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arXiv · 0906.2000

Local and global statistical distances are equivalent on pure states

Scott M. Cohen
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Abstract

The statistical distance between pure quantum states is obtained by finding a measurement that is optimal in a sense defined by Wootters. As such, one may expect that the statistical distance will turn out to be different if the set of possible measurements is restricted in some way. It nonetheless turns out that if the restriction is to local operations and classical communication (LOCC) on any multipartite system, then the statistical distance is the same as it is without restriction, being equal to the angle between the states in Hilbert space.

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Scott M. Cohen. 2009-06-10. Local and global statistical distances are equivalent on pure states. https://doi.org/10.1103/physreva.80.032323

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