Valerie Gilchrist

(she/her)

Email: valerie.gilchrist@ulb.be // CV: here

I am a PhD student at Université Libre de Bruxelles, working with Christophe Petit. I do research mostly in isogeny-based cryptography, either looking for algorithmic improvements to systems or investigating their security claims.

I did a Masters of Mathematics at the University of Waterloo with David Jao. My thesis was about using SQISign in an adaptor signature.

Publications and preprints

"Attacking trapdoors from matrix products." Thomas Decru, Tako Boris Fouotsa, Paul Frixons, Valerie Gilchrist, Christophe Petit. Communications in Cryptology, Volume 1, Issue 3 (2024). eprint.

"Solving the Tensor Isomorphism Problem for special orbits with low rank points: Cryptanalysis and repair of an Asiacrypt 2023 commitment scheme." Valerie Gilchrist, Laurane Marco, Christophe Petit, Gang Tang. CRYPTO 2024. eprint.

"Fast and Frobenius: Rational Isogeny Evaluation over Finite Fields." Gustavo Banegas, Valerie Gilchrist, Anaelle Le Devehat, Benjamin Smith. LatinCrypt 2023. eprint.

"Efficient supersingularity testing over F_p and CSIDH key validation." Gustavo Banegas, Valerie Gilchrist, Benjamin Smith. MathCrypt 2022. eprint. Video from MathCrypt. Slides.

"An Isogeny-Based Adaptor Signature Using SQISign." (Masters thesis). Valerie Gilchrist. UWSpace 2022. pdf. Slides.

Upcoming Talks

  • "Attacking trapdoors from matrix products" at ArcticCrypt (August 2025).

    • Conferences and Invited Talks

  • "Solving the Tensor Isomorphism Problem for special orbits" at the University of Rennes, cryptography seminar (November 2024). Slides.
  • "Solving the Tensor Isomorphism Problem for special orbits" at the Universté Libre de Bruxelles, security seminar (May 2024).
  • Seminar talks at the University of Auckland, algebra group and graduate student group (March 2024).
  • "Computing rational isogenies from irrational kernel generators" at LatinCrypt (October 2023).
  • "Efficient supsersingularity testing" at SIAM Conference: Algebraic Geometry (July 2023).
  • "The State of Post-Quantum Cryptography" at Cyberus (July 2023). Slides.
  • "Computing rational isogenies from irrational kernel generators" at Isogeny Club (April 2023). Video. Slides.
  • "Efficient supsersingularity testing over F_p and CSIDH key validation" at Isogeny Days (September 2022). Video. Slides.
  • "Efficient supsersingularity testing over F_p and CSIDH key validation" at MathCrypt (August 2022).
  • "SAS: an adaptor signature from isogenies" at Inria Saclay (July 2022).


    See @fjotographie for more cool pictures (not of me).