English

Deformations of Compact Calabi--Yau Conifolds

Algebraic Geometry 2025-07-18 v2 Complex Variables Differential Geometry

Abstract

Let XX be a compact normal K\"ahler space whose canonical sheaf is a rank-one free OX\mathcal O_X module and whose singularities are isolated, rational and quasi-homogeneous. We prove then that under a topological hypothesis the obstruction to deforming XX concentrates upon its singularities, generalizing partially the results of Namikawa--Gross. We prove also that under a certain hypothesis the locally trivial deformations of XX are unobstructed.

Keywords

Cite

@article{arxiv.2504.03243,
  title  = {Deformations of Compact Calabi--Yau Conifolds},
  author = {Yohsuke Imagi},
  journal= {arXiv preprint arXiv:2504.03243},
  year   = {2025}
}

Comments

76 pages. I have corrected the errors in the version 1. Theorem 3.4 and Corollary 3.5 were not true as they are. There is a counterexample to Corollary 3.5 with $p=q=0,$ given by the harmonic function $r^{2-2n}.$ Also Lemma 6.5 was not really proved