English

A note on supersingular abelian varieties

Number Theory 2017-06-13 v2

Abstract

In this note we show that any supersingular abelian variety is isogenous to a superspecial abelian variety without increasing field extensions. The proof uses minimal isogenies and the Galois descent. We then construct a superspecial abelian variety which not directly defined over a finite field. This answers negatively to a question of the author [J. Pure Appl. Alg., 2013] concerning of endomorphism algebras occurring in Shimura curves. Endomorphism algebras of supersingular elliptic curves over an arbitrary field are also investigated. We correct a main result of the author's paper [Math. Res. Let., 2010].

Keywords

Cite

@article{arxiv.1412.7107,
  title  = {A note on supersingular abelian varieties},
  author = {Chia-Fu Yu},
  journal= {arXiv preprint arXiv:1412.7107},
  year   = {2017}
}

Comments

14 pages. Revise Introduction; add Section 2; erratum to [Math. Res. Let., 2010]= arXiv:0905.0019

R2 v1 2026-06-22T07:41:11.770Z