2007/10/31 by Yorck Sommerhaeuser, Yongchang Zhu · 1 citation
Mathematics · Physics and Astronomy · #math.RA #hep-th #math-ph #math.MP #math.QA #math.RT #msc:16W30
published as Mem. Am. Math. Soc., Vol. 219, No. 1028, Am. Math. Soc., Providence, 2012 · 130 pages. Many new results added, remark by D. Nikshych included. See also http://www.southalabama.edu/mathstat/personal_pages/sommerh/
arxiv created 2008/02/06 · arxiv updated 2012/08/30
We prove that the kernel of the natural action of the modular group on the center of the Drinfel'd double of a semisimple Hopf algebra is a congruence subgroup. To do this, we introduce a class of generalized Frobenius-Schur indicators and endow it with an action of the modular group that is compatible with the original one.