The Theory group currently has fourteen permanent members, including four CNRS researchers, seven professors from Université de Nantes and three professors from IMT Atlantique.
The research themes of the group are centered on nuclear physics, hadronic physics and particle physics in relation with experiments carried out at major accelerators such as the LHC at CERN, with applications in the physics of cosmic rays, of astroparticles and in cosmology. The group is also developing research themes going towards chemistry and molecular physics, as well as mathematical physics with the study of supersymmetry in Quantum Field Theory.
More in detail, the main research axes of the group are
- the quark-gluon plasma, which is produced in the first instants of high-energy heavy-ion collisions. We are interested on the effect of the plasma on hard probes (quarkonia, heavy flavours and jets), on thermodynamical aspects through the PNJL model, as well as on the development of Thermal Field Theory and on the search for the critical point of the phase diagram of Quantum ChromoDynamics through the investigation of fluctuations. The group also has a long-standing expertise in the development of codes simulating heavy-ion collisions (EPOS, MC@HQ models).
- cold nuclear matter which is probed by proton-nucleus collisions. The effects of induced radiation and energy loss are studied in the framework of perturbative Quantum ChromoDynamics, together with the effects of parton distributions within nuclei.
- the physics of gluon saturation in very high-energy lepton-nucleus or proton-nucleus collisions probed at the LHC and the future Electron-Ion Collider. In this regime, the density of gluons in atomic nuclei is large and this growth is tamed by the non-linearity of gluon self-interactions. We study this emergent state of matter with saturated gluons, which is predicted by quantum chromodynamics, and we calculate observables that are relevant to its experimental demonstration.
- nuclear physics, with the developement of a transport model to study the dynamics of heavy-ion collisions at Fermi energies and the theoretical study of the stopping power of nuclear matter. The dynamical processes of fusion and evaporation of the nuclear medium are investigated with the help of classical molecular dynamics. At slightly higher energies (GSI-FAIR/NICA), the equation of state of nuclear matter is studies through azimuthal asymmetries measured in heavy-ion collisions.
- supersymmetry and field theory, with the study of supersymmetric Yang-Mills theories. The methods of supersymmetric quantum mechanics are also investigated, namely with the outlook of solving non-trivial problems in differential geometry and mathematics.
- cosmology, in particular the study of the Standard Model of particle physics and its extensions within the hot medium of the early universe before big-bang nucleosyntesis, with the aim of addressing important open questions such as the nature of dark matter or the origin of the baryon asymmetry of the universe.
- Nuclear reactions at low and intermediate energy with the help of a generalized liquid drop model: fusion, fission, cluster emission, alpha emission, 2p emission, formation and decay of superheavy nuclei, molecular nuclei, fragmentation.
The group has strong links with the experimental activies at SUBATECH, for instance the plasma group, be it to decipher new results or to guide future searches. Many of the themes studied by the research group need numerical solutions, developed exploiting the group's skills in modeling and simulation.