Unruh effect as a noisy quantum channel

We studied the change of the nonlocal correlation of the entanglement in Rindler space-time by showing that the Unruh effect can be interpreted as a noisy quantum channel having a complete positive and trace preserving map with an "operator sum representation." It is shown that the entanglement fidelity is obtained in analytic form from the operator sum representation, which agrees well numerically with the entanglement monotone and the entanglement measure obtained previously. Nonzero entropy exchange between the system Q and region II of the Rindler wedge indicates the nonlocal correlation between causally disconnected regions. We have also shown the subadditivity of entropies numerically.