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arXiv · 2307.04409

Violation of a Leggett-Garg inequality using ideal negative measurements in neutron interferometry

Elisabeth Kreuzgruber·Richard Wagner·Niels Geerits·Hartmut Lemmel·Stephan Sponar
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Abstract

We report on an experiment that demonstrates the violation of a Leggett-Garg inequality (LGI) with neutrons. LGIs have been proposed in order to assess how far the predictions of quantum mechanics defy macroscopic realism. With LGIs, correlations of measurements performed on a single system at different times are described. The measured value of K = 1.120 +/- 0.007, obtained in a neutron interferometric experiment, is clearly above the limit K = 1 predicted by macro-realistic theories.

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Elisabeth Kreuzgruber, Richard Wagner, Niels Geerits, Hartmut Lemmel, Stephan Sponar. 2023-07-10. Violation of a Leggett-Garg inequality using ideal negative measurements in neutron interferometry. https://doi.org/10.1103/physrevlett.132.260201

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