Speaker
Description
This talk is motivated by the broad aim of a developing a fully nonlinear understanding of the nature of gravitational waves in asymptotically locally de Sitter (dS) spacetimes. I will begin with a review of the asymptotics of dS spacetimes, before showing (via the covariant phase space formalism) that spacetimes admitting suitable symmetries have spatially invariant charges. Relaxing the global requirement of such symmetries, I will present flux formulae which capture the effects of outgoing gravitational radiation and illustrate these via application to exact solutions, with particular emphasis on the Robinson-Trautman dS class. This talk is based on Phys.Rev.D 106 (2022) 6, L061901 and upcoming work in collaboration with Kostas Skenderis and Marika Taylor.
