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arXiv · 1112.5066

Discord and non-classicality in probabilistic theories

Paolo Perinotti
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Abstract

Quantum discord quantifies non-classical correlations in quantum states. We introduce discord for states in causal probabilistic theories, inspired by the original definition proposed in Ref. [17]. We show that the only probabilistic theory in which all states have null discord is classical probability theory. Non-null discord is then not just a quantum feature, but a generic signature of non-classicality.

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Paolo Perinotti. 2011-12-21. Discord and non-classicality in probabilistic theories. https://doi.org/10.1103/physrevlett.108.120502

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