My talk will start with a short introduction highlighting the relevance of Gravitational Waves (GWs), both resolvable and Stochastic GW Backgrounds (SGWBs), for cosmology. I will proceed by flashing detection techniques and prospects with future interferometers. The bulk of my seminar focuses on describing some of my recent works (e. g., 2203.00566, 2112.06903) that show the ability of GWs to constrain fundamental/high-energy physics. The last part of my seminar will be devoted to conclusions and future perspectives for the research field.

zoom link: https://univ-amu-fr.zoom.us/j/91448970216?pwd=SzhmcmRmVmpIY2l0a0JRSUpNdyszdz09

Gravitational waves (GWs) are novel signals that probe the behavior of gravity in both the strong and weak-field regimes. As these waves propagate towards us over cosmological distance, they are sensitive to the expansion rate of the Universe, the gravitational self-interactions, and the presence of cosmological fields. In this talk, I will first illustrate how we can constrain the properties of gravity and dark energy with GWs. After that, I will show that, similarly to light, GWs can be gravitationally lensed by intervening galaxies or clusters of galaxies. One important difference with light though is that the detection of GWs is sensitive to the phase of the wave, which can change due to gravitational lensing. I will discuss what this change of phase is, how it can affect observations, and how it can be used as a unique signature to help identify future GW lensed events, which will in turn open the way for even further cosmological science with GWs.

zoom link: https://univ-amu-fr.zoom.us/j/91448970216?pwd=SzhmcmRmVmpIY2l0a0JRSUpNdyszdz09

Gravitational waves promise to give answers to a number of fundamental
questions like the nature of gravity in the regime of strong
gravitational fields, the Kerr hypothesis, the dark matter and dark
energy puzzle, etc. The next generation of gravitational wave
detectors will observe hundreds of thousands of events per year
starting the era of high-precision gravitational wave astrophysics. In
the present talk, I will discuss what are our present and future
capabilities to test fundamental physics through gravitational waves.
I will focus primarily on merging compact binaries, as well as extreme
mass ratio inspirals and binary pulsars. Especially interesting are
the combinations of theories and astrophysical scenarios that give not
only small cumulative deviations with respect to general relativity
but also clear qualitatively different gravitational wave signatures
that are smoking guns for beyond-GR physics. Despite the rapid
development of the field, the theoretical modeling of such dynamical
processes beyond pure general relativity is still very limited leaving
space for exciting new discoveries.