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arXiv · 2201.04076

Computing the group of minimal non-degenerate extensions of a super-Tannakian category

Dmitri Nikshych
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Abstract

We prove an analog of the K\"unneth formula for the groups of minimal non-degenerate extensions arXiv:1602.05936 of symmetric fusion categories. We describe in detail the structure of the group of minimal extensions of a pointed super-Tannakian fusion category. This description resembles that of the third cohomology group of a finite abelian group. We explicitly compute this group in several concrete examples.

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Dmitri Nikshych. 2022-01-11. Computing the group of minimal non-degenerate extensions of a super-Tannakian category. https://doi.org/10.1007/s00220-022-04478-8

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