Topology Seminar: An infinite presentation for the Torelli group

The Torelli group is the subgroup of the mapping class group of a surface which acts trivially on the surface's first homology group. Despite the pioneering work of Birman, Johnson, and many others numerous basic questions about it remain open. I will begin by describing some history and background, and then I will discuss a new (infinite) presentation of the Torelli group whose generators and relations have simple topological interpretations.