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On the Frobenius-Schur indicators for quasi-Hopf algebras

Peter Schauenburg
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Abstract

Mason and Ng have given a generalization to semisimple quasi-Hopf algebras of Linchenko and Montgomery's generalization to semisimple Hopf algebras of the classical Frobenius-Schur theorem for group representations. We give a simplified proof, in particular a somewhat conceptual derivation of the appropriate form of the Frobenius-Schur indicator that indicates if and in which of two possible fashions a given simple module is self-dual.

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Peter Schauenburg. 2003-09-07. On the Frobenius-Schur indicators for quasi-Hopf algebras. https://arxiv.org/abs/math/0309131

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