Asymptotic flatness at timelike infinity

Abstract

BMS symmetries have been argued to be the exact symmetries of quantum gravity theory in asymptotically flat spacetimes. If this is the case, then they should also be visible at timelike infinity as well. In this thesis, we introduce a notion of asymptotically flat spacetimes at timelike infinity and discuss boundary conditions that allow for BMS symmetries to act on the space of solutions. The BMS symmetries lead to non-trivial conserved charges and conservation laws.