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arXiv · hep-th/9306087

Causality Constraints on Nonlocal Quantum Measurements

Sandu Popescu·Lev Vaidman
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Abstract

Consequences of relativistic causality for measurements of nonlocal characteristics of composite quantum systems are investigated. It is proved that verification measurements of entangled states necessarily erase local information. A complete analysis of measurability of nondegenerate spin operators of a system of two spin-1/2 particles is presented. It is shown that measurability of certain projection operators which play an important role in axiomatic quantum theory contradicts the causality principle.

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Sandu Popescu, Lev Vaidman. 1993-06-18. Causality Constraints on Nonlocal Quantum Measurements. https://doi.org/10.1103/physreva.49.4331

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