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arXiv · 2008.03302

The operational reality of quantum nonlocality

R. Srikanth
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Abstract

Does the remote measurement-disturbance of the quantum state of a system $B$ by measurement on system $A$ entangled with $B$, constitute a real disturbance -- i.e., an objective alteration -- of $B$ in an operational sense? Employing information theoretic criteria motivated by operational considerations alone, we argue that the disturbance in question is real for a subset of steerable correlations. This result highlights the distinction between quantum no-signaling and relativistic signal-locality. It furthermore suggests a natural reason why a convex operational theory should be non-signaling: namely, to ensure the consistency between the properties of reduced systems and those of single systems.

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R. Srikanth. 2020-08-10. The operational reality of quantum nonlocality. https://doi.org/10.1103/physreva.106.012221

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