Robinson-Trautman spacetimes and gauge/gravity duality

Understand

We study far-from-equilibrium field theory dynamics using gauge/gravity duality applied to the Robinson-Trautman (RT) class of spacetimes and we present a number of new results.

• First, we assess the applicability of the hydrodynamic approximation to inhomogeneous plasma dynamics dual to RT spacetimes.
• We prove that to any order in a late time expansion it is possible to identify variables corresponding to the local energy density and fluid velocity.
• However, we show using numerical examples that this does not hold at the non-perturbative level; for sufficiently inhomogeneous initial data a local rest frame does not exist.