A ug 2 00 6 The Convex Closure of the Output Entropy of Infinite Dimensional Channels and the Additivity Problem
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On approximation of infinite-dimensional quantum channels
Abstract—We develop an approximation approach to infinite-dimensional quantum channels based on a detailed investigation of continuity properties of entropic characteristics of quantum channels and operations (trace-nonincreasing completely positive maps) as functions of a pair “channel, input state.” Obtained results are then applied to the problems of continuity of the χ-capacity as a functio...
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تاریخ انتشار 2006