Quantum electrodynamics for relativistic quantum chemistry

As part of the collaborative mathematics/chemistry project MaQuI, we are hiring a PhD student (3
years) to work on questions related to quantum electrodynamics (QED) applied to quantum chemistry.
QED is, in principle, the most fundamental and precise physical theory to incorporate relativistic
effects in quantum chemistry. However, practical methods for performing systematic calculations
based on this theory for realistic molecular systems do not yet exist.
The project aims to develop new electronic structure methods, in particular within the framework
of density functional theory (DFT), based on a variational formulation of QED.
The work may involve several complementary aspects:
• Theoretical and formal developments to derive new electronic structure methods from QED;
• More applied methodological developments, including the treatment of renormalization in a finite
basis;
• Software implementation and development, integrating the newly developed methods into quan-
tum chemistry codes.

Working Environment: The PhD student will be hosted at the Laboratory of Theoretical Chemistry, Sorbonne University and CNRS (4 place Jussieu, 75005 Paris). The PhD student will work primarily with Julien Toulouse (Sorbonne University and CNRS) and in collaboration with mathematicians Mathieu Lewin (CNRS and Université Paris Dauphine–PSL) and Éric Cancès (École Nationale des Ponts et Chaussées, CNRS and Institut Polytechnique de Paris).

Starting Date: From 01/10/2026

Le Laboratoire de Chimie Théorique (LCT), Sorbonne Université et CNRS, conduit des recherches dans tous les domaines de la physicochimie théorique, allant du développement de nouvelles théories physiques et mathématiques pour simuler la matière jusqu'aux applications en chimie, matière condensée et spectroscopie.  

Master degree in theoretical chemistry or physics (or a related field such as applied mathematics), with strong skills in quantum mechanics and a keen interest in interdisciplinary interactions with mathematicians.