On the Picard group of low-codimension subvarieties

Enrique Arrondo; Jorge Caravantes

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On the Picard group of low-codimension subvarieties

Enrique Arrondo·Jorge Caravantes

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Abstract

We introduce a method to determine if n-dimensional smooth subvarieties of an ambient space of dimension at most 2n − 2 inherit the Picard group from the ambient space (as it happens when the ambient space is a projective space, according to results of Barth and Larsen). As an application, we give an affirmative answer (up to some mild natural numerical conditions) when the ambient space is a Grassmannian of lines (thus improving results of Barth, Van de Ven and Sommese) or a product of two projective spaces of the same dimension.

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Enrique Arrondo, Jorge Caravantes. 2006-04-18. On the Picard group of low-codimension subvarieties. https://arxiv.org/abs/math/0511267

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