Table of contents

  • This session has been presented April 15, 2005.

Description

  • Speaker

    Johan Bosma - Leiden University

We will describe how we are implementing Edixhoven's method for computing polynomials for the mod l Galois representations associated to modular forms. The computations are done in MAGMA, using modular symbols and numerical analysis. Recently, we have computed such polynomials for the mod 13 representation associated to Delta, the discriminant modular form of weight 12. In that case, we work with the modular curve X_1(13), which is of genus 2, and the polynomials have degrees 14 and 168.

Next sessions

  • Endomorphisms via Splittings

    • April 10, 2026 (13:45 - 14:45)

    • IRMAR - Université de Rennes - Campus Beaulieu Bat. 22, RDC, Rennes - Amphi Lebesgue

    Speaker : Min-Yi Shen - No Affiliation

    One of the fundamental hardness assumptions underlying isogeny-based cryptography is the problem of finding a non-trivial endomorphism of a given supersingular elliptic curve. In this talk, we show that the problem is related to the problem of finding a splitting of a principally polarised superspecial abelian surface. In particular, we provide formal security reductions and a proof-of-concept[…]
    • Cryptography

  • Schéma de signature à clé publique : Frobénius-UOV

    • May 29, 2026 (13:45 - 14:45)

    • IRMAR - Université de Rennes - Campus Beaulieu Bat. 22, RDC, Rennes - Amphi Lebesgue

    Speaker : Gilles Macario-Rat - Orange

    L'exposé présente un schéma de signature à clé publique post-quantique inspiré du schéma UOV et introduisant un nouvel outil : les formes de Frobénius. L'accent est mis sur le rôle et les propriétés des formes de Frobénius dans ce nouveau schéma : la simplicité de description, la facilité de mise en oeuvre et le gain inédit sur les tailles de signature et de clé qui bat RSA-2048 au niveau de[…]
Show previous sessions