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arXiv · 1909.11785

Device-Independent Secret Sharing and a Stronger Form of Bell Nonlocality

M. G. M. Moreno·Samuraí Brito·Ranieri V. Nery·Rafael Chaves
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Abstract

Bell nonlocality, the fact that local hidden variable models cannot reproduce the correlations obtained by measurements on entangled states, is a cornerstone in our modern understanding of quantum theory. Apart from its fundamental implications, nonlocality is also at the core of device-independent quantum information processing, which successful implementation is achieved without precise knowledge of the physical apparatus. Here we show that a stronger form of Bell nonlocality, for which even nonlocal hidden variable models cannot reproduce the quantum predictions, allows for the device-independent implementation of secret sharing, a paradigmatic communication protocol where a secret split amidst many possibly untrusted parts can only be decoded if they collaborate among themselves.

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M. G. M. Moreno, Samuraí Brito, Ranieri V. Nery, Rafael Chaves. 2019-09-25. Device-Independent Secret Sharing and a Stronger Form of Bell Nonlocality. https://doi.org/10.1103/physreva.101.052339

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