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arXiv · 2608.09062

Rickard's question on standard derived equivalences

Wei Hu·Changchang Xi·Jin Zhang
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Abstract

In 1991 Rickard asked whether every derived equivalence of algebras over a common field is standard. We construct a series of examples of non-standard derived equivalences, and thus answer the question negatively. Moreover, we give a necessary and sufficient condition for the question to be true.

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Wei Hu, Changchang Xi, Jin Zhang. 2026-09-02. Rickard's question on standard derived equivalences. https://arxiv.org/abs/2608.09062

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