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arXiv · 1201.4421

Quantum discord and noncontextual hidden variables models

Kazuo Fujikawa
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Abstract

It is shown that theoretically viable noncontextual hidden variables models in $d=2$ lead to conflicting dispersion free expressions in the analysis of the conditional measurement of two non-orthogonal projectors. No satisfactory criterion of the quantum discord, which relies on the analysis of conditional measurement, is formulated in the $d=2$ hidden variables space due to a lack of uniqueness of the dispersion free representation. We also make a speculative comment on a "many-worlds interpretation" of hidden variables models to account for the conditional measurement.

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Kazuo Fujikawa. 2012-01-21. Quantum discord and noncontextual hidden variables models. https://doi.org/10.1103/physreva.85.012114

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