RTG Seminar on Geometry, Dynamics and Topology Seminar

In this talk we will consider a discrete group acting on the circle by orientation-preserving homeomorphisms and review some of the properties of the Euler class associated to this action. In particular, we will be interested in the Euler class associated to the Nielsen action on the circle of the mapping class group of an orientable surface with one marked point. We will describe some partial results, in ongoing work with Solomon Jekel, on the vanishing and non-vanishing behaviour of the powers of this class. Speaker(s): Rita Jiménez Rolland (Universidad Nacional Autónoma de México)