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arXiv · 2311.02867

Violation of the two-time Leggett-Garg inequalities for a coarse-grained quantum field

Masaki Tani·Kosei Hatakeyama·Daisuke Miki·Yuki Yamasaki·Kazuhiro Yamamoto
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Abstract

We investigate the violation of the Leggett-Garg inequalities for a quantum field, focusing on the two-time quasi-probability distribution function of the dichotomic variable with a coarse-grained scalar field. The Leggett-Garg inequalities are violated depending on the quantum state of the field and the size of coarse-graining. We also demonstrate that the violation of the Leggett-Garg inequalities appears even for the vacuum state and the squeezed state by properly constructing the dichotomic variable and the projection operator.

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Masaki Tani, Kosei Hatakeyama, Daisuke Miki, Yuki Yamasaki, Kazuhiro Yamamoto. 2023-11-06. Violation of the two-time Leggett-Garg inequalities for a coarse-grained quantum field. https://arxiv.org/abs/2311.02867

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