I am a CNRS researcher working on early-universe cosmology at the Physics department of Ecole Normale Supérieure  (LPENS, Paris).

I did my PhD at the Institut d’Astrophysique de Paris between 2011 and 2014, and then worked as a postdoctoral researcher at the Institute of Cosmology and Gravitation at the University of Portsmouth in England. In 2017, I was hired by CNRS (the French National Centre for Scientific Research) on a permanent position, and joined the Laboratoire Astroparticules et Cosmologie in Paris. In 2022, I moved to ENS to create a new research group centred on theoretical cosmology and gravitation, together with Cedric Deffayet.

​My research focuses on understanding how cosmological structures arose from quantum fluctuations in the very early universe, and what cosmology can tell us about high-energy physics beyond the standard model, foundations of quantum mechanics and the nature of gravity.

Contact

L269
0766179607
LPENS
Laboratoire de physique
de l’Ecole normale supérieure
24 rue Lhomond 75005 PARIS

Publications

My list of publications can be accessed on Inspire by clicking this link (each entry contains a link to the openly accessible e-print version).

The list can also be checked on arXiv at this location​, and here is a link to my orcid profile.

Research

Over the past few decades, high-precision observations have revealed that the universe contains a variety of astrophysical objects ranging from asteroids and planets to stars, black holes, galaxies etc.

Those objects are arranged into large-scale structures, whose statistical properties have allowed cosmologists to constrain the main properties of the universe, the rate at which it expands and its fundamental constituents. 

​My work focuses on understanding how these structures emerged in the early universe, from the gravitational amplification of tiny quantum fluctuations. 

​By studying the detailed features of those primordial density fluctuations, my goal is to learn more about the physical conditions that prevailed in the early universe, and to test physics at energy scales that are much larger than what can be probed in particle-physics experiments.  

​More specifically, I am interested in

  • effective methods for the description of expanding backgrounds sourced by quantum fields (the so-called stochastic-inflation formalism)
  • the formation of primordial black holes from large primordial density fluctuations, and the associated gravitational-wave background
  • the quantum birth of cosmic structures (can we can prove their quantum-mechanical origin?)
  • foundational aspects of quantum mechanics in the cosmological context, and using cosmological measurements to test alternative formulations of quantum mechanics (for instance dynamical collapse models)
  • constraining models of the early universe and high-energy theories using measurements of the cosmic microwave background and of the large-scale structure

Teaching

I currently teach in the following programs:

  • I have a professor position in the Physics department of Ecole Polytechnique (Saclay, France). I teach special relativity and variational principles in the first semester, and quantum mechanics in the second semester
  • I teach in the theoretical-physics master program of Ecole Normale Supérieure (Paris, France). I give the cosmology course together with Jérôme Martin.
  • I teach in the yearly summer school of the Euclid collaboration, where I give a course on the physics of inflation.

Responsibilities

I commit to my scientific community by taking on various responsibilities, among which:

  • I am an elected member of the national committee of CNRS in section 02 (theoretical physics)
  • I am deputy director of the national research network (aka Groupement de Recherche, GdR) on Cosmology
  • I am a member of the steering committee of the Theory, Universe and Gravitation (TUG) network.