Academic Journal

Versal dg deformation of Calabi–Yau manifolds

Bibliographic Details
Title: Versal dg deformation of Calabi–Yau manifolds
Authors: Hayato Morimura
Source: Journal of Algebra. 697:243-311
Publication Status: Preprint
Publisher Information: Elsevier BV, 2026.
Publication Year: 2026
Subject Terms: 14J32, FOS: Mathematics, 0101 mathematics, Algebraic Geometry, 01 natural sciences, Algebraic Geometry (math.AG)
Description: We prove the equivalence of the deformation theory for a higher dimensional Calabi--Yau manifold and that for its dg category of perfect complexes by giving a natural isomorphism of the deformation functors. As a consequence, the dg category of perfect complexes on a versal deformation of the original manifold provides a versal Morita deformation of its dg category of perfect complexes. Besides the classical uniqueness up to étale neiborhood of the base, we prove another sort of uniqueness of versal Morita deformations. Namely, given a pair of derived-equivalent higher dimensional Calabi--Yau manifolds, the dg categories of perfect complexes of their algebraic deformations over a common base, which always exist, become quasi-equivalent close to effectivizations. Then the base change along the corresponding first order approximation yields quasi-equivalent versal Morita deformations. We introduce the generic fiber of the versal Morita deformation as a Drinfeld quotient, which is quasi-equivalent to the dg category of perfect complexes on the generic fiber of the versal deformation.
47 pages; v3: Corrected errors in Section 6. Minor changes here and there
Document Type: Article
Language: English
ISSN: 0021-8693
DOI: 10.1016/j.jalgebra.2026.02.031
DOI: 10.48550/arxiv.2111.11778
Access URL: https://arxiv.org/abs/2111.11778
http://arxiv.org/abs/2111.11778
Rights: CC BY
Accession Number: edsair.doi.dedup.....9052bc5e8097be6d3d7f8fd15967c033
Database: OpenAIRE
Description
ISSN:00218693
DOI:10.1016/j.jalgebra.2026.02.031