English

Surfaces on the Severi line

Algebraic Geometry 2022-08-09 v1

Abstract

Let S be a minimal complex surface of general type and of maximal Albanese dimension; by the Severi inequality one has KS24χ(OS)K^2_S\geq 4\chi(\mathcal O_S). We prove that the equality KS2=4χ(OS)K^2_S=4\chi(\mathcal O_S) holds if and only if q(S):=h1(OS)=2q(S):= h^1(\mathcal O_S)=2 and the canonical model of SS is a double cover of the Albanese surface branched on an ample divisor with at most negligible singularities.

Keywords

Cite

@article{arxiv.1504.06590,
  title  = {Surfaces on the Severi line},
  author = {Miguel Ángel Barja and Rita Pardini and Lidia Stoppino},
  journal= {arXiv preprint arXiv:1504.06590},
  year   = {2022}
}

Comments

13 pages

R2 v1 2026-06-22T09:22:18.256Z