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arXiv · 1210.0421

Bogomolov-Sommese vanishing on log canonical pairs

Patrick Graf
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Abstract

Let (X, D) be a projective log canonical pair. We show that for any natural number p, the sheaf (Omega_X^p(log D))^** of reflexive logarithmic p-forms does not contain a Weil divisorial subsheaf whose Kodaira-Iitaka dimension exceeds p. This generalizes a classical theorem of Bogomolov and Sommese. In fact, we prove a more general version of this result which also deals with the orbifoldes g\'eom\'etriques introduced by Campana. The main ingredients to the proof are the extension theorem of Greb-Kebekus-Kov\'acs-Peternell, a new version of the Negativity lemma, the Minimal Model Program, and a residue map for symmetric differentials on dlt pairs. We also give an example showing that the statement cannot be generalized to spaces with Du Bois singularities. As an application, we give a Kodaira-Akizuki-Nakano-type vanishing result for log canonical pairs which holds for reflexive as well as for K\"ahler differentials.

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Patrick Graf. 2012-10-01. Bogomolov-Sommese vanishing on log canonical pairs. https://doi.org/10.1515/crelle-2013-0031

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