English

Kuznetsov components ans transcendental motives of cubic fourfolds

Algebraic Geometry 2026-05-15 v1

Abstract

Let X\C5X \subset \P^5_{\C} be a smooth cubic fourfold.The Kuznetsov component \sAX\sA_X is contained in the derived category Db(X)D^b(X) and the transcendental motive t(X)t(X) is contained in the category of Chow motives \sMrat(\C))\sM_{rat}(\C)). If XX and YY are {\it Fourier -Mukai partners} and hence the categories \sAX\sA_X and \sAY\sA_Y are equivalent, then their transcendental motives t(X)t(X) and t(Y)t(Y) are isomorphic. The aim of this note is to consider families of special cubic fourfolds XX with their FM-partners YY and to give an explicit description of the isomorphism between the transcendental motives, in the case XX and YY are rational and when they are conjecturally irrational. We also prove that ,for special cubic fourfolds XX in countably many Hassett divisors, with a symplectic automorphism of order 3, there exists another special cubic fourfold YY, an equivalence of categories \sAXG\sAY\sA^G_X \simeq \sA_{Y}, where \sAXG\sA^G_X is the equivariant Kuznetsov component, and an isomorphism t(X)t(Y)t(X) \simeq t(Y).

Keywords

Cite

@article{arxiv.2605.14763,
  title  = {Kuznetsov components ans transcendental motives of cubic fourfolds},
  author = {Claudio Pedrini},
  journal= {arXiv preprint arXiv:2605.14763},
  year   = {2026}
}