Unruh radiation, holography, and boundary cosmology - art. no. 104001

A uniformly accelerated observer in anti-de Sitter spacetime is known to de tect thermal radiation when the acceleration exceeds a critical value. We i nvestigate the holographic interpretation of this phenomenon. For uniformly accelerated trajectories transverse to the boundary of the AdS space, the hologram is a blob that expands along the boundary. Observers on the bounda ry comoving with the hologram become observers, in cosmological spacetimes. For supercritical accelerations one gets a Milne universe when the hologra phic screen is the boundary in Poincare coordinates, while for the boundary in hyperspherical coordinates one gets de Sitter spacetimes. The presence or absence of thermality is then interpreted in terms of specific classes o f observers in these cosmologies.