# Time-reversal and reflection symmetry in (2+1)-dimensional topological phases

**Speaker:**Meng Cheng, Yale University

**When:**April 5, 2017 (Wed), 02:30PM to 03:30PM (add to my calendar)

**Location:**SCI 328

*This event is part of the Condensed Matter Theory Seminar Series. *

Abstract: There has been immense progress recently in the understanding of interacting topological phases of matter in the presence of symmetry. I will discuss recent developments for the case of time-reversal / reflection symmetry-enriched topological (SET) phases. I will derive a simple formula for the ground state degeneracy of such SETs on non-orientable manifold. I then use these results to develop an understanding of anomalies associated with time-reversal / reflection SETs. If time permits, I will discuss explicit constructions of time-reversal/reflection SETs, including anomalous ones.