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arXiv · 1702.06333

Cohomology and extensions of ordered groupoids

B. O. Bainson·N. D. Gilbert
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Abstract

We adapt and generalise results of Loganathan on the cohomology of inverse semigroups to the cohomology of ordered groupoids. We then derive a five-term exact sequence in cohomology from an extension of ordered groupoids, and show that this sequence leads to a classification of extensions by a second cohomology group. Our methods use structural ideas in cohomology as far as possible, rather than computation with cocycles.

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B. O. Bainson, N. D. Gilbert. 2017-02-21. Cohomology and extensions of ordered groupoids. https://arxiv.org/abs/1702.06333

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