Central Invariants and Frobenius-Schur Indicators for Semisimple Quasi-Hopf Algebras
نویسندگان
چکیده
In this paper, we obtain a canonical central element νH for each semisimple quasiHopf algebraH over an algebraically closed field of char 0 and prove that νH is invariant under gauge transformations. Moreover, if H is a semisimple Hopf algebra or a twisted quantum double of a finite group, then χ(νH) is the Frobenius-Schur Indicator of the irreducible representation which affords the character χ. We also prove an analog of a Theorem of Larson-Radford for semi-simple quasi-Hopf algebra. Using this result, we establish the relationship between the antipode S, the values of χ(νH), and certain associated bilinear forms.
منابع مشابه
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