English

Some remarks on Brauer groups of K3 surfaces

Algebraic Geometry 2007-05-23 v2

Abstract

We discuss the geometry of the genus one fibrations associated to an elliptic fibration on a K3 surface. We show that the two-torsion subgroup of the Brauer group of a general elliptic fibration is naturally isomorphic to the two-torsion of the Jacobian of a curve associated to the fibration. We remark that this is related to Recillas' trigonal construction. Finally we discuss the two-torsion in the Brauer group of a general K3 surface with a polarisation of degree two.

Keywords

Cite

@article{arxiv.math/0408006,
  title  = {Some remarks on Brauer groups of K3 surfaces},
  author = {Bert van Geemen},
  journal= {arXiv preprint arXiv:math/0408006},
  year   = {2007}
}

Comments

This replacement has a more general theorem (thm 6.2) on Brauer groups of double covers of rational surfaces. Corrected some typos, updated references. To appear in Advances in Mathematics

R2 v1 2026-07-22T17:08:21.847Z