Neutron star physics, neutron star mergers, near-extremal black holes and effective theories near absolute zero.

This project involves using techniques from the AdS/CFT correspondence (known also as holography) to understand

(a) The non-trivial phases in the QCD phase diagram, involving non zero baryon number density as well as non-zero isospin density.

(b) The statics and dynamics in non-trivial phases relevant for neutron stars, where very low temperatures are relevant.

Dynamique des systèmes binaires en relativité générale et perturbations des trous noirs en gravité modifiée

Aspects of Holographic Quantum Field Theories on Curved Spacetimes

The thesis will focus on the study of the properties of holographic quantum field theories on curved background, with the applications to cosmology and to quantum field theories with defects.

Neutrinos: from the discovery of the diffuse supernova background to entanglement

Neutrinos are elementary massive particles with mixings. They change their flavor while propagating. The vacuum oscillations discovered in 1998 by the Super-Kamiokande Collaboration is a breakthrough, with an impact in particle physics, astrophysics and cosmology.

Non-linear aspects and symmetries of black hole perturbation theory

The thesis will study theoretical aspects and symmetries of black hole perturbation theory, with applications to future gravitational-wave observations.

MULTI-MESSENGER ASTRONOMY AT THE HIGHEST ENERGY FRONTIER

The discovery of astrophysical neutrino signal by IceCube neutrino telescope has extended the energy frontier of astronomy into Peta-electronvolt energy range. The nature of astronomical sources is currently uncertain. A breakthrough toward understanding of the nature of these sources can be achieved via detection of the gamma-ray counterpart of the astrophysical neutrino signal. Gamma-ray signal at 100 TeV is now detectable by the HAWC, Tibet and LHAASO telescopes. Further powerful observational facilities, like CTA and SWGO telescopes are under construction or planned.

NUMERICAL MODEL OF THE MULTI-MESSENGER SIGNAL FROM THE MILKY WAY GALAXY AT PEV ENERGY

Astronomical observations through the new 100 TeV gamma-ray observational window by HAWC, Tibet and LHAASO air shower arrays, and, in the near future, by the Cherenkov Telescope Array CTA open a range of completely new possibilities for the study of highest energy galactic cosmic ray sources. These sources, dubbed "PeVatrons" (yet to be identified) produce particles with energies in excess of Peta-electronVolt, three orders of magnitude higher than those attained in the most powerful human-made accelerator LHC.

“Neutrinos : from the discovery of the diffuse supernova neutrino background to new physics”

Neutrinos are elementary massive particles with mixings. They change their flavor while propagating. The vacuum oscillations discovered in 1998 by the Super-Kamiokande Collaboration is a breakthrough, with an impact in particle physics, astrophysics and cosmology.

Strong coupling physics, holography and cosmology

RESEARCH THEME: Using the AdS/CFT correspondence to study de Sitter space and Inflation driven at strong coupling.

Extreme phases of matter

RESEARCH THEME: Using the AdS/CFT correspondence to study phases of gauge theories, at strong coupling at finite temperature and density. A related problem is to understand the physics of cold nuclear matter at the center of neutron stars..

LABORATOIRE

ASTROPARTICULE & COSMOLOGIE

Théorie