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arXiv · 1801.04893

On the level of a Calabi-Yau hypersurface

Stiofáin Fordham
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Abstract

Boix-De Stefani-Vanzo defined the notion of level for a smooth projective hypersurface over a finite field in terms of the stabilisation of a chain of ideals previously considered by \`Alvarez-Montaner-Blickle-Lyubeznik, and showed that in the case of an elliptic curve the level is 1 if and only if it is ordinary and 2 otherwise. Here we extend their theorem to the case of Calabi-Yau hypersurfaces by relating their level to the $F$-jumping exponents of Blickle-Musta\c{t}\u{a}-Smith and the Hartshorne-Speiser-Lyubeznik numbers of Musta\c{t}\u{a}-Zhang.

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Stiofáin Fordham. 2018-01-15. On the level of a Calabi-Yau hypersurface. https://arxiv.org/abs/1801.04893

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