English

Unobstructed deformations for singular Calabi-Yau varieties

Algebraic Geometry 2026-02-16 v3

Abstract

Let YY be a compact Gorenstein analytic space with only isolated singularities and trivial dualizing sheaf. A recent paper of Imagi studies the deformation theory of YY in case the singularities of YY are weighted homogeneous and rational and YY is K\"ahler. In this note, assuming that H1(Y;OY)=0H^1(Y;\mathcal{O}_Y) =0, we generalize Imagi's results to the case where the singularities of YY are Du Bois, with no assumption that they be weighted homogeneous, and where the K\"ahler assumption is replaced by the hypothesis that there is a resolution of singularities of YY satisfying the ˉ\partial\bar\partial-lemma. As a consequence, if the singularities of YY are additionally local complete intersections, then the deformations of YY are unobstructed. The log Calabi-Yau and Fano cases are also discussed.

Keywords

Cite

@article{arxiv.2506.09857,
  title  = {Unobstructed deformations for singular Calabi-Yau varieties},
  author = {Robert Friedman},
  journal= {arXiv preprint arXiv:2506.09857},
  year   = {2026}
}

Comments

v.2, 18 pages. More details on the generalized $T^1$ lifting property as well as a discussion of the log Calabi-Yau and Fano cases; v.3, discussion of the generalized Fano case, some references added

R2 v1 2026-07-01T03:11:31.666Z