Cyclic covers: Hodge theory and categorical Torelli theorems
Abstract
Let admit a rectangular Lefschetz decomposition of its derived category, and consider a cyclic cover ramified over a divisor . In a setting not considered by Kuznetsov and Perry, we define a subcategory of the equivariant derived category of which contains, rather than is contained in, . We then show that the equivariant category of the Kuznetsov component of is decomposed into copies of . As an application, we relate with the cohomology of under some numerical assumptions. In particular, we obtain categorical Torelli theorems for the lowest degree prime Fano threefolds of index 1 and 2.
Keywords
Cite
@article{arxiv.2310.13651,
title = {Cyclic covers: Hodge theory and categorical Torelli theorems},
author = {Hannah Dell and Augustinas Jacovskis and Franco Rota},
journal= {arXiv preprint arXiv:2310.13651},
year = {2023}
}
Comments
19 pages. Added a categorical Torelli theorem for prime Fano threefolds of index 2 and degree 1. Slightly weakened the generality assumptions. Other minor changes. Comments welcome!