Tuesday, September 8, 2020
Math Seminar Series
(Conferences / Seminars / Lectures)
Geometry and Topology more information...
Yi Ni from Caltech, will be speaking on the topic of Thurston norm minimizing Seifert surfaces.
Place: Online (virtual meeting)
Let K be a null-homologous knot in a closed 3-manifold Y, and F be a Seifert surface. One can cap off the boundary of F with a disk in the zero surgery on K to get a closed surface F_0. If we know that F is Thurston norm minimizing, we can ask whether F_0 is also Thurston norm minimizing. A classical theorem of Gabai says that the answer is Yes when Y is the 3-sphere. Gabai's theorem can be generalized to many other 3-manifolds using Heegaard Floer homology. In this talk, we will discuss a sufficient condition for F_0 to be Thurston norm minimizing which relates this property to the 4-genus of the knot.