Computing Higher Frobenius-schur Indicators in Fusion Categories Constructed from Inclusions of Finite Groups
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چکیده
We consider a subclass of the class of group-theoretical fusion categories: To every finite group G and subgroup H one can associate the category of G-graded vector spaces with a two-sided H-action compatible with the grading. We derive a formula that computes higher Frobenius-Schur indicators for the objects in such a category using the combinatorics and representation theory of the groups involved in their construction. We calculate some explicit examples for inclusions of symmetric groups.
منابع مشابه
A Higher Frobenius-schur Indicator Formula for Group-theoretical Fusion Categories
Group-theoretical fusion categories are defined by data concerning finite groups and their cohomology: A finite group G endowed with a three-cocycle ω, and a subgroup H ⊂ G endowed with a two-cochain whose coboundary is the restriction of ω. The objects of the category are G-graded vector spaces with suitably twisted H-actions; the associativity of tensor products is controlled by ω. Simple obj...
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تاریخ انتشار 2017