报告题目：3+1D topological quantum field theory and quantum gravity

报 告 人：顾正澄， 香港中文大学

报告时间：2018-03-29 16:00

报告地点：理科楼郑裕彤讲堂

报告摘要：Topological quantum field theory (TQFT) is a very powerful theoretical tool to study topological phases and phase transitions. In 2+1D, it is well known that the Chern-Simons theory captures all the universal topological data of topological phases, e.g., quasi-particle braiding statistics, chiral central charge and even provides us a deep insight into the nature of topological phase transitions. Recently, topological phases of quantum matter are also intensively studied in 3+1D and it has been shown that loop like excitations obey the so-called three-loop-braiding statistics. In this talk, I will discuss a TQFT framework to understand the quantum statistics of loop like excitations in 3+1D. Most surprisingly, this new class of 3+1D TQFT even provides us a new route towards a quantum theory of gravity.