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arXiv · 1506.01305

Shifting the Quantum-Classical Boundary: Theory and Experiment for Statistically Classical Optical Fields

Xiao-Feng Qian·Bethany Little·John C. Howell·J. H. Eberly
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Abstract

The growing recognition that entanglement is not exclusively a quantum property, and does not even originate with Schrödinger's famous remark about it [Proc. Camb. Phil. Soc. 31, 555 (1935)], prompts examination of its role in marking the quantum-classical boundary. We have done this by subjecting correlations of classical optical fields to new Bell-analysis experiments, and report here values of the Bell parameter greater than ${\cal B} = 2.54$. This is many standard deviations outside the limit ${\cal B} = 2$ established by the Clauser-Horne-Shimony-Holt (CHSH) Bell inequality [Phys. Rev. Lett. 23, 880 (1969)], in agreement with our theoretical classical prediction, and not far from the Tsirelson limit ${\cal B} = 2.828...$. These results cast a new light on the standard quantum-classical boundary description, and suggest a reinterpretation of it.

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Xiao-Feng Qian, Bethany Little, John C. Howell, J. H. Eberly. 2015-06-25. Shifting the Quantum-Classical Boundary: Theory and Experiment for Statistically Classical Optical Fields. https://doi.org/10.1364/optica.2.000611

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