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arXiv · 2004.01036

Subadjunction for quasi-log canonical pairs and its applications

Osamu Fujino
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Abstract

We establish a kind of subadjunction formula for quasi-log canonical pairs. As an application, we prove that a connected projective quasi-log canonical pair whose quasi-log canonical class is anti-ample is simply connected and rationally chain connected. We also supplement the cone theorem for quasi-log canonical pairs. More precisely, we prove that every negative extremal ray is spanned by a rational curve. Finally, we treat the notion of Mori hyperbolicity for quasi-log canonical pairs.

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Osamu Fujino. 2020-04-01. Subadjunction for quasi-log canonical pairs and its applications. https://arxiv.org/abs/2004.01036

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