From shockwaves to gravitational memory: new approaches in flat space holography

by Zurek Kathrin & Papucci Michele (Caltech University)

Tuesday 12 Dec 2023, 16:00 → 18:00 Europe/Rome

Aula Conversi (Dipartimento di Fisica - Ed. G. Marconi)

We consider metric fluctuations from shockwaves produced by vacuum energy fluctuations, and discuss possible observational implications.  We first show how the ’t Hooft commutation relations of shockwave operators are equivalent to the commutation relation between soft and Goldstone modes familiar from celestial holography. We demonstrate this equivalence via a diffeomorphism that takes the shockwave metric to a memory metric.  Next we show that the shockwave effective action is equivalent to an object very similar to the modular Hamiltonian. We compute the fluctuations in the modular Hamiltonian implied by the ’t Hooft commutation relations, and show they obey an area law.