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Geometry-Topology Seminar

Thursday, October 25, 2018 - 4:30pm

Ana Menezes and Jonathan Hanselman

Princeton University


University of Pennsylvania


This will be a "double header" seminar, with Ana's talk at 4:30 PM and Jonathan's at 5:45 PM, with dinner afterwards. This seminar is sponsored jointly with Bryn Mawr, Haverford and Temple.

Title for Ana Menezes: "Minimal surfaces in homogeneous spaces"


Abstract: In this talk we will consider some results concerning minimal surfaces in homogeneous spaces. In particular, we will consider a multi-valued Rado theorem for small perturbations of the Helicoid in H2xR and we will prove that for certain small perturbations of the boundary of a (compact) helicoid there exists only one minimal disk with that boundary.
Title for Jonathan Hanselman: "Heegaard Floer invariants for manifolds with torus boundary via immersed curves"
Abstract:  Heegaard Floer homology is an important topological invariant of closed 3-dimensional manifolds. I will describe a relative version of this invariant in the case of torus boundary: to a 3-manifold with torus boundary, we can associate an element of the Fukaya category of the punctured torus—that is, a collection of decorated immersed curves in the torus—so that when two such manifolds are glued the Heegaard Floer homology of the resulting 3-manifold is recovered from the intersection of the corresponding curves. These curves are a reformulation of the bordered Heegaard Floer invariants defined by Lipshitz, Ozsvath, and Thurston, but their geometric nature makes them more user friendly. We will discuss some properties of these curves and some nice applications, including a rank inequality for Heegaard Floer homology of toroidal manifolds and invariance of Heegaard Floer homology under genus one mutation. This is joint work with J. Rasmussen and L. Watson.