About

I am a CNRS research scientist at IRIF, Université Paris Cité. I received my PhD from École Normale Supérieure de Paris (ENS) in November 2017, under the supervision of David Pointcheval and Hoeteck Wee. In 2017 – 2019, I was a postdoctoral researcher at Karlsruhe Institute of Technology (KIT), in the team of Dennis Hofheinz.

My main research interests are secure multiparty computation and zero-knowledge proofs (both foundational and practical aspects), as well as the theoretical foundations of cryptography. For an up-to-date list of my publications, you can check my publication page, my dblp profile, or my Google scholar profile. All my publications become available at some point in open access format on the ePrint archive; see the list here. My PhD thesis can be found here.


News

March 2024 I defended my Habilitation à Diriger des Recherches on March 20. An HDR is a French diploma needed to supervize PhD students (without it, a co-supervisor with HDR is required). It proceeds essentially like a second PhD defense. You can find my HDR manuscript here; it provides an overview of secure computation in the correlated randomness model, and a step-by-step introduction to pseudorandom correlation generators, which might be useful for anyone wanting to get into this research area. More information about the defense here.

September 2023: I was awarded an ERC Starting Grant for my project OBELiSC (Overcoming Barriers and Efficiency Limitations in Secure Computation). See here and here for interviews where I explain (in French) the goals of the project, and here for a short abstract (still in French).

June 2023: I was invited to deliver a Spotlight Talk to the 2023 Conference on Information-Theoretic Cryptography (ITC). My talk, titled On Correlated Pseudorandomness, covered pseudorandom correlation generators, their impact on secure computation, and some of the latest advances in the area. You can check the slides here.

April 2022: Our Eurocrypt’22 paper, On Building Fine-Grained One-Way Functions from Strong Average-Case Hardness, has been invited to the Journal of Cryptology. In this work, we prove weak feasibility results and strong barriers for basing extremely limited forms of cryptography on powerful average-case hardness assumptions. Working on this paper has been a long, but thrilling journey with my amazing coauthor, Chris Brzuska.

January 2022: We just completed a book chapter for an upcoming book with Elette Boyle, Niv Gilboa, and Yuval Ishai. It is an up-to-date overview of homomorphic secret sharing, function secret sharing, and some of their many applications (including pseudorandom correlation generators). Check it out!


Resources

This website contains a few posts which might be useful to students in cryptography, gathered in the blog section. It includes in particular:


Students and postdocs

I have the pleasure to advise several amazing PhD students, and I will not be accepting any new PhD requests in the next year or so. However, I have openings for postdocs. Topics of interest include, but are not limited to, secure computation, zero-knowledge proofs, post-quantum cryptography, code-based cryptography, and foundational aspects of cryptography (including black-box separations and connections to learning theory).

If you are interested, send me a mail and consider applying to the openings of the Algorithm and Complexity team of IRIF (the deadline is November 1st, 2023 – but if you missed it, you can still ping me).

Postdocs

  Time period Notes
Sihang Pu Apr. 2024 – current  
Christop Egger Oct. 2022 – current  
Alexander Koch Oct. 2022 – current  
Balthazar Bauer Oct. 2022 – Sep. 2023 Now holding the Chaire de Professeur Junior at UVSQ.
Sven Maier Nov. 2022 – Mar. 2023  

PhD students

  Time period Notes
Bui Dung Oct. 2021 – Secure Computation for Privacy-Preserving Analysis of Medical Data
Clément Ducros Oct. 2021 – Linear Codes for Quantum-Resistant Secure Computation (co-advised with Alain Couvreur)
Eliana Carozza Oct. 2021 – Quantumly hard algebraic problems and their advanced cryptographic applications (co-advised with Antoine Joux)
Ulysse Léchine Oct.2021 – Average-case hardness, entropy, and one-way functions (co-advised with Thomas Seiller)
Pierre Meyer Sep. 2020 – Sep. 2023 Secure computation with constrained communication (co-advised with Elette Boyle). Now postdoc at Aarhus University, supervised by Claudio Orlandi. You can check Pierre’s PhD thesis here.

Master students

  Time period Notes
Alexandros Themelis Apr. 2024 – Sep. 2024 Advanced Post-Quantum Signatures
Bui Dung Mar. 2021 – Aug. 2021 Batch equality tests and secure comparison from pseudorandom correlation generators
Clément Ducros Mar. 2021 – Aug. 2021 Secure computation meets linear-time encodable codes
Michael Reichle Feb. 2020 – Aug. 2020 Efficient range proofs with transparent setup from bounded integer commitments. Michael’s work led to a paper, presented at EUROCRYPT’21. Now postdoc at ETH Zurich under the supervision of Dennis Hofheinz.
Dominik Hartmann Feb. 2019 – Aug. 2020 Compilers for non-interactive zero-knowledge proofs. Dominik’s work led to a paper, presented at CRYPTO’20. Now PhD student at Ruhr Universität Bochum.

Other: visitors, interns, bachelor students

  Time period Status Notes
Willy Quach Feb. 2024 – May 2024 Visting postdoctoral researcher  
Kelsey Melissaris Feb. 2024 – Jun. 2024 Visting postdoctoral researcher  
Nikolas Melissaris Feb. 2024 – Jun. 2024 Visting PhD student  
Sacha Servan-Schreiber Sep. 2023 – March 2024 Visiting PhD student  
Elahe Sadeghi Jun. 2022 – Jul. 2022 Visiting PhD student Elahe’s work led to a paper, presented at EUROCRYPT’23.
Milan Gonzalez-Thauvin May 2021 – Jul. 2021 Internship Constructions of Non-Interactive Zero-Knowledge Proofs: Efficiency and Generality
Maryam Zarezadeh Nov. 2020 – Apr. 2021 Visiting PhD student Non-interactive inner products from LPN. Maryam’s work led to a paper, presented at ASIACRYPT’22.
Elahe Sadeghi Jul. 2020 – Oct. 2020 Internship Statistical ZAPs from group-based assumptions. Elahe’s work led to a paper, presented at TCC’21.
Pierre Meyer Nov. 2020 – Jan. 2020 Internship Breaking the circuit size barrier for secure computation under quasi-polynomial LPN. Pierre’s work led to a paper, presented at EUROCRYPT’21.
Sebastian Faller Oct. 2018 – Feb. 2019 Bachelor Lattice-based implicit zero-knowledge arguments. Now PhD student at ETH Zurich under the supervision of Dennis Hofheinz and Julia Hesse.
Michael Reichle May 2018 – Sep. 2018 Bachelor Non-interactive keyed-verification anonymous credentials. Michael’s work led to a paper, presented at PKC’19. Now postdoc at ETH Zurich under the supervision of Dennis Hofheinz.
Samuel Kopmann Nov. 2017 – Mar. 2018 Bachelor Improved designated-verifier non-interactive zero-knowledge arguments

Program Committees

The list of conferences, workshops, and journals where I served as a member of the program committee (conferences, workshops) or editorial board (journals).

Year Venues
2024 Communications in Cryptology, TCC
2023 CSF, CRYPTO
2022 PKC, CSF, SCN, TCC
2021 EUROCRYPT, IWSEC, WAHC
2020 EUROCRYPT, IWSEC, WAHC
2019 TCC, WAHC
2018 INDOCRYPT