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arXiv · 2008.01471

Cohomology of Topologised Monoids

Abstract

We prove standard results of group cohomology -- namely, existence of a long exact sequence, classification of torsors via the first cohomology group, Shapiro's lemma, the Hochschild-Serre spectral sequence, a decomposition of the cochain complex in the direct product case, and Jannsen's result on the recovery problem -- for cohomology theories such as continuous, analytic, bounded, and pro-analytic cohomology. We also prove these results for certain monoids. The cohomology groups considered here all have very concrete interpretations by means of a cochain complex. Therefore, we do not use methods of homological algebra, but explicit calculations on the level of cochains, using techniques dating back to Hochschild and Serre.

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Oliver Thomas. 2020-08-04. Cohomology of Topologised Monoids. https://doi.org/10.1007/s00209-021-02954-w

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