Speaker: Valerio De Luca, University of Pennsylvania
Title: Gravitational memory and soft theorems: the local perspective
Abstract: Gravitational memory describes the permanent imprint on freely falling detectors after a passing gravitational wave, and it has been intimately connected to Bondi-Metzner-Sachs symmetries at future null infinity and soft theorems. In this talk, we will explore the relation between gravitational memory and Bondi-Metzner-Sachs symmetries in synchronous coordinates - relevant for gravitational wave detectors like LISA - and show that it corresponds to large residual diffeomorphisms, such as volume-preserving spatial rescalings. We will also present soft theorems for both scattering amplitudes and equal-time in-in correlation functions. The latter are recognized as the flat-space analog of inflationary consistency relations.