S4-symmetry of 6j-symbols and Frobenius--Schur indicators in rigid monoidal C-categories
نویسنده
چکیده
We show that a left-rigid monoidal C-category with irreducible monoidal unit is also a sovereign and spherical category. Defining a Frobenius--Schur type indicator we obtain selection rules for the fusion coefficients of irreducible objects. As a main result we prove S4-invariance of 6j-symbols in such a category.
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تاریخ انتشار 1998