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arXiv · 2212.03301

Classical model of quantum interferometry tests of macrorealism

Brian R. La Cour
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Abstract

Macrorealism is a characteristic feature of many, but not all, classical systems. It is known, for example, that classical light can violate a Leggett-Garg inequality and, hence, reject a macrorealist interpretation. A recent experiment has used entangled light and negative measurements to demonstrate a loophole-free test of macrorealism [PRX Quantum $\mathbf{3}$, 010307 (2022)]. This paper shows that such an experiment, while soundly rejecting macrorealism, may nevertheless be open to a classical interpretation. This is done by offering an explicit classical model of heralded photon detection in an optical interferometer with beam blockers. A numerical analysis of the model shows good agreement with experimental observations and consistency with both local realism and a rejection of macrorealism.

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Brian R. La Cour. 2022-12-06. Classical model of quantum interferometry tests of macrorealism. https://doi.org/10.1116/5.0131209

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