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arXiv · 2407.20769

Jets-separation thresholds, Seshadri constants and higher Gauss-Wahl maps on abelian varieties

Nelson Alvarado
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Abstract

Given a closed subscheme $Z$ of a polarized abelian variety $(A,\ell)$ we define its vanishing threshold with respect to $\ell$ and relate it to the Seshadri constant of the ideal defining $Z.$ As a particular case, we introduce the notion of jets-separation thresholds, which naturally arise as the vanishing threshold of the $p$-infinitesimal neighborhood of a point. Afterwards, by means of Fourier-Mukai methods we relate the jets-separation thresholds with the surjectivity of certain higher Gauss-Wahl maps. As a consequence we obtain a criterion for the surjectivity of those maps in terms of the Seshadri constant of the polarization $\ell.$

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Nelson Alvarado. 2024-07-30. Jets-separation thresholds, Seshadri constants and higher Gauss-Wahl maps on abelian varieties. https://doi.org/10.1093/imrn%2Frnaf107

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