Toward the classification of threefold extremal contractions with one-dimensional fibers

Shigefumi Mori; Yuri Prokhorov

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arXiv · 2410.03165

Toward the classification of threefold extremal contractions with one-dimensional fibers

Shigefumi Mori·Yuri Prokhorov

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Abstract

An extremal curve germ is a germ of a threefold $X$ with terminal singularities along a connected reduced complete curve~$C$ such that there exists a $K_X$-negative contraction $f : X \to Z$ with~$C$ being a fiber. We give a rough classification of extremal curve germs with reducible central curve~$C$.

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Shigefumi Mori, Yuri Prokhorov. 2024-10-04. Toward the classification of threefold extremal contractions with one-dimensional fibers. https://arxiv.org/abs/2410.03165

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