Gravitational Waves from the Fifth Dimension

The experimental revolution unleashed by the discovery of gravitational waves will gradually unfold over the coming decades. Maximizing the discovery potential requires a theoretical understanding of out-out-of-equilibrium quantum matter coupled to dynamical classical gravity. I will discuss the insights that holography can offer into this challenging regime. I will focus on phase transitions in the early Universe and in neutron star mergers. If time permits I will also discuss the holographic dual of primordial black hole formation as well as the approach to a cosmological singularity.