My talk will focus on the structure of gravity at large distances and especially on how one can get insights on the asymptotically flat structure from the one of Anti-de Sitter spacetimes. I will start by recalling some basics on the gauge fixing approach to the IR structure of gravity, insisting on the fundamental examples of the Fefferman-Graham and Bondi gauges and on asymptotically AdS and flat spacetimes. As Ricci flat solutions are usually obtained from a the \Lambda -> 0 limit of Einstein´s spacetimes, I will describe how one can get the flat solution space and flux/balance equations from a careful Laurent expansion of the AdS energy-momentum tensor and the requirement of the line-element finiteness, the analysis being conducted in a covariant version of the Newman-Unti gauge that will be presented prior to these developments.
Matthieu Vilatte (Paris, Thessaloniki): Probing the asymptotic structure of 4d Einstein gravity: flat from AdS
