Spread of entanglement for small subsystems in holographic CFTs

Understand

We develop an analytic perturbative expansion to study the propagation of entanglement entropy for small subsystems after a global quench, in the context of the AdS/CFT correspondence.

• Opposite to the large interval limit, in this case the evolution of the system takes place at timescales that are shorter in comparison to the local equilibration scale and thus, different physical mechanisms govern the dynamics and subsequent thermalization.
• In particular, we show that the heuristic picture in terms of a "entanglement tsunami" does not apply in this regime.
• We find two crucial differences.