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arXiv · 2005.01087

Hochschild cohomology of twisted tensor products

Benjamin Briggs·Sarah Witherspoon
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Abstract

For a tensor product of algebras twisted by a bicharacter, we completely describe its Hochschild cohomology, as a Gerstenhaber algebra, in terms of the Hochschild cohomology of its component parts. This description generalizes a result of Bergh and Oppermann. It allows us to significantly simplify various calculations in the literature, and to compute Hochschild cohomology for a number of new examples.

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Benjamin Briggs, Sarah Witherspoon. 2020-05-03. Hochschild cohomology of twisted tensor products. https://arxiv.org/abs/2005.01087

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