English

Frobenius-Schur indicator for categories with duality

Representation Theory 2012-11-21 v2 Category Theory

Abstract

We introduce the Frobenius-Schur indicator for categories with duality to give a category-theoretical understanding of various generalizations of the Frobenius-Schur theorem, including that for semisimple quasi-Hopf algebras, weak Hopf C*-algebras and association schemes. Our framework also clarifies a mechanism how the `twisted' theory arises from the ordinary case. As a demonstration, we give a twisted Frobenius-Schur theorem for semisimple quasi-Hopf algebras. We also give several applications to the quantum SL_2.

Keywords

Cite

@article{arxiv.1208.2433,
  title  = {Frobenius-Schur indicator for categories with duality},
  author = {Kenichi Shimizu},
  journal= {arXiv preprint arXiv:1208.2433},
  year   = {2012}
}

Comments

38 pages; final version published in the Special Issue on "Hopf Algebras, Quantum Groups and Yang-Baxter Equations" of Axioms

R2 v1 2026-06-21T21:49:32.408Z