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        Home         PQCrypto Seminar         Talks         Research

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Talks

• Making and breaking post-quantum cryptography from elliptic curves (slides), presentation at the DIAMANT Symposium in Utrecht, the Netherlands (April 2023)

• Torsion-point attacks on isogeny-based cryptography, presentation at the algebra and number theory seminar at UCD, Ireland (March 2023)

• Torsion-point attacks on isogeny-based cryptography, presentation at the COGNAC workshop, Luminy, France (February 2023)

• Torsion-point attacks on isogeny-based cryptography, presentation in the Great Western Number Theory Seminar, Oxford, UK (November 2022)

• Torsion-point attacks on isogeny-based cryptology (recording), presentation in the VaNTAGe series, online, USA (November 2022)

• Isogeny-based cryptography: why, how, and what next? (slides), presentation at the Foundations and Applications of Lattice-based Cryptography workshop, Edinburgh, UK (July 2022).

• Transitioning to post-quantum cryptography (slides), panel presentation at the annual CDT Cybersecurity Conference, UCL, UK (June 2022).

• Introduction to elliptic-curve and isogeny-based cryptography (slides), presentation at the Summer School on Real-World Crypto and Privacy, Sibenik, Croatia (June 2022).

• CSIDH, related protocols, and open questions (slides), presentation in the isogeny-based cryptography research workshop, Birmingham, UK (March 2022).

• Isogeny-based cryptography: why, how, and latest news (slides), presentation in the University of Bristol crypto seminar, Bristol, UK (June 2021).

• The even Clifford functor (board pictures), presentation on Section 4.1 of Hein's thesis in the reading group on Hein's thesis at University of Bristol, Bristol, UK (May 2021).

• How to not break SIDH (slides), presentation in the ISG seminar at Royal Holloway, UK (April 2021).

• Bruhat-Tits trees as a tool for isogeny-based cryptography (recording), plenary presentation at the Front Range Number Theory Day in the Front Range area, Colorado, USA (April 2021).

• Post-quantum cryptography (slides), presentation at the Engineering Faculty Research Showcase at the University of Bristol, UK (April 2021).

• Privacy, mass-surveillance, and cryptography (slides), presentation at the Computer Science Society at the University of Bristol, UK (March 2021).

• Bruhat-Tits trees as a tool for isogeny-based cryptography, presentation in the Penn State Algebra and Number Theory Seminar at Penn State University, USA (February 2021).

• Cryptography and quantum computers: where do we stand? (slides), keynote presentation at the ACE-CSR Winter School at the University of Warwick, UK (December 2020).

• Constructing broken SIDH parameters: a tale of De Feo, Jao, and Plut's serendipity (slides), presentation in the Tutte Colloquium at the University of Waterloo, Canada (November 2020).

• Making and breaking post-quantum cryptographic key exchange with elliptic curves (slides), presentation in the maths seminar at IIIT-Delhi, India (October 2020).

• Cryptanalysis of SIDH-style schemes under torsion point attacks, presentation at the Workshop on the Mathematics of Post-Quantum crypto, New Zoomland (July 2020).

• Zooom zoom zoom zoom (slides), presentation in the rump session of Eurocrypt 2020 from my sofa, Bristol, UK (April 2020).

• Quantum attacks on isogeny-based cryptography (slides), presentation in the Quantum Information Theory Seminar at the University of Bristol, UK (April 2020).

• Solving norm equations to attack isogeny-based cryptosystems, presentation in the Linfoot Seminar at the University of Bristol, UK (February 2020).

• Quantum attacks on CSIDH: an overview (slides), presentation in the Simons Institute Quantum Cryptanalysis of Post-Quantum Cryptography Workshop at the University of Berkeley, California, USA (February 2020).

• Cryptography and quantum computers: where do we stand? (slides), presentation in the Computer Science Seminar at the University of Bristol, UK (January 2020).

• How to not break SIDH (slides), presentation in the student seminar at CWI in Amsterdam, The Netherlands (January 2020).

• Non-interactive post quantum key exchange from isogeny graphs of elliptic curves (slides), presentation in the Heilbronn Seminar in Bristol, UK (December 2019).

• Protocols continued (slides), presentation in the Isogeny-based cryptography workshop in Birmingham, UK (September 2019).

• Introduction to isogeny-based cryptography (slides), joint presentation with Lorenz Panny in the SIAM-AG workshop in Bern, Switzerland (July 2019).

• Are pairings really dead? (slides), in the Ei/PSI Seminar at Eindhoven University of Technology, the Netherlands (June 2019).

• How to not break SIDH (slides), a joint talk with Lorenz Panny at CFAIL at Columbia University, New York, USA (June 2019).

• CSIDH: An Efficient Post-Quantum Commutative Group Action (slides), in the SRM Seminar Series at the University of Luxembourg (May 2019).

• CSIDH: An Efficient Post-Quantum Commutative Group Action (slides), in the Mathematics and Statistics Colloquium at USF, USA (April 2019).

• CSIDH: An Efficient Post-Quantum Commutative Group Action (slides), in the Oxford Post-Quantum Cryptography Workshop in Oxford, UK (March 2019).

• Cryptographic applications of isogeny graphs of genus 2 and 3 curves (slides), in the Mathematical foundations of asymmetric cryptography winter school in Aussois, France (March 2019).

• Diffie-Hellman and its applications in a post-quantum world (slides), in Bristol, UK (March 2019).

• CSIDH: An Efficient Post-Quantum Commutative Group Action (slides), in the Cryptography Seminar in Rennes, France (February 2019).

• Constructing Canonical Strategies For Parallel Implementation Of Isogeny Based Cryptography (slides), presentation on behalf of authors Aaron Hutchinson and Koray Karabina at Indocrypt 2018 in New Delhi, India (December 2018).

• A glimpse of hope for pairings (...in a pre-quantum world) (slides), in the Asiacrypt 2018 Rump Session in Brisbane, Australia (December 2018).

• CSIDH: An Efficient Post-Quantum Commutative Group Action, (slides), at ECC 2018 in Osaka, Japan (November 2018).

• A glimpse of hope for pairings (...in a pre-quantum world) (slides), in the ECC 2018 Rump Session in Osaka, Japan (November 2018).

• CSIDH: A post-quantum drop-in replacement for (EC)DH, (slides), course in the ECC Autumn School 2018 in Osaka, Japan (November 2018).

• Isogenizable Discrete Logs, (pdf), talk in the Isogeny Day at KU Leuven, Belgium (October 2018).

• CSIDH: An Efficient Post-Quantum Commutative Group Action, (slides), joint presentation with Lorenz Panny in the Crypto Working Group in Utrecht, the Netherlands (September 2018).

• Isogeny graphs of abelian varieties and applications to the discrete logarithm problem, (pdf), talk in the Oberseminar Algebra/Geometrie in Oldenburg, Germany (April 2018).

• Isogeny graphs of abelian varieties and applications to the discrete logarithm problem, (pdf), talk in the Getaltheorie in Het Vlakkeland-Arithmetique en Plat Pays in Gent, Belgium (March 2018).

• Isogeny graphs of abelian varieties and applications to the discrete logarithm problem, (pdf), talk in the Effective Algebra and Geometry seminar in Rennes, France (January 2018).

• Isogeny graphs of abelian varieties and applications, (pdf), talk in the Luxembourg Number Theory Day in Luxembourg (December 2017).

• Isogeny graphs of abelian varieties and applications to the discrete logarithm problem, (pdf), talk in the Heilbronn Seminar in Bristol, UK (December 2017).

• Counting points on genus 2 curves over finite fields, (pdf), talk in the GAGA Seminar in Utrecht, the Netherlands (November 2017).

• User empowerment for security and privacy in IoT, (pdf), talk in the dcypher Symposium in Utrecht, the Netherlands (October 2017).

• Isogeny graphs, modular polynomials, and point counting for higher genus curves, (pdf), talk in the Number theory seminar at INRIA in Nancy, France (July 2017).

• An introduction to isogeny based crypto, (slides, exercises, solutions), talk in the Post-Quantum crypto summer school in Eindhoven, the Netherlands (June 2017).

• Constructing genus 2 curves over finite fields with a prescribed number of points, (pdf), talk in the DIAMANT Symposium in Breukelen, the Netherlands (June 2017).

• Counting points on genus 2 curves over finite fields, (pdf), talk in the Number Theory Seminar at l'Insitut Fourier, Grenoble, France (May 2017).

• Counting points on genus 2 curves over finite fields, (pdf), talk in the Number Theory Seminar at EPFL, Lausanne, Switzerland (November 2016).

• Studying genus 2 and 3 curves using isogeny graphs and modular polynomials, (pdf), talk in the Algebra Seminar at Universiteit Leiden, the Netherlands (November 2016).

• From conic sections to isogeny graphs, (slides), Colloquium talk at University College Dublin, Ireland (June 2016).

• Modularity of Elliptic Curves over \(\mathbb{Q}\), (pdf), talk in the Elliptic Curves Seminar at Universiteit Leiden, the Netherlands (April 2016).

• Genus 2 curves, join presentation with Martin Djukanovic, Pavel Solomatin and Pinar Kilicer, ALGANT-doc meeting, University of Essen, Germany (March 2016).

• Counting points of Jacobians of Genus 2 curves over large finite fields, progress report on a joint research project at AGC2016, led by Ben Smith and Jaap Top, AGC2016, UCLA, Los Angeles, USA (February 2016).

• Isogeny Graphs, (pdf), talk in the PhD Colloquium at Universiteit Leiden, the Netherlands (October 2015).

• Modular Polynomials for Hilbert Modular Forms, (poster), presentation of a poster at Modular Forms and Curves of Low Genus: Computational Aspects, ICERM, Providence, USA (September/October 2015).

• The theory of canonical lifts, (pdf), Universiteit Leiden, the Netherlands (July 2015).

• The Galois representation associated to modular forms (Part I), (pdf), Universiteit Leiden, the Netherlands (May 2015).

• Generalising a result of Elkies-Mcmullen, presentation of a group research project at Arizona Winter School led by Ravi Vakil, (project (4) from the Course and project outline), Arizona Winter School, University of Arizona, USA (March 2015).

• Isogeny Graphs in Genus 2, (pdf), ALGANT-doc meeting, University of Regensburg, Germany (March 2015).

• Etale coverings and the Structure of Hom(X,X), (follows pages 167-182 of 'Abelian Varieties' by David Mumford (Second Edition)), Reading group on Mumford's 'Abelian Varieties', IMB, Université de Bordeaux, France (December 2014).

• An algorithm for computing Hilbert modular varieties (pdf), LFANT Seminar, IMB, Université de Bordeaux, France (September 2014).

• Isogeny Pancakes and computing Hilbert modular varieties, Junior Number Theory Seminar, University of Oxford, UK (June 2014).

• Generalizing the Bertini smoothness theorem, presentation of a group research project at Arizona Winter School led by Bjorn Poonen, (project (1) from the Course and project outline), Arizona Winter School, University of Arizona, USA (March 2014).

• Endomorphisms of Abelian varieties and their representations, (pdf), seminar on Complex Multiplication, Universiteit Leiden, the Netherlands (October 2013).

• Galois categories, (follows Section 3 of Galois theory for schemes), The Etale Fundamental Group, Universiteit Leiden, the Netherlands (October 2013).

• Elliptic curves and jacobians of curves of genus 2, talk on master thesis supervised by Prof. E. Victor Flynn, University of Oxford, UK (April 2013).