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arXiv · 1203.6323

On deformations of Q-Fano threefolds

Taro Sano
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Abstract

We study the deformation theory of a Q-Fano 3-fold with only terminal singularities. First, we show that the Kuranishi space of a Q-Fano 3-fold is smooth. Second, we show that every Q-Fano 3-fold with only "ordinary" terminal singularities is Q-smoothable, that is, it can be deformed to a Q-Fano 3-fold with only quotient singularities. Finally, we prove Q-smoothability of a Q-Fano 3-fold assuming the existence of a Du Val anticanonical element. As an application, we get the genus bound for primary Q-Fano 3-folds with Du Val anticanonical elements.

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Taro Sano. 2014-10-29. On deformations of Q-Fano threefolds. https://arxiv.org/abs/1203.6323

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