English

Ordinary abelian varieties: isogeny graphs and polarizations

Number Theory 2026-01-30 v1

Abstract

Given an integer DD and an ordinary isogeny class of abelian varieties defined over a finite field Fq\mathbb{F}_q with commutative Fq\mathbb{F}_q-endomorphism algebra, we provide algorithms for computing all isogenies of degree dividing DD and polarizations of degree dividing DD. We discuss phenomena that arise for higher dimension abelian varieties but not elliptic curves, bounds on the diameter of the graph of minimal isogenies, and decompositions of isogeny graphs into orbits for the Picard group of the Frobenius order.

Keywords

Cite

@article{arxiv.2601.20979,
  title  = {Ordinary abelian varieties: isogeny graphs and polarizations},
  author = {Edgar Costa and Taylor Dupuy and Stefano Marseglia and David Roe and Christelle Vincent},
  journal= {arXiv preprint arXiv:2601.20979},
  year   = {2026}
}
R2 v1 2026-07-01T09:24:33.410Z