New symmetries in general relativity

by Simone Speziale (Aiix-Marseille Université, Francia)

Thursday 10 Feb 2022, 16:00 → 17:30 Europe/Rome

Aula Conversi (Dip. di Fisica - Edificio G. Marconi)

Seminario di Fisica della gravitazione.

In the last few years there has been a lot of interest in asymptotic symmetries in gauge theories and general relativity, in relation with deep infrared problems and memory effects. I will first give a brief pedagogical introduction showing how the surface charges associated with asymptotic symmetries follow from a standard application of Noether's theorem, and then discuss some extensions of the BMS symmetries that have been proposed in the context of general relativity, with their motivations. Among the results, a derivation of the flux-balance laws of gravitational waves from Noether's theorem, new memory effects associated with the extensions, and the possibility of discriminating bulk-equivalent descriptions of gravity such as metric and tetrad formulations. I will conclude with a brief outlook on the possibility of detecting the new memory effects, and speculative implications for quantum gravity.