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Cone Theorem via Deligne-Mumford stacks

Jiun-Cheng Chen·Hsian-Hua Tseng
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Abstract

We prove the cone theorem for varieties with LCIQ singularities using deformation theory of stable maps into Deligne-Mumford stacks. We also obtain a sharper bound on $-(K_X+D)$-degree of $(K_X+D)$-negative extremal rays for projective $\QQ$-factorial log terminal threefold pair $(X,D)$.

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Jiun-Cheng Chen, Hsian-Hua Tseng. 2005-05-03. Cone Theorem via Deligne-Mumford stacks. https://arxiv.org/abs/math/0505043

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