Speaker: Michele Maggiore (University of Geneva)
Title: Testing dark energy with gravitational waves
Abstract: Future GW detectors such as LISA and the Einstein telescope T will be able to measure binary neutron star coalescences up to cosmological distances. This will allow us to explore the dark-energy sector of generic modifications of General Relativity. In the dark energy sector a well-know observable is the equation of state of dark energy. However, its determination with LISA and ET will probably not be significantly better than what can already be obtained with electromagnetic observations (CMB, BAO, Supernovae). We will discuss recent work that shows that there is another way of testing the dark-energy sector, through modified GW propagation. This observable is more promising than the dark energy equation of state, and specific to GW observations.