The causal boundary of product spacetimes

Abstract

The new formulation of the causal completion of spacetimes suggested in Marolf and Ross (Class Quant Grav 20:4085, 2003), and modified later in Flores (Commun Math Phys 2007), is tested by computing the causal boundary for product spacetimes of a Lorentz interval and a Riemannian manifold. This is particularized for two important families of spacetimes, conformal to the previous ones: (standard) static spacetimes and Generalized Robertson-Walker spacetimes. As consequence, it is shown that this new approach essentially reproduces the structure of the conformal boundary for multiple classical spacetimes: Reissner–Nordstrom (including Schwarzschild), Anti-de Sitter, Taub and standard cosmological models as de Sitter and Einstein Universe.