English

Enriques' characterization of Abelian surfaces in positive characteristic

Algebraic Geometry 2026-05-20 v1

Abstract

Extending Enriques' characterization to algebraically closed fields of characteristic p7p \geq 7, we show that every smooth projective surface XX with h1(X,OX)=2h^1(X, \mathcal{O}_X) = 2 and p1(X)=p2(X)=1p_1(X) = p_2(X) = 1 is birational to an Abelian surface. This characterization fails if p5p \leq 5, and we give a sharp alternative.

Keywords

Cite

@article{arxiv.2605.20010,
  title  = {Enriques' characterization of Abelian surfaces in positive characteristic},
  author = {Jefferson Baudin and Gebhard Martin},
  journal= {arXiv preprint arXiv:2605.20010},
  year   = {2026}
}

Comments

12 pages, comments welcome