English

Real structures on rational surfaces and automorphisms acting trivially on Picard groups

Algebraic Geometry 2015-12-01 v5

Abstract

In this article, we prove that any complex smooth rational surface XX which has no automorphism of positive entropy has a finite number of real forms (this is especially the case if XX cannot be obtained by blowing up PC2\mathbb P^2_{\mathbb C} at r10r\geq 10 points). In particular, we prove that the group Aut#X\mathrm{Aut}^{\#}X of complex automorphisms of XX which act trivially on the Picard group of XX is a linear algebraic group defined over R\mathbb R.

Keywords

Cite

@article{arxiv.1409.3490,
  title  = {Real structures on rational surfaces and automorphisms acting trivially on Picard groups},
  author = {Mohamed Benzerga},
  journal= {arXiv preprint arXiv:1409.3490},
  year   = {2015}
}

Comments

Minor changes. To appear in Mathematische Zeitschrift

R2 v1 2026-06-22T05:54:38.162Z