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Bell's theorem for general N-qubit states

Marek Zukowski·Caslav Brukner
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Abstract

We derive a single general Bell inequality which is a necessary and sufficient condition for the correlation function for N particles to be describable in a local and realistic picture, for the case in which measurements on each particle can be chosen between two arbitrary dichotomic observables. We also derive a necessary and sufficient condition for an arbitrary N-qubit mixed state to violate this inequality. This condition is a generalization and reformulation of the Horodeccy family condition for two qubits.

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Marek Zukowski, Caslav Brukner. 2002-09-16. Bell's theorem for general N-qubit states. https://doi.org/10.1103/physrevlett.88.210401

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