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Deformations of weak $ℚ$ -Fano $3$ -folds

Faculty of Science, Department of Mathematics, Kobe University, 1-1, Rokkodai, Nada-ku, Kobe 657-8501, Japan

E-mail Address: tarosano@math.kobe-u.ac.jp

https://doi.org/10.1142/S0129167X18500490Cited by:1 (Source: Crossref)

Abstract

We prove that a weak $ℚ$ -Fano $3$ -fold with terminal singularities has unobstructed deformations. By using this result and computing some invariants of a terminal singularity, we provide two results on global deformation of a weak $ℚ$ -Fano $3$ -fold. We also treat a stacky proof of the unobstructedness of deformations of a $ℚ$ -Fano $3$ -fold.

Keywords:

AMSC: 14B07, 14J30, 14J45, 14B15

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