Nicolas Behr

Nicolas Behr

CNRS Researcher in Computer Science

Université Paris Cité, CNRS, IRIF, France

Biography

I am a CNRS researcher in theoretical computer science with Institut de recherche en informatique fondamentale (IRIF), the Computer Science laboratory of Université Paris Cité, where I am a member of the Preuves, programmes et systèmes group. Previously, I have been a Short-Term Fellow at CRI Paris in spring and summer of 2020, working on the development of tracelet-analysis algorithms for the biochemistry platform Kappa and for the organo-chemistry platform MØD. I previously held a Marie Skłodowska-Curie Individual Fellowship (2017-2019), working in the field of theoretical computer science at IRIF, Université Paris Diderot. The aim of my project with Jean Krivine (IRIF) consisted in developing extensions of my rule-algebraic framework to restricted variants of rewriting and to the biochemical reaction language Kappa. I am also frequently to be found at the LPTMC of the UPMC/Sorbonne/Paris 06, working with Gérard H.E. Duchamp (Paris 13) and Karol A. Penson (Paris 6) on topics in combinatorics. My previous positions include a Postdoc position with Vincent Danos at ENS Paris and at University of Edinburgh (2014-2017) and a Postdoc position in mathematical physics with Anatoly Konechny at Heriot-Watt University in Edinburgh (2011-2014).

I am the Scientific Coordinator of the ANR project CoREACT - Coq-based Rewriting: towards Executable Applied Category Theory (2023 - 2027).

Together with Andrea Corradini, Reiko Heckel and Jean Krivine, I am organizing the GReTA - Graph Transformation Theory and Applications online seminar series - see www.irif.fr/~greta for more information and seminar announcements.

News

I am delighted to report that our ANR project CoREACT (“Coq-based Rewriting: towards Executable Applied Category Theory”) has been selected for funding! The project will start in March 2023, and you can watch an overview of the project goals and research ideas here and here. The kick-off meeting will take place on April 19, 2023 at IRIF, Université Paris Cité.

Professional service 2023: PC member of CALCO 2023 and ICGT 2023; managing guest editor for the JLAMP ICGT 2022 Special Issue

I have been invited to give a talk at the “Category Theory at Work in Computational Mathematics and Theoretical Informatics” meeting at the Lie-Størmer Center, a newly founded Norwegian research center for fundamental structures in computational and pure mathematics.

Selected Talks & Activities

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20/11 - 22/11/2024 Combinatorics and Arithmetic for Physics: special days workshop (invited talk), Institut des Hautes Études Scientifiques (IHÉS), Bures sur Yvette, France
10 - 11/07/2024 17th International Conference on Graph Transformation (ICGT 2024) (talk), Enschede, The Netherlands
24 - 25/06/2024 Journées PPS (talk), IRIF, Université Paris Cité, Paris, France
27 - 29/05/2024 Hypermatrix Workshop 2024 (talk), LPTMC, Sorbonne Université, Paris, France
21/05/2024 ANR CoREACT seminar (participant), online
16 - 17/05/2024 Quo Transformes? workshop (invited talk), University of Pisa, Italy
11 - 13/03/2024 ANR CoREACT General Meeting (participant), ENS Lyon, France
21 - 26/01/2024 Higher Segal Spaces and their Applications to Algebraic K-Theory, Hall Algebras, and Combinatorics workshop (invited participant), Banff International Research Station, Calgary, Canada
15/12/2023 MDENet France Workshop 2023 (participant), LIP6, Sorbonne Université, Paris, France
15/11 - 17/11/2023 Combinatorics and Arithmetic for Physics: special days workshop (participant), Institut des Hautes Études Scientifiques (IHÉS), Bures sur Yvette, France

Videos

Software

Based upon joint work with Reiko Heckel and Maryam Ghaffari Saadat (University of Leicester), I am developing the ReSMT Python package, which aims to implement rewriting-theoretic concepts via utilizing the Microsoft Z3 theorem prover as the computational core. At present (v. 0.0.3), the package covers typed directed multigraphs (TDGs) with structural constraints as its base datatype, with some of the key operations implemented including the search for partial overlaps of TDGs modulo structural constraints formulated via forbidden pattern non-embedding assertions.

Interests
  • Stochastic rewriting systems
  • Combinatorics of dynamical systems
  • Moment bisimulations
  • Tracelets
Education
  • PhD in Mathematical Physics, 2012

    Max Planck Institute for Gravitational Physics Golm and Humboldt University Berlin

  • Diploma in Mathematical Physics, 2008

    Max Planck Institute for Gravitational Physics Golm and Humboldt University Berlin

Preprints and Publications

(2023). Fundamentals of Compositional Rewriting Theory. In: Journal of Logical and Algebraic Methods in Programming, Volume 135, 2023.

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(2023). Convolution Products on Double Categories and Categorification of Rule Algebras. In: 8th International Conference on Formal Structures for Computation and Deduction (FSCD 2023), Leibniz International Proceedings in Informatics (LIPIcs).

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(2022). Tracelet Hopf algebras and decomposition spaces. In Kohei Kishida: Proceedings of the Fourth International Conference on Applied Category Theory (ACT 2021), Cambridge, United Kingdom, 12-16th July 2021, Electronic Proceedings in Theoretical Computer Science 372, pp. 323–337..

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(2021). Rewriting theory for the life sciences: A unifying theory of CTMC semantics. In: Theoretical Computer Science.

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(2021). Concurrency Theorems for Non-linear Rewriting Theories. In: ICGT 2021, Lecture Notes in Computer Science, vol 12741, 2021..

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(2021). Fusion of interfaces in Landau-Ginzburg models: a functorial approach. In: J. High Energ. Phys. 2021, 235 (2021)..

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(2021). Compositionality of Rewriting Rules with Conditions. Compositionality 3, 2 (2021)..

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(2021). On Stochastic Rewriting and Combinatorics via Rule-Algebraic Methods. Invited Paper in Patrick Bahr (ed.): Proceedings 11th International Workshop on Computing with Terms and Graphs (TERMGRAPH 2020), Online, 5th July 2020, Electronic Proceedings in Theoretical Computer Science 334, pp. 11–28..

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(2021). Stochastic Graph Transformation For Social Network Modeling. Proceedings Twelfth International Workshop on Graph Computational Models, Online, 22nd June 2021.

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(2020). Efficient Computation of Graph Overlaps for Rule Composition: Theory and Z3 Prototyping. In: B. Hoffmann and M. Minas: Proceedings of the Eleventh International Workshop on Graph Computation Models (GCM 2020), Online-Workshop, 24th June 2020, Electronic Proceedings in Theoretical Computer Science 330, pp. 126–144..

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(2020). Tracelets and Tracelet Analysis Of Compositional Rewriting Systems. In: John Baez and Bob Coecke: Proceedings Applied Category Theory 2019 (ACT 2019), University of Oxford, UK, 15-19 July 2019, Electronic Proceedings in Theoretical Computer Science 323, pp. 44-71..

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(2020). Combinatorial Conversion and Moment Bisimulation for Stochastic Rewriting Systems. In: Logical Methods in Computer Science, Volume 16, Issue 3.

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(2020). Rule Algebras for Adhesive Categories (invited extended jounral version). In: Logical Methods in Computer Science, Volume 16, Issue 3.

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(2020). Rewriting Theory for the Life Sciences: A Unifying Theory of CTMC Semantics. Graph Transformation, 13th International Conference, ICGT 2020, Proceedings, volume 12150 of Theoretical Computer Science and General Issues, Springer International Publishing.

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(2019). Sesqui-Pushout Rewriting: Concurrency, Associativity and Rule Algebra Framework. Electronic Proceedings in Theoretical Computer Science, 309:23–52.

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(2019). Dual Numbers and Operational Umbral Methods. In: Axioms, 8(3):77.

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(2019). Operator Ordering and Solution of Pseudo-Evolutionary Equations. In: Axioms, 8(1), p.35.

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(2019). Operational Methods in the Study of Sobolev-Jacobi Polynomials. In: Mathematics, (7), 2, pp. 124.

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(2018). Rule Algebras for Adhesive Categories. In: 27th EACSL Annual Conference on Computer Science Logic (CSL 2018), Schloss Dagstuhl–Leibniz-Zentrum fuer Informatik, Dagstuhl, Germany, pp. 11:1–11:21.

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(2017). Combinatorics of chemical reaction systems. In: arXiv preprint.

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(2016). The algebras of graph rewriting. In: arXiv preprint.

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(2016). Stochastic mechanics of graph rewriting. In: Proceedings of the 31st Annual ACM/IEEE Symposium on Logic in Computer Science - LICS ‘16, ACM Press.

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(2016). Holography as a highly efficient renormalization group flow. I. Rephrasing gravity. In: Physical Review D, (94), 2.

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(2015). Matrix factorisations for rational boundary conditions by defect fusion. In: Journal of High Energy Physics, (2015), 5.

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(2014). Renormalization and redundancy in 2d quantum field theories. In: Journal of High Energy Physics, (2014), 2.

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(2012). Variable transformation defects. Proceedings of Symposia in Pure Mathematics, Volume 85.

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(2011). New solid state lens for reflective neutron focusing. In: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, (634), 1, pp. S104–S107.

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(2010). D-branes and matrix factorisations in supersymmetric coset models. In: Journal of High Energy Physics, 11, (2010)136.

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(2008). Optical Antenna Properties of Scanning Probe Tips: Plasmonic Light Scattering, Tip-Sample Coupling, and Near-Field Enhancement. In: The Journal of Physical Chemistry C, (112), 10, pp. 3766–3773.

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(2007). Reply to ``Comment on `Scanning-probe Raman spectroscopy with single-molecule sensitivity' ''. In: Phys. Rev. B, (75), pp. 236402.

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(2006). Scanning-probe Raman spectroscopy with single-molecule sensitivity. In: Physical Review B, (73), 19.

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(2006). Ultrahigh resolution scattering near-field vibrational microscopy with single molecule sensitivity. In: 2006 Conference on Lasers and Electro-Optics and 2006 Quantum Electronics and Laser Science Conference, IEEE.

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Talks & Activities

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20/11 - 22/11/2024 Combinatorics and Arithmetic for Physics: special days workshop (invited talk), Institut des Hautes Études Scientifiques (IHÉS), Bures sur Yvette, France
10 - 11/07/2024 17th International Conference on Graph Transformation (ICGT 2024) (talk), Enschede, The Netherlands
24 - 25/06/2024 Journées PPS (talk), IRIF, Université Paris Cité, Paris, France
27 - 29/05/2024 Hypermatrix Workshop 2024 (talk), LPTMC, Sorbonne Université, Paris, France
21/05/2024 ANR CoREACT seminar (participant), online
16 - 17/05/2024 Quo Transformes? workshop (invited talk), University of Pisa, Italy
11 - 13/03/2024 ANR CoREACT General Meeting (participant), ENS Lyon, France
21 - 26/01/2024 Higher Segal Spaces and their Applications to Algebraic K-Theory, Hall Algebras, and Combinatorics workshop (invited participant), Banff International Research Station, Calgary, Canada
15/12/2023 MDENet France Workshop 2023 (participant), LIP6, Sorbonne Université, Paris, France
15/11 - 17/11/2023 Combinatorics and Arithmetic for Physics: special days workshop (participant), Institut des Hautes Études Scientifiques (IHÉS), Bures sur Yvette, France
19 - 20/07/2023 16th International Conference on Graph Transformation (ICGT 2023) (talk; video, slides), Leicester, UK
18/07/2023 14th International Workshop on Graph Computation Models (GCM 2023) (participant), Leicester, UK
26/06/2023 - 30/06/2023 Category Theory at Work in Computational Mathematics and Theoretical Informatics meeting (invited talk; slides), Lie-Størmer Center, Bergen, Norway
08/06/2023 - 09/06/2023 François Métayer days (participant), IRIF, Université Paris Cité, Paris, France
06/06/2023 - 07/06/2023 LHC days 2023, IRIF, Université Paris Cité, Paris, France
25/05/2023 - 26/05/2023 Journées PPS (talk; slides), IRIF, Université Paris Cité, Paris, France
24/04/2023 - 25/04/2023 IFIP WG1.3 Foundations of System Specification (participant), Paris, France
19/04/2023 ANR CoREACT kick-off meeting (participant/organiser), IRIF, Université de Paris, France
02/12/2022 Catégories supérieures, polygraphes et homotopie workgroup (talk), IRIF, Université de Paris, France
30/11/2022 - 02/12/2022 Virtual Double Categories Workshop (talk; slides, video), online
28/11 - 29/11/2022 Combinatorics and Arithmetic for Physics: special days workshop (invited talk; slides, video), Institut des Hautes Études Scientifiques (IHÉS), Bures sur Yvette, France
14 – 16/11/2022 GDR Renormalisation - Annual Meeting 2022: Hopf Algebras and Applications (talk), Univ. du Littoral Côte d’Opale Calais, France
14 – 16/09/2022 20th International Conference on Computational Methods in Systems Biology (CMSB 2022) (online participant), Bucharest, Romania
18 - 22/07/2022 APPLIED CATEGORY THEORY 2022 (online participant), University of Strathclyde, Glasgow, Scotland
07 - 08/07/2022 15th International Conference on Graph Transformation (ICGT 2022) (co-chair), Nantes, France
06/07/2022 13th International Workshop on Graph Computation Models (GCM 2022) (participant), Nantes, France
09/06/2022 Topos Institute Colloquium (talk), online
30/05 - 31/05/2022 Discrete-event systems and Environmental Sciences meeting (talk), Centre Inria de Paris, France
30/11 - 02/12/2021 Combinatorics and Arithmetic for Physics: special days workshop (invited talk; video, slides), Institut des Hautes Études Scientifiques (IHÉS), Bures sur Yvette, France
05/11/2021 GReTA international online seminar series (talk; video), online
12 - 16/07/2021 4th International Conference on Applied Category Theory (ACT 2021) (distinguished talk; video, slides, paper), online
24 - 25/06/2021 14th International Conference on Graph Transformation (ICGT 2021) (talk; paper, slides), online
22/06/2021 Twelfth International Workshop on Graph Computation Models (GCM 2021) (paper), online
11/06/2021 Algebraic and Combinatorial Perspectives in the Mathematical Sciences (ACPMS) seminar (talk), online
29/03/2021 LACL seminar (talk), Laboratoire d’Algorithmique, Complexité et Logique, Creteil, France
09/03/2021 Journée-séminaire de combinatoire, CALIN, Université Paris 13 (talk), online
10 - 11/12/2020 Species and operads in combinatorics and semantics workshop (talk; slides), IRIF, Université de Paris, France
02 – 03/12/2020 Combinatorics and Arithmetic for Physics: special days workshop (invited talk; video), Institut des Hautes Études Scientifiques (IHÉS), Bures sur Yvette, France
15/10/2020 Journées de rentrée PPS (talk), IRIF, Université de Paris, France
20/07/2020 CRI Research Collaboratory seminar (talk), Centre de Recherches Interdisciplinaires (CRI), Paris, France
5/07/2020 TERMGRAPH 2020: 11th International Workshop on Computing with Terms and Graphs (invited talk), online event
25 - 26/06/2020 ICGT 2020: 13th International Conference on Graph Transformation (talk), online event
24/06/2020 GCM 2020: Eleventh International Workshop on Graph Computation Models (talk), online event
14 - 15/05/2020 POSTPONED to spring 2021 due to COVID-19 pandemic Colloquium La biologie et la chimie de l’information (invited talk), Collège de France, Paris, France
05/03/2020 Computer Science Colloquium (talk), University of Southern Denmark, Odense, Denmark
21/02/2020 Informatics Seminar (talk), University of Leicester, UK
26/11/2019 LSV Seminar, Laboratoire Spécification et Vérification, ENS Paris-Saclay, Cachan, France
21/11/2019 Software Science Departmental seminar (talk), School of Information Technologies, TalTech, Tallinn, Estonia
06 - 08/11/2019 Combinatorics and Arithmetic for Physics: special days workshop (invited talk), Institut des Hautes Études Scientifiques (IHÉS), Bures sur Yvette, France
25/10/2019 FIAS CEF Symposium (talk), Frankfurt Institute for Advanced Studies, Germany
14/10/2019 seminar of the Research Group Theoretical Computer Science (talk), Universität Bremen, Germany
3/10/2019 PPS seminar (talk), IRIF, Université Paris Diderot, France
22 - 26/07/2019 15th International Symposium on Orthogonal Polynomials, Special Functions and Applications (OPSFA'15) (invited talk; slides, video), Research Institute for Symbolic Computation (RISC), Hagenberg, Austria
17/07/2019 Tenth International Workshop on Graph Computation Models (GCM 2019) (talk; slides), Eindhoven University of Technology, Eindhoven, The Netherlands
15 - 19/07/2019 Applied Category Theory Conference (ACT 2019), University of Oxford (talk; slides, video), Oxford, United Kingdom
28/05 - 02/ 06/2019 27th Foundational Methods in Computer Science Workshop (FMCS 2019; talk), University of Calgary, Alberta, Canada
06 - 07/ 05/2019 Tokenomics, International Conference on Blockchain Economics, Security and Protocols, ENS Paris, France
18 - 22/03/2019 Journées Aléa 2019, Centre International de Rencontres Mathématiques (CIRM), Marseille, France
19/02/2019 Calcul Natural (CANA) seminar (talk), Laboratoire d’Informatique Fondamentale de Marseille (LIF), Marseille, France
12 - 16/11/2018 Rencontres du GDR Renormalisation, Laboratoire de Mathématiques Blaise Pascal, Clermont-Ferrand, France
8 - 9/11/2018 Journées PPS (talk), IRIF, Université Paris Diderot, France
31/10/2018 Seminar of the Équipe Antique (talk), DI-ENS, Paris, France
24 - 25/10/2018 Combinatorics and Arithmetic for Physics: special days workshop (invited talk), Institut des Hautes Études Scientifiques (IHÉS), Bures sur Yvette, France
10 - 11/10/2018 Emergent Algorithms and Network Dynamics workshop (invited talk; slides), Institut Henri-Poincaré, Paris, France
01/10/2018 Séminaires du LPTMC, Sorbonne Université (Paris 6) (talk), France
09 - 12/09/2018 81st Séminaire Lotharingien de combinatoire (KrattenthalerFest), Strobl, Austria
04 - 07/09/2018 Computer Science Logic 2018 conference (talk), School of Computer Science of the University of Birmingham, UK
15 - 21/07/2018 18th Workshop: Noncommutative Probability, Operators Algebras, Random Matrices and Related Topics, with Applications (talk), Stefan Banach Conference Center of the Polish Academy of Sciences, Będlewo, Poland
29/05/2018 Journée-séminaire de combinatoire, Université Paris 13 (talk), France
13/02/2018 Séminaire Systèmes complexes, IRIF, Université Paris Diderot (talk), France
05/02/2018 Seminario di ENEA, Centro Ricerche Frascati, Rome (talk), Italy
11 - 12/01/2018 International Conference on Combinatorics and Physics (Penson71Fest) (invited talk), Polish Academy of Sciences Paris, France
09 - 10/11/2017 Combinatorics and Arithmetic for Physics: special days workshop (invited talk), Institut des Hautes Études Scientifiques (IHÉS), Bures sur Yvette, France
06/11/2017 IRIF Newcomers Day (talk), IRIF, Université Paris Diderot, France
18/10/2018 Équipe de travail Analyse et conception de systèmes (talk), IRIF, Université Paris Diderot, France
25/04/2017 Journée-séminaire de combinatoire (talk), Université Paris 13, France
09/02/2017 Séminaires d’Informatique Théorique (talk), DI Université de Rouen, France