Discord and nonclassicality in probabilistic theories.
نویسنده
چکیده
Quantum discord quantifies nonclassical correlations in quantum states. We introduce discord for states in causal probabilistic theories, inspired by the original definition proposed by H. Ollivier and W. H. Zurek [Phys. Rev. Lett. 88, 017901 (2001)]. 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 nonclassicality.
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ورودعنوان ژورنال:
- Physical review letters
دوره 108 12 شماره
صفحات -
تاریخ انتشار 2012