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arXiv · 1704.02000

Classical-hidden-variable description for entanglement dynamics of two-qubit pure states

L. S. Silveira·R. M. Angelo
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Abstract

A hidden-variable model is explicitly constructed by use of a Liouvillian description for the dynamics of two coupled spin-1/2 particles. In this model, the underlying Hamiltonian trajectories play the role of deterministic hidden variables, whereas the shape of the initial probability distribution figures as a hidden variable that regulates the capacity of the model in producing correlations. We show that even though the model can very well describe the short-time entanglement dynamics of initially separated pure states, it is incapable of violating the Clauser-Horne-Shimony-Holt inequality. Our work suggests that, if one takes the reluctance of a given quantum resource to be emulated by a local-hidden-variable model as a signature of its nonclassicality degree, then one can conclude that entanglement and nonlocality are nonequivalent even in the context of two-qubit pure states.

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L. S. Silveira, R. M. Angelo. 2017-06-05. Classical-hidden-variable description for entanglement dynamics of two-qubit pure states. https://doi.org/10.1103/physreva.95.062105

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