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arXiv · 1609.09592

A note on Iitaka's conjecture $C_{3,1}$ in positive characteristics

Lei Zhang
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Abstract

Let $f:X\to Y$ be a fibration from a smooth projective 3-fold to a smooth projective curve, over an algebraically closed field $k$ of characteristic $p >5$. We prove that if the generic fiber $X_{\eta}$ has big canonical divisor $K_{X_{\eta}}$, then $$\kappa(X)\ge\kappa(Y) + \kappa(X_{\eta}).$$

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Lei Zhang. 2016-09-30. A note on Iitaka's conjecture $C_{3,1}$ in positive characteristics. https://arxiv.org/abs/1609.09592

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