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arXiv · 1911.10385

Grothendieck--Lefschetz for ample subvarieties

Tommaso de Fernex·Chung Ching Lau
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Abstract

We establish a Grothendieck--Lefschetz theorem for smooth ample subvarieties of smooth projective varieties over an algebraically closed field of characteristic zero and, more generally, for smooth subvarieties whose complement has small cohomological dimension. A weaker statement is also proved in a more general context and in all characteristics. Several applications are included.

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Tommaso de Fernex, Chung Ching Lau. 2019-11-23. Grothendieck--Lefschetz for ample subvarieties. https://arxiv.org/abs/1911.10385

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