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arXiv · 2403.09299

Reflexivity and Hochschild Cohomology

Isambard Goodbody
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Abstract

We characterise reflexive DG-categories, as introduced by Kuznetsov and Shinder, as the reflexive objects in the closed symmetric monoidal category of DG-categories localised at Morita equivalences. As consequences, we show that the Hochschild cohomology and the derived Picard group of a reflexive DG-category coincide with those of its derived category of cohomologically finite modules.

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Isambard Goodbody. 2024-03-14. Reflexivity and Hochschild Cohomology. https://arxiv.org/abs/2403.09299

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