Computing square-free polarized abelian varieties over finite fields

Abstract

We give algorithms to compute isomorphism classes of ordinary abelian varieties defined over a finite field ${\mathbb{F}}_q$ whose characteristic polynomial (of Frobenius) is square-free and of abelian varieties defined over the prime field ${\mathbb{F}}_p$ whose characteristic polynomial is square-free and does not have real roots. In the ordinary case we are also able to compute the polarizations and the group of automorphisms (of the polarized variety) and, when the polarization is principal, the period matrix.

accepted by Math. Comp. major revision: added computation of the group of points; examples have been exported on the repo