Deformations of Compact Calabi--Yau and Fano Varieties with Isolated Singularities
Abstract
Let X be a compact log-canonical Kähler n-fold, n≥3, with trivial canonical sheaf and with isolated singularities. We prove that the generic fibres of a semi-universal deformation of X have Du Bois invariant b1,n−2=0 at the singular points. Under a certain topological hypothesis on X the generic fibres have also link invariant l1,n−2=0. If X is a projective log-canonical n-fold, n≥3, with ample anti-canonical sheaf and with isolated singularities then the generic fibres have b1,n−2=l1,n−2=0 (without the topological hypothesis). These are generalizations of recent results of Tenie `Global smoothing of singular Fano and Calabi--Yau varieties' and an older result of Namikawa `Deformation theory of Calabi--Yau threefolds and certain invariants of singularities.'
Related
- Deformations of Calabi--Yau varieties over transversal or crystalline prisms
- Motivic local density of isolated singularities of algebraic varieties
- Invariant complex structures on the Euclidean motion group as deformations of Calabi-Eckmann structures
- Deformations of toric pairs and the smoothing of Batyrev Calabi-Yau threefolds
- The Kuranishi space of joint deformations of Calabi--Yau manifolds and holomorphic vector bundles
BibTeX
@misc{imagi2026deformations,
title = {{Deformations of Compact Calabi--Yau and Fano Varieties with Isolated Singularities}},
author = {Yohsuke Imagi},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.00758},
eprint = {2609.00758},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.00758},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Deformations of Compact Calabi--Yau and Fano Varieties with Isolated Singularities
AU - Yohsuke Imagi
PY - 2026
DA - 2026/09/01
PB - arXiv
DO - 10.48550/arxiv.2609.00758
UR - https://arxiv.org/abs/2609.00758
AB - Let X be a compact log-canonical Kähler n-fold, n≥3, with trivial canonical sheaf and with isolated singularities. We prove that the generic fibres of a semi-universal deformation of X have Du Bois invariant b^1,n−2=0 at the singular points. Under a certain topological hypothesis on X the generic fibres have also link invariant l^1,n−2=0. If X is a projective log-canonical n-fold, n≥3, with ample anti-canonical sheaf and with isolated singularities then the generic fibres have b^1,n−2=l^1,n−2=0 (without the topological hypothesis). These are generalizations of recent results of Tenie `Global smoothing of singular Fano and Calabi--Yau varieties' and an older result of Namikawa `Deformation theory of Calabi--Yau threefolds and certain invariants of singularities.'
ER -