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  • This session has been presented January 10, 2020.

Description

  • Speaker

    Jean Kieffer - Université Bordeaux 1

Given two l-isogenous elliptic curves, a well-known algorithm of Elkies uses modular polynomials to compute this isogeny explicitly. In this work, we generalize his ideas to Jacobians of genus 2 curves. Our algorithms works for both l-isogenies and (in the RM case) cyclic isogenies, and uses Siegel or Hilbert type modular equations respectively. This has applications for point counting in genus 2: SEA-style methods are now available.<br/> lien: http://desktop.visio.renater.fr/scopia?ID=726145***4969&autojoin

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