APEC Seminar (Astronomy - Particle Physics - Experimental Physics - Cosmology)

Speaker: Antonio Padilla (Nottingham U)
Title: Dark energy some time after GW170817
Date (JST): Wed, Jul 22, 2020, 17:00 - 18:00
Place: Zoom
Related File: 2556.pdf
Abstract: We revisit the constraints on scalar tensor theories of modified gravity following the purge of GW170817. We pay particular attention to dynamical loopholes where the anomalous speed of propagation of the gravitational wave can vanish on-shell, when we impose the dynamical field equations. By working in the effective field theory formalism we are able to improve on previous analyses, scanning a much wider class of theories, including Beyond Horndeski and DHOST.
Furthermore, the formalism is well adapted to consider the effect of inhomogeneous perturbations, where we explicitly take into account the fact that the galactic over densities are pressureless to leading order.