English

The Picard index of a surface with torus action

Algebraic Geometry 2024-10-28 v2

Abstract

We consider normal rational projective surfaces with torus action and provide a formula for their Picard index, that means the index of the Picard group inside the divisor class group. As an application, we classify the log del Pezzo surfaces with torus action of Picard number one up to Picard index 10,000.

Keywords

Cite

@article{arxiv.2308.08879,
  title  = {The Picard index of a surface with torus action},
  author = {Justus Springer},
  journal= {arXiv preprint arXiv:2308.08879},
  year   = {2024}
}

Comments

30 pages, 3 figures