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arXiv · 2002.06671

An outline of obstruction theories of extensions via track categories

Mariam Pirashvili
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Abstract

Abelian track categories can be classified via the third Baues-Wirsching cohomology of small categories. This approach is used in this paper to compare and classify different generalisations of the obstruction theory of non-abelian group extensions, due to Cegarra, Garz\'on and Grandjean, Cegarra, Garz\'on and Ortega, and Chen, Du and Wang.

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Mariam Pirashvili. 2020-02-16. An outline of obstruction theories of extensions via track categories. https://arxiv.org/abs/2002.06671

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