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arXiv · 2605.29432

Autoduality of compactified Pryms for \'etale double covers of curves with planar singularities

Huishi Yu
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Abstract

We construct a Poincar\'e sheaf on the compactified Prym variety associated with an \'etale double cover of integral curves with planar singularities, and prove that the associated Fourier-Mukai transform is an autoequivalence of its derived category. As an application, we prove the motivic decomposition conjecture of Corti-Hanamura for the Laza-Sacc\`a-Voisin fibration, and construct a multiplicative motivic perverse filtration lifting the cohomological one.

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Huishi Yu. 2026-05-28. Autoduality of compactified Pryms for \'etale double covers of curves with planar singularities. https://arxiv.org/abs/2605.29432

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