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arXiv · 1709.06063

Computing isogenies between Jacobian of curves of genus 2 and 3

Enea Milio
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Abstract

We present a quasi-linear algorithm to compute isogenies between Jacobians of curves of genus 2 and 3 starting from the equation of the curve and a maximal isotropic subgroup of the l-torsion, for l an odd prime number, generalizing the V\'elu's formula of genus 1. This work is based from the paper "Computing functions on Jacobians and their quotients" of Jean-Marc Couveignes and Tony Ezome. We improve their genus 2 case algorithm, generalize it for genus 3 hyperelliptic curves and introduce a way to deal with the genus 3 non-hyperelliptic case, using algebraic theta functions.

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Enea Milio. 2017-09-18. Computing isogenies between Jacobian of curves of genus 2 and 3. https://arxiv.org/abs/1709.06063

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