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arXiv · 2212.14497

Derived categories of curves of genus one and torsors over abelian varieties

Niranjan Ramachandran·Jonathan Rosenberg
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Abstract

Suppose $C$ is a smooth projective curve of genus 1 over a perfect field $F$, and $E$ is its Jacobian. In the case that $C$ has no $F$-rational points, so that $C$ and $E$ are not isomorphic, $C$ is an $E$-torsor with a class $\delta(C)\in H^1(\text{Gal}(\bar F/F), E(\bar F))$. Then $\delta(C)$ determines a class $\beta \in \text{Br}(E)/\text{Br}(F)$ and there is a Fourier-Mukai equivalence of derived categories of (twisted) coherent sheaves $\mathcal D(C) \xrightarrow{\cong} \mathcal D(E, \beta^{-1})$. We generalize this result to higher dimensions; namely, we prove it also for torsors over abelian varieties.

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Niranjan Ramachandran, Jonathan Rosenberg. 2022-12-30. Derived categories of curves of genus one and torsors over abelian varieties. https://doi.org/10.4310/mrl.250708032422

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