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arXiv · 1802.03732

Nef anti-canonical divisors and rationally connected fibrations

Sho Ejiri·Yoshinori Gongyo
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Abstract

We study the Iitaka-Kodaira dimension of nef relative anti-canonical divisors. As a consequence, we prove that given a complex projective variety with klt singularities, if the anti-canonical divisor is nef, then the dimension of a general fibre of the maximal rationally connected fibration is at least the Iitaka-Kodaira dimension of the anti-canonical divisor.

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Sho Ejiri, Yoshinori Gongyo. 2018-02-11. Nef anti-canonical divisors and rationally connected fibrations. https://doi.org/10.1112/s0010437x19007383

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