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arXiv · 1302.3189

Lefschetz for local Picard groups

Bhargav Bhatt·Aise Johan de Jong
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Abstract

We prove a strengthening of the Grothendieck-Lefschetz hyperplane theorem for local Picard groups conjectured by Koll\'ar. Our approach, which relies on acyclicity results for absolute integral closures, also leads to a restriction theorem for higher rank bundles on projective varieties in positive characteristic.

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Bhargav Bhatt, Aise Johan de Jong. 2013-02-13. Lefschetz for local Picard groups. https://arxiv.org/abs/1302.3189

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