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arXiv · 2102.11986

Cone theorem and Mori hyperbolicity

Osamu Fujino
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Abstract

We discuss the cone theorem for quasi-log schemes and the Mori hyperbolicity. In particular, we establish that the log canonical divisor of a Mori hyperbolic projective normal pair is nef if it is nef when restricted to the non-lc locus. This answers Svaldi's question completely. We also treat the uniruledness of the degenerate locus of an extremal contraction morphism for quasi-log schemes. Furthermore, we prove that every fiber of a relative quasi-log Fano scheme is rationally chain connected modulo the non-qlc locus.

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Osamu Fujino. 2021-02-23. Cone theorem and Mori hyperbolicity. https://arxiv.org/abs/2102.11986

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