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arXiv · 1607.00840

Cylinders in del Pezzo fibrations

Adrien Dubouloz·Takashi Kishimoto
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Abstract

We show that a del Pezzo fibration $\pi$ : V $\rightarrow$ W of degre d contains a vertical open cylinder, that is, an open subset whose intersection with the generic fiber of $\pi$ is isomorphic to $Z\times\mathbb{A}_{K}^{1}$ for some quasi-projective variety Z defined over the function field K of W , if and only if d $\ge$ 5 and $\pi$ : V $\rightarrow$ W admits a rational section. We also construct twisted cylinders in total spaces of threefold del Pezzo fibrations $\pi$ : V $\rightarrow$ P 1 of degree d $\le$ 4.

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Adrien Dubouloz, Takashi Kishimoto. 2016-07-04. Cylinders in del Pezzo fibrations. https://arxiv.org/abs/1607.00840

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