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arXiv · 2201.11901

Graded extensions of generalized Haagerup categories

Pinhas Grossman·Masaki Izumi·Noah Snyder
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Abstract

We classify certain $\mathbb{Z}_2 $-graded extensions of generalized Haagerup categories in terms of numerical invariants satisfying polynomial equations. In particular, we construct a number of new examples of fusion categories, including: $\mathbb{Z}_2 $-graded extensions of $\mathbb{Z}_{2n} $ generalized Haagerup categories for all $n \leq 5 $; $\mathbb{Z}_2 \times \mathbb{Z}_2 $-graded extensions of the Asaeda-Haagerup categories; and extensions of the $\mathbb{Z}_2 \times \mathbb{Z}_2 $ generalized Haagerup category by its outer automorphism group $A_4 $. The construction uses endomorphism categories of operator algebras, and in particular, free products of Cuntz algebras with free group C$^*$-algebras.

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Pinhas Grossman, Masaki Izumi, Noah Snyder. 2022-01-28. Graded extensions of generalized Haagerup categories. https://arxiv.org/abs/2201.11901

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