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arXiv · 2305.02000

LHS-spectral sequences for regular extensions of categories

Ergun Yalcin
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Abstract

In [F. Xu, On the cohomology rings of small categories, J. Pure Appl. Algebra 212 (2008), 2555-2569], Xu constructs a LHS-spectral sequence for target regular extensions of small categories. We extend this construction to ext-groups and construct a similar spectral sequence for source regular extensions (with right module coefficients). As a special case of these LHS-spectral sequences, we obtain three different versions of Slominska's spectral sequence for the cohomology of regular EI-categories. We show that many well-known spectral sequences related to the homology decompositions of finite groups, centric linking systems, and the orbit category of fusion systems can be obtained as the LHS-spectral sequence of an extension.

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Ergun Yalcin. 2023-05-03. LHS-spectral sequences for regular extensions of categories. https://arxiv.org/abs/2305.02000

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