  We studied the change of the nonlocal correlation of the entanglement in
Rindler spacetime 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. Non-zero entropy exchange between the system Q and the
region II of the Rindler wedge indicates the nonlocal correlation between
casually disconnected regions. We have also shown the sub additivity of
entropies numerically.
