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arXiv · 1803.01264

Relative linear extensions of sextic del Pezzo fibrations

Takeru Fukuoka
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Abstract

In this paper, we study a sextic del Pezzo fibration over a curve comprehensively. We obtain certain formulae of several basic invariants of such a fibration. We also establish the embedding theorem of such a fibration which asserts that every such a fibration is a relative linear section of a Mori fiber space with the general fiber $(\mathbb{P}^{1})^{3}$ and that with the general fiber $(\mathbb{P}^{2})^{2}$. As an application of this embedding theorem, we classify singular fibers of such a fibrations and answer a question of T. Fujita about existence of non-normal fibers.

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Takeru Fukuoka. 2018-03-03. Relative linear extensions of sextic del Pezzo fibrations. https://arxiv.org/abs/1803.01264

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