Sam van Gool

News

• September 2025: I am starting a new job as full professor at LMF, Computer Science department, ENS Paris-Saclay.
• August 2025: A new preprint Toposes with enough points as categories of étale spaces, joint with Jérémie Marquès and Umberto Tarantino.
• April 2025: Our paper Learning Weighted Automata over Number Rings, Concretely and Categorically, joint with Quentin Aristote, Daniela Petrişan, and Mahsa Shirmohammadi, was accepted for publication in LICS 2025.
• December 2024: I defended my Habilitation à Diriger des Recherches (HDR) on December 6th, 2024. More information.
• July 2024: Our IJCAR 2024 paper on uniform interpolation, joint with Hugo Férée, Iris van der Giessen, and Ian Shillito, won a best paper award.
• March 2024: The book Topological Duality for Distributive Lattices: Theory and Applications, which I wrote together with Mai Gehrke, is published in its online edition by Cambridge University Press, with print copies available starting April. If you want to "try before you buy", an older, pre-print version is available on ArXiv. (Caution: the ArXiv version does not reflect the latest corrections.)
• In February 2024, we released a Uniform Interpolation Calculator, which lets you compute uniform interpolants in a number of intuitionistic and modal logics. It is based on our verified Coq implementation of the underlying theorems. It's a demo, any feedback on how this can be made more useful for research is welcome!
  Joint work with Hugo Férée, Iris van der Giessen, and Ian Shillito.
• Starting January 2024, I am managing a 4-year research project titled Topology for Types and Terms, funded by the French National Research Agency (ANR) under the Young Researcher (JCJC) scheme.
• December 2023: our paper Deciding Equations in the Time Warp Algebra, with Adrien Guatto, George Metcalfe, and Simon Santschi, was accepted for publication in Logical Methods in Computer Science.
• November 2023: our paper On duality and model theory for polyadic spaces, with Jérémie Marquès, was accepted for publication in Annals of Pure and Applied Logic.

Publications

Teaching

Talks and events

• Duality for automata and regular languages, SGSLPS Summer School, University of Bern, 16-17 June 2025 (tutorial, invited).
• De Bruijn (hyper)graphs and unifiability, GEL seminar, IRIF, 11 June 2025.
• Unification, Stone duality, and de Bruijn graphs (slides), LAC Seminar, Mathematics Department, Università degli Studi di Milano, 6 June 2025.
• On Stone duality and profinite words, Categories for automata and language theory, Dagstuhl seminar 25141, 30 March - 4 April 2025.
• Separation, duality, and profinite lambda-calculus (slides), LMF, ENS Saclay, 21 February 2025.
• Domains and automata in duality-theoretic form (slides), International Symposium on Domain Theory, Qufu, China, 2-5 August 2024 (invited).
• Topology, Algebra, and Categories in Logic, Barcelona, Spain, 1-5 July 2024.
• Theory and Practice of Uniform Interpolation (slides), WoLLiC, Bern, Switzerland, 10-13 June 2024 (invited).
• Solving temporal equations by folding de Bruijn graphs (slides), ATLAS workshop and GT DAAL, Rennes, France, 23-26 April 2024.
• Stone duality and its formalization (slides), Lean for the curious mathematician, Luminy, France, 24-29 March 2024 (invited).
• Profinite monoids as polyadic spaces (slides), AutCat working group, IRIF, 5 March 2024.
• Modal unification and de Bruijn graph homomorphisms, Automata seminar, IRIF, 10 November 2023.
• Modal unification step by step, Workshop on Resources and Co-Resources, University of Cambridge, UK, 17-19 July 2023, first published in UNIF 2023, slides by my co-author Johannes Marti.
• Frames and profinite structures, Formalization of cohomology theories, Banff, Canada, 21-26 May 2023 (mathlib contribution 1, 2, and 3).
• Logic, lattices and profinite structures, Logique à Paris, 9-12 May 2023.
• Formalizing and Computing Propositional Quantifiers, Certified Programs and Proofs, 16-17 January 2023, Boston/online (publication)
• Proaperiodic monoids via saturated models, Structure Meets Power, ICALP Workshop, Paris, 4 July 2022.
• TACL, Coimbra, Portugal, 20-24 June 2022.
• Duality and More workshop, Nice, 16-20 May 2022 (slides).

Collaborations

Service

Links