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arXiv · 1611.00416

On the characteristic foliation on a smooth hypersurface in a holomorphic symplectic fourfold

Ekaterina Amerik·Lyalya Guseva
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Abstract

Let $X$ be an irreducible holomorphic symplectic fourfold and $D$ a smooth hypersurface in $X$. It follows from a result by Amerik and Campana that the characteristic foliation (that is the foliation given by the kernel of the restriction of the symplectic form to $D$) is not algebraic unless $D$ is uniruled. Suppose now that the Zariski closure of its general leaf is a surface. We prove that $X$ has a lagrangian fibration and $D$ is the inverse image of a curve on its base.

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Ekaterina Amerik, Lyalya Guseva. 2016-11-01. On the characteristic foliation on a smooth hypersurface in a holomorphic symplectic fourfold. https://arxiv.org/abs/1611.00416

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