**5 pm – 6 pm, February 17 (coming Monday)**

**Fine 314**

**Who:**

**Prof. Paul Yang, whose interest lies in differential geometry and geometric analysis**

**here are the title and abstracts**

Abstract:

I will explain the geometry of a contact form in dimension three. The basic problem is to find the isoperimetric profile in the Heisenberg group. This variational problem is approached via a mean curvature equation. However this equation is not an elliptc equation in this low dimension, hence the problem remains largely open due to regularity issues.