English

A census of cubic fourfolds over $\mathbb{F}_2$

Algebraic Geometry 2023-06-19 v1 Number Theory

Abstract

We compute a complete set of isomorphism classes of cubic fourfolds over F2\mathbb{F}_2. Using this, we are able to compile statistics about various invariants of cubic fourfolds, including their counts of points, lines, and planes; all zeta functions of the smooth cubic fourfolds over F2\mathbb{F}_2; and their Newton polygons. One particular outcome is the number of smooth cubic fourfolds over F2\mathbb{F}_2, which we fit into the asymptotic framework of discriminant complements. Another motivation is the realization problem for zeta functions of K3K3 surfaces. We present a refinement to the standard method of orbit enumeration that leverages filtrations and gives a significant speedup. In the case of cubic fourfolds, the relevant filtration is determined by Waring representation and the method brings the problem into the computationally tractable range.

Keywords

Cite

@article{arxiv.2306.09908,
  title  = {A census of cubic fourfolds over $\mathbb{F}_2$},
  author = {Asher Auel and Avinash Kulkarni and Jack Petok and Jonah Weinbaum},
  journal= {arXiv preprint arXiv:2306.09908},
  year   = {2023}
}

Comments

21 pages, 6 figures

R2 v1 2026-06-28T11:07:18.716Z