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arXiv · 1508.00484

Weak positivity theorem and Frobenius stable canonical rings of geometric generic fibers

Sho Ejiri
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Abstract

In this paper, we prove the weak positivity theorem in positive characteristic when the canonical ring of the geometric generic fiber $F$ is finitely generated and the Frobenius stable canonical ring of $F$ is large enough. As its application, we show the subadditivity of Kodaira dimensions in some new cases.

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Sho Ejiri. 2015-08-03. Weak positivity theorem and Frobenius stable canonical rings of geometric generic fibers. https://arxiv.org/abs/1508.00484

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