English

Infinitesimal categorical Torelli theorems for Fano threefolds

Algebraic Geometry 2023-05-08 v3

Abstract

Let XX be a smooth Fano variety and Ku(X)\mathcal{K}u(X) the Kuznetsov component. Torelli theorems for Ku(X)\mathcal{K}u(X) says that it is uniquely determined by a polarized abelian variety attached to it. An infinitesimal Torelli theorem for XX says that the differential of the period map is injective. A categorical variant of infinitesimal Torelli theorem for XX says that the morphism H1(X,TX)ηHH2(Ku(X))H^1(X,T_X)\xrightarrow{\eta} HH^2(\mathcal{K}u(X)) is injective. In the present article, we use the machinery of Hochschild (co)homology to relate the three Torelli-type theorems for smooth Fano varieties via a commutative diagram. As an application, we first prove infinitesimal categorical Torelli theorem for a class of prime Fano threefolds. Then we prove a restatement of the Debarre-Iliev-Manivel conjecture infinitesimally.

Keywords

Cite

@article{arxiv.2203.08187,
  title  = {Infinitesimal categorical Torelli theorems for Fano threefolds},
  author = {Augustinas Jacovskis and Xun Lin and Zhiyu Liu and Shizhuo Zhang},
  journal= {arXiv preprint arXiv:2203.08187},
  year   = {2023}
}

Comments

Correct typos, final version, to appear in Journal of Pure and Applied algebra. arXiv admin note: substantial text overlap with arXiv:2108.02946