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arXiv · 1405.2415

$\mathbb{Q}$-Fano threefolds with three birational Mori fiber structures

Takuzo Okada
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Abstract

In this paper we give first examples of $\mathbb{Q}$-Fano threefolds whose birational Mori fiber structures consist of exactly three $\mathbb{Q}$-Fano threefolds. These examples are constructed as weighted hypersurfaces in a specific weighted projective space. We also observe that the number of birational Mori fiber structures does not behave upper semi-continuously in a family of $\mathbb{Q}$-Fano threefolds.

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Takuzo Okada. 2014-05-10. $\mathbb{Q}$-Fano threefolds with three birational Mori fiber structures. https://arxiv.org/abs/1405.2415

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