Oct 17

Title: J-holomorphic curves in Stein domains and the tau-invariant

Speaker: Antonio Alfieri (CRM-ISM)

Abstract: The tau-invariant is a numerical invariant associated to a knot/link in a spinc rational homology three-sphere (Ozsvath and Szabo). In the case when the plane distribution of the spinc structure is of contact type one can use the Heegaard Floer contact class to get a more refined invariant (Hedden). I will discuss how the two invariants are related to each other, and how to make computations in the special case when the contact structure admits a Stein filling. This is joint work with Alberto Cavallo, and it is based on some work by Kyle Hayden.