English

Computing class polynomials for abelian surfaces

Cryptography and Security 2013-12-11 v2 Number Theory

Abstract

We describe a quasi-linear algorithm for computing Igusa class polynomials of Jacobians of genus 2 curves via complex floating-point approximations of their roots. After providing an explicit treatment of the computations in quartic CM fields and their Galois closures, we pursue an approach due to Dupont for evaluating θ\theta- constants in quasi-linear time using Newton iterations on the Borchardt mean. We report on experiments with our implementation and present an example with class number 17608.

Cite

@article{arxiv.1305.4330,
  title  = {Computing class polynomials for abelian surfaces},
  author = {Andreas Enge and Emmanuel Thomé},
  journal= {arXiv preprint arXiv:1305.4330},
  year   = {2013}
}
R2 v1 2026-06-22T00:18:43.258Z