English

Maximum number of points on intersection of a cubic surface and a non-degenerate Hermitian surface

Algebraic Geometry 2020-02-06 v2

Abstract

In 1991 S{\o}rensen proposed a conjecture for the maximum number of points on the intersection of a surface of degree dd and a non-degenerate Hermitian surface in \PP3(\Fqt)\PP^3(\Fqt). The conjecture was proven to be true by Edoukou in the case when d=2d=2. In this paper, we prove that the conjecture is true for d=3d=3 and q8q \ge 8. We further determine the second highest number of rational points on the intersection of a cubic surface and a non-degenerate Hermitian surface. Finally, we classify all the cubic surfaces that admit the highest and second highest number of points in common with a non-degenerate Hermitian surface. This classifications disproves one of the conjectures proposed by Edoukou, Ling and Xing.

Keywords

Cite

@article{arxiv.1802.06681,
  title  = {Maximum number of points on intersection of a cubic surface and a non-degenerate Hermitian surface},
  author = {Peter Beelen and Mrinmoy Datta},
  journal= {arXiv preprint arXiv:1802.06681},
  year   = {2020}
}