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arXiv · 1809.05121

Singular Hochschild cohomology via the singularity category

Bernhard Keller
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Abstract

We show that for a noetherian algebra $A$ whose bounded dg derived category is smooth, the singular Hochschild cohomology (=Tate--Hochschild cohomology) is isomorphic, as a graded algebra, to the Hochschild cohomology of the dg singularity category of $A$. The existence of such an isomorphism is suggested by recent work of Zhengfang Wang.

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BibTeXRIS

Bernhard Keller. 2018-09-13. Singular Hochschild cohomology via the singularity category. https://arxiv.org/abs/1809.05121

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