English

Optimal quotients and surjections of Mordell-Weil groups

Number Theory 2020-01-16 v3

Abstract

Answering a question of Ed Schaefer, we show that if J is the Jacobian of a curve C over a number field, if s is an automorphism of J coming from an automorphism of C, and if u lies in the subring Z[s] of End J and has connected kernel, then it is not necessarily the case that u gives a surjective map from the Mordell-Weil group of J to the Mordell-Weil group of its image.

Keywords

Cite

@article{arxiv.1505.07141,
  title  = {Optimal quotients and surjections of Mordell-Weil groups},
  author = {Everett W. Howe},
  journal= {arXiv preprint arXiv:1505.07141},
  year   = {2020}
}

Comments

Version 2: Improved exposition. Version 3: Corrected a typographical error in a covering map