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arXiv · 2004.03392

Quantum-classical hypothesis tests in macroscopic matter-wave interferometry

Björn Schrinski·Stefan Nimmrichter·Klaus Hornberger
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Abstract

We assess the most macroscopic matter-wave experiments to date as to the extent to which they probe the quantum-classical boundary by demonstrating interference of heavy molecules and cold atomic ensembles. To this end, we consider a rigorous Bayesian test protocol for a parametrized set of hypothetical modifications of quantum theory, including well-studied spontaneous collapse models, that destroy superpositions and reinstate macrorealism. The range of modification parameters ruled out by the measurement events quantifies the macroscopicity of a quantum experiment, while the shape of the posterior distribution resulting from the Bayesian update reveals how conclusive the data are at testing macrorealism. This protocol may serve as a guide for the design of future matter-wave experiments ever closer to truly macroscopic scales.

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Björn Schrinski, Stefan Nimmrichter, Klaus Hornberger. 2020-04-07. Quantum-classical hypothesis tests in macroscopic matter-wave interferometry. https://doi.org/10.1103/physrevresearch.2.033034

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