## Geometry/Topology Seminar Schedule

Please see the following for more related talks:

The Geometry/Topology seminar is organized this academic year (2017-2018) by Ákos Nagy and Michael Abel

Upcoming Seminars:
• Monday, February 25, 2019, 3:15pm, 119 Physics, Triangle Topology Seminar
Fillability of contact surgeries and Lagrangian discs
Bulent Tosun (University of Alabama)

It is well known that all contact 3-manifolds can be obtained from the standard contact structure on the 3-sphere by contact surgery on a Legendrian link. Hence, an interesting and much studied question asks what properties of a contact structure are preserved under various types of contact surgeries. The case for the negative contact surgeries is fairly well understood. In this talk, we will discuss some new results about positive contact surgeries and in particular completely characterize when contact (r) surgery is symplectically/Stein fillable for r in (0,1]. This is joint work with James Conway and John Etnyre.

• Thursday, February 28, 2019, 3:15pm, 119 Physics, Geometry/topology Seminar
Singularity formation in geometric flows
Simon Brendle (Columbia University, Mathematics)

Geometric evolution equations like the Ricci flow and the mean curvature flow play a central role in differential geometry. The main problem is to understand singularity formation. In this talk, I will discuss recent results which give a complete picture of all the possible limit flows in 2D mean curvature flow with positive mean curvature, and in 3D Ricci flow.

• Monday, March 4, 2019, 3:15pm, 119 Physics, Geometry/topology Seminar
Classification of Nahm Pole Solutions to the KW Equations on $S^1\times\Sigma\times R^+$
Siqi He (Simons Center for Geometry and Physics)

We will discuss Witten’s gauge theory approach to Jones polynomial by counting solutions to the Kapustin-Witten (KW) equations with singular boundary conditions over 4-manifolds. We will give a classification of solutions to the KW equations over $S^1\times\Sigma\times R^+$. We prove that all solutions to the KW equations over $S^1\times\Sigma\times R^+$ are $S^1$ direction invariant and we give a classification of the KW monopole over $\Sigma\times R^+$ based on the Hermitian-Yang-Mills type structure of KW monopole equation. This is based on joint works with Rafe Mazzeo.

• Monday, March 18, 2019, 3:15pm, 119 Physics, Geometry/topology Seminar
TBA
Mark A. Stern

TBA

• Monday, March 25, 2019, 3:15pm, 119 Physics, Triangle Topology Seminar
TBA
Lisa Traynor (Bryn Mawr College)

TBA

• Monday, April 8, 2019, 3:15pm, 119 Physics, Geometry/topology Seminar
TBA
Nathan Dowlin (Dartmouth College, Mathematics)