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http://dx.doi.org/10.4134/JKMS.j190810

A SUFFICIENT CONDITION FOR A TORIC WEAK FANO 4-FOLD TO BE DEFORMED TO A FANO MANIFOLD  

Sato, Hiroshi (Department of Applied Mathematics Faculty of Sciences Fukuoka University)
Publication Information
Journal of the Korean Mathematical Society / v.58, no.5, 2021 , pp. 1081-1107 More about this Journal
Abstract
In this paper, we introduce the notion of toric special weak Fano manifolds, which have only special primitive crepant contractions. We study their structure, and in particular completely classify smooth toric special weak Fano 4-folds. As a result, we can confirm that almost every smooth toric special weak Fano 4-fold is a weakened Fano manifold, that is, a weak Fano manifold which can be deformed to a Fano manifold.
Keywords
Toric manifolds; weak Fano manifolds; deformation theory;
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