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arXiv · 1408.2272

Multiple Observers Can Share the Nonlocality of Half of an Entangled Pair by Using Optimal Weak Measurements

Ralph Silva·Nicolas Gisin·Yelena Guryanova·Sandu Popescu
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Abstract

We investigate the trade-off between information gain and disturbance for a class of weak von Neumann measurements on spin-$\frac{1}{2}$ particles, and derive the unusual measurement pointer state that saturates this trade-off. We then consider the fundamental question of sharing the non-locality of a single particle of an entangled pair among multiple observers, and demonstrate that by exploiting the information gain disturbance trade-off, one can obtain an arbitrarily long sequence of consecutive and independent violations of the CHSH-Bell inequality.

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Ralph Silva, Nicolas Gisin, Yelena Guryanova, Sandu Popescu. 2014-08-10. Multiple Observers Can Share the Nonlocality of Half of an Entangled Pair by Using Optimal Weak Measurements. https://doi.org/10.1103/physrevlett.114.250401

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