Theory of Fundamental Interactions (TIF)

The program of our mini-workshop Cosmology and High Energy Physics can be found HERE.

Our research activities span various domains, from formal subjects in quantum field theory and string theory, in connection with quantum gravity and cosmology, to particle phenomenology, linked to current experiments at the energy and intensity frontier, as well as in astroparticles. Our team also uses quantum field theory techniques to describe light-matter interactions in exotic materials, such as metamaterials, as well as for quantum machine learning applications.

We work in close collaboration with the team “Particles, Astroparticles, Cosmology: Theory” (PACT) of the Laboratoire Univers et Particules de Montpellier.

The TIF team is part of several research networks: the international research network Terascale; the national program PNHE; the European ITN project HIDDeN.

Several external collaborations are ongoing, e.g. with the Institute for the Physics of the Universe in Marseille (IPhU), with researchers from the ATLAS collaboration at CERN (Geneva), CPPM (Marseille) and IJCLab (Orsay), and with the Service de Physique Théorique at Université Libre de Bruxelles.

Research Fields :

• Quantum field theory : supersymmetric gauge theories; conformal field theories in two dimensions; non-perturbative aspects of field theories.
• Theory and phenomenology beyond Standard Model : grand unification theories (GUTs); flavour physics in the quark and lepton sectors; phenomenology at the large hadron collider (LHC) and other colliders; physics of neutrino masses and their detection; sterile neutrinos and baryogenesis via leptogenesis.
• Strongly-coupled theories beyond the Standard Model : models of Higgs compositeness; holography and gauge-gravity duality.
• Non-perturbative techniques in quantum field theories : variational methods, optimised perturbations, resummations, renormalisation group; applications in quantum chromo-dynamics (QCD), low-energy hadron physics, and condensed matter; studies of phase transitions at finite temperature and density.
• Phenomenology of supersymmetric models : minimal supersymmetric standard model (MSSM) and its extensions; supersymmetry breaking models (super-gravity, AMSB, GMSB); development of codes dedicated to the computation of super-particle spectra.
• Gravitational theories : canonical methods; modified gravity models; quantum gravity.
• Cosmology : dark energy models; inflationary models; study of the Universe expansion and growth of perturbations; physics of the very early Universe; generation of gravitational waves; big bang nucleosynthesis (BBN).
• Dark matter : theory and models; dark-matter candidates: neutralinos, gravitinos, singlinos, axions, sterile neutrinos, composite states; relic density calculations (WIMPs, FIMPs, etc.); theoretical analyses for direct and indirect dark-matter detection, as well as complementary searches at colliders.
• String theory : compactifications on Calabi-Yau threefolds and their orientifolds; flux compactifications; quantum corrections to effective actions; dualities; string phenomenology; swampland program; BPS black holes.
• Mathematical physics : integrability; BPS indices and topological invariants; modular and mock modular forms. Integral and asymptotic methods in classical and quantum scattering theory ; Homogenization techniques and singular perturbations ; Characteristic classes and algebraic topology in condensed matter.
• Light-matter interaction: Non-relativistic quantum field theory; QED; Semi-classical approaches; Maxwell-Bloch equations; metamaterials; electromagnetism.
• Quantum machine learning: Quantum reservoir computing

Funding : QRC-4-ESP

TIF team participates in the QRC-4-ESP project (https://www.qrc-4-esp.eu), funded by the European Innovation Council, which aims to implement reservoir computing principles using physical systems.

More specifically, the TIF team is working to develop a general theory of prediction using reservoirs governed by the laws of classical or quantum physics. We are also focused on optimizing predictions made using reservoirs composed of either superconducting qubits or luminescent point-defects in silicon carbide.