English

Abelian varieties over large algebraic fields with infinite torsion

Number Theory 2010-12-14 v1

Abstract

Let A be an abelian variety of positive dimension defined over a number field K and let Kbar be a fixed algebraic closure of K. For each element sigma of the absolute Galois group Gal(Kbar/K), let Kbar(sigma) be the fixed field of sigma in Kbar. We shall prove that the torsion subgroup of A(Kbar(sigma)) is infinite for all sigma in Gal(Kbar/K) outside of some set of Haar measure zero. This proves the number field case of a conjecture of Geyer and Jarden from 1978.

Keywords

Cite

@article{arxiv.1012.2477,
  title  = {Abelian varieties over large algebraic fields with infinite torsion},
  author = {David Zywina},
  journal= {arXiv preprint arXiv:1012.2477},
  year   = {2010}
}
R2 v1 2026-06-21T16:57:06.598Z