Physical transformations between quantum states
نویسندگان
چکیده
Given two sets of quantum states {A1, . . . , Ak} and {B1, . . . , Bk}, represented as sets as density matrices, necessary and sufficient conditions are obtained for the existence of a physical transformation T , represented as a trace-preserving completely positive map, such that T (Ai) = Bi for i = 1, . . . , k. General completely positive maps without the trace-preserving requirement, and unital completely positive maps transforming the states are also considered.
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