Topology Seminar: Analogs of the curve graph for infinite type surfaces

Seminar | September 18 | 4:10-5 p.m. | 3 Evans Hall

 Alexander Rasmussen, Yale University

 Department of Mathematics

The mapping class group of a finite type surface acts on its curve graph. This action has proven to be crucial for understanding the mapping class group and many of the applications rely on the fact that the curve graph is hyperbolic and infinite diameter. We will describe several actions of mapping class groups of infinite type surfaces on hyperbolic graphs analogous to the curve graph. In particular, we will focus on the pros and cons of these various actions, finer points of the geometry of the corresponding graphs, and applications to bounded cohomology.