of the fundamental group of a surface bundle over a surface.
Abstract: We will discuss some new results on the Bieri-Neumann-Strebel invariant of these groups, showing in particular that (with obvious exceptions) they algebraically fiber. As a corollary, we show that for “most” bundles these groups are not coherent.