Louis Lemonnier

  • I have been a PhD student since September 2021 under the supervision of Benoît Valiron and Vladimir Zamdzhiev.
  • Member of QuaCS (an Inria Saclay team) of the LMF laboratory.
  • You can find my CV here. I'll try to update it as regularly as possible.


I will defend my thesis on 19th June 2024, at 2pm. You can find more details here and please contact me if you have any questions.


For research or teaching purposes, don't hesitate to get in touch with me at: lemonnier (at) lmf (dot) cnrs (dot) fr.


My research interests have been significantly influenced by the topics of some courses given at the late ENS Cachan; thus, I'm curious about anything that gravitates toward type theory, (denotational) semantics of programming languages, logic and rewriting systems. I was also willing to keep studying physics when I started in ENS, which led me to work on quantum information and quantum computing.

The topic of my PhD was categorical denotational semantics of quantum-controlled recursion at the start. Moreover, on a more practical aspect, I am meant to spend some time imagining and compiling a programming language aimed at quantum optics.

I happen to be very interested in the study of computational effects through category theory, especially non-classical ones: differential, probabilistic, or quantum.

More generally, there are several topics that I have worked on, would like to work on or that I enjoy reading about:

  • any model or mathematical structure used in quantum computation, with a special spark for category theory, and I could not live without this,
  • quantum physics,
  • graphical calculi, especially ZX and ZH-calculus,
  • type theory (I want to finish reading HoTT at some point),
  • semantics of programming languages,
  • topology.





  • Project: Go compiler in OCaml.
  • Programming and semantics, exercise sessions. My ressources (in French).
  • Another project: webpage.

Preprints, Publications and corresponding Talks

Co-authored with Kostia Chardonnet and Benoît Valiron. Semantics for a Turing-complete Reversible Programming Language with Inductive Types. FSCD'24. arXiv link.

Co-authored with Titouan Carette and Vladimir Zamdzhiev. Central Submonads and Notions of Computation. LICS'23. arXiv link. Slides.

Co-authored with Titouan Carette. Large-scale quantum diagrammatic reasoning tools, !-boxes vs. scalable notations. Preprint. arXiv link.

Co-authored with Kostia Chardonnet and Benoît Valiron. Categorical Semantics of Reversible Pattern-Matching. MFPS'21. arXiv link. Slides.

Co-authored with John van de Wetering and Aleks Kissinger. Hypergraph Simplification: Linking the Path-sum Approach to the ZH-calculus. QPL'20. arXiv link. Slides.

Non published Talks

Semantics of Recursion in Quantum Control. French GT IQ 2023 (National quantum information working group). Slides.

Other interests

To contact me about anything in this section: llemonnier (at) crans (dot) org.

Outside mathematics and computer science, I spend a lot of time learning about natural and constructed languages. I have never focused my full attention on one in particular. Thus, I have medium knowledge in many languages, and I speak a few of them. My goal is to eventually create a language I am proud of, which will take a while.

I also play the bass when I find the time.