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arXiv · 1202.4396

The Brauer-Picard group of the Asaeda-Haagerup fusion categories

Pinhas Grossman·Noah Snyder
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Abstract

We prove that the Brauer-Picard group of Morita autoequiv- alences of each of the three fusion categories which arise as an even part of the Asaeda-Haagerup subfactor or of its index 2 extension is the Klein four-group. We describe the 36 bimodule categories which occur in the full subgroupoid of the Brauer-Picard groupoid on these three fusion categories. We also classify all irreducible subfactors both of whose even parts are among these categories, of which there are 111 up to isomorphism of the planar algebra (76 up to duality). Although we identify the entire Brauer-Picard group, there may be additional fusion categories in the groupoid. We prove a partial classification of possible additional fusion categories Morita equivalent to the Asaeda-Haagerup fusion categories and make some conjectures about their existence; we hope to address these conjectures in future work.

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Pinhas Grossman, Noah Snyder. 2012-02-20. The Brauer-Picard group of the Asaeda-Haagerup fusion categories. https://arxiv.org/abs/1202.4396

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