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arXiv · 2410.16974

Density of Noether-Lefschetz loci for surfaces in Fano and Calabi-Yau threefolds

Edoardo Mason
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Abstract

In this paper we provide applications of general results of Baldi-Klingler-Ullmo and Khelifa-Urbanik on the geometry of the Hodge locus associated to an integral polarized variation of Hodge structures to the case of Noether-Lefschetz loci for families of surfaces. In particular, we consider the family of surfaces in the linear system of a sufficiently ample line bundle on a smooth projective threefold $Y$, in case $Y$ is a Fano or a Calabi-Yau threefold, and we discuss the different behaviour of the union of the general, respectively exceptional, components of its Noether-Lefschetz locus.

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Edoardo Mason. 2024-10-22. Density of Noether-Lefschetz loci for surfaces in Fano and Calabi-Yau threefolds. https://arxiv.org/abs/2410.16974

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