Repeated Quantum Interactions and Unitary Random Walks
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چکیده
Among the discrete evolution equations describing a quantum system HS undergoing repeated quantum interactions with a chain of exterior systems, we study and characterize those which are directed by classical random variables in RN . The characterization we obtain is entirely algebraical in terms of the unitary operator driving the elementary interaction. We show that the solutions of these equations are then random walks on the group U(H0) of unitary operators on H0.
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تاریخ انتشار 2010