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arXiv · 2501.10192

Lefschetz Defect in Families

Matteo Verni
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Abstract

We provide a cohomological characterization of the Lefschetz defect of smooth complex projective varieties. As a consequence, we deduce that the Lefschetz defect of a smooth Fano variety is invariant under smooth deformation. We also characterize the Lefschetz defect of an abelian variety in terms of its isogeny factors, and study it in families.

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Matteo Verni. 2025-01-17. Lefschetz Defect in Families. https://arxiv.org/abs/2501.10192

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