Organizing commitee: Brando Bellazzini, John Joseph Carrasco and Filippo Vernizzi Effective field theory is one of the deepest and most useful guiding principles in physics. Its tools and methods allow one to study the universal aspects of entire classes of unknown microscopic models, with their main features being captured by symmetries and few relevant parameters of the effective degrees of freedom. Because of its universality, it finds applications across all scale in physics: from superHubble scales all the way to the Planck length. It is successfully applied to cosmology to describe the early cosmic inflation, the current cosmic acceleration, the dynamics of the large scale structure and the dark matter. Its methods have found recent applications in the theory of gravitational wave emission by binary inspirals, and in the new multimessanger astrophysics: new and conceptually compelling ways to perform calculations and predictions are being developed by making contact with the methods of scattering amplitudes of particle physicists. ... 

F. David, 20190221

This past year a team at IPhT around John Joseph Carrasco — in collaboration with physicists at UCLA and Penn State University in the United States, and Uppsala University in Sweden — completed a calculation long thought to be impossible: the direct understanding of the dimensions of spacetime in which the most symmetric particlebased field theory of gravity (maximal supergravity) would cease to be predictive when quantum effects are relevant. One can isolate order by order the quantum effects in graviton scattering. For two gravitons scattering off of each other, this calculation required consideration of the fifthorder quantum correction. This puts strong constraints on the behavior of fundamental symmetries in controlling the highenergy behavior of this theory. 

C. Pepin, 20181218

Periodically driven quantum manybody systems (such as cold atoms in timedependent optical lattices and quantum materials under ultrafast optical excitation) offer exciting perspectives of exploring quantum phases of matter along genuine nonequilibrium pathways.This socalled Floquet engineering relies, however, on the suppression of heating, i.e. the uncontrolled energy absorption from the drive. This was known to be the case only in the limit of extremely high frequency,thus limiting its practical use. A team at IPhT around Francesco Peronaci, Marco Schiro and Olivier Parcollet showed that also strong electronic interactions can largely circumvent energy absorption, and thus provide a robust 

C. Pepin, 20181213
