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Explicit Noether-Lefschetz for arbitrary threefolds

Angelo Felice Lopez·Catriona Maclean
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Abstract

We study the Noether-Lefschetz locus of a very ample line bundle L on an arbitrary smooth threefold Y. Building on results of Green, Voisin and Otwinowska, we give explicit bounds, depending only on the Castelnuovo-Mumford regularity properties of L, on the codimension of the components of the Noether-Lefschetz locus of |L|.

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Angelo Felice Lopez, Catriona Maclean. 2005-07-18. Explicit Noether-Lefschetz for arbitrary threefolds. https://arxiv.org/abs/math/0507362

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