Dynamics of an Acoustic Black Hole as an Open Quantum System
  We studied the process of decoherence induced by the presence of an environment in acoustic black holes, using the open quantum system approach, thus extending previous work. We focused on the ion trap model but the formalism is general to any experimental implementation. We computed the decoherence time for that setup. We found that a quantum to classical transition occurs during the measurement and we proposed improved parameters to avoid such a feature. We provide analytic estimations for both zero and finite temperature. We also studied the entanglement between the Hawking-pair phonons for an acoustic black hole while in contact with a reservoir, through the quantum correlations, showing that they remain strongly correlated for small enough times and temperatures. We used the stochastic formalism and the method of characteristic to solve the field wave equation. 
Fernando C. Lombardo and Gustavo J. Turiaci
quant-ph gr-qc hep-th