报告题目：Frobenius-Schur indicators and exponents of finite groups and fusion categories
报告人： Siu-Hung Ng (Louisiana State University)
摘要：The exponent of a finite group is an invariant of the tensor category of its complex representations. Using Frobenius-Schur indicators, one can rediscover the Cauchy theorem for finite groups in terms of their exponents and orders. In this talk, we introduce the Frobenius-Schur indicators for Hopf algebras as well as fusion categories. Moreover, we discuss some of their arithmetic properties and applications to the congruence subgroup theorem and the Cauchy theorem for fusion categories.