English

Splitting Brauer classes using the universal Albanese

Algebraic Geometry 2018-11-14 v3 Number Theory Rings and Algebras

Abstract

We prove that every Brauer class over a field splits over a torsor under an abelian variety. If the index of the class is not congruent to 2 modulo 4, we show that the Albanese variety of any smooth curve of positive genus that splits the class also splits the class, and there exist many such curves splitting the class. We show that this can be false when the index is congruent to 2 modulo 4, but adding a single genus 1 factor to the Albanese suffices to split the class.

Keywords

Cite

@article{arxiv.1805.12566,
  title  = {Splitting Brauer classes using the universal Albanese},
  author = {Wei Ho and Max Lieblich},
  journal= {arXiv preprint arXiv:1805.12566},
  year   = {2018}
}

Comments

11 pages, references and acknowledgments updated, comments welcome at any time

R2 v1 2026-06-23T02:15:00.470Z