• Corpus ID: 244714234

Leggett-Garg inequalities for testing quantumness of gravity

@inproceedings{Matsumura2021LeggettGargIF,
  title={Leggett-Garg inequalities for testing quantumness of gravity},
  author={Akira Matsumura and Yasusada Nambu and Kazuhiro Yamamoto},
  year={2021}
}

• Akira Matsumura, Y. Nambu, Kazuhiro Yamamoto
• Published 28 November 2021
• Physics

In this study, we determine a violation of the Leggett-Garg inequalities due to gravitational interaction in a hybrid system consisting of a harmonic oscillator and a spatially localized superposed particle. The violation of the Leggett-Garg inequalities is discussed using the two-time quasiprobability in connection with the entanglement negativity generated by gravitational interaction. It is demonstrated that the entanglement suppresses the violation of the Leggett-Garg inequalities when one of the two times of the quasiprobability t1 is chosen as the initial time. Further, it is shown that the Leggett-Garg inequalities are generally violated due to gravitational interaction by properly choosing the configuration of the parameters, including t1 and t2, which are the times of the two-time quasiprobability. The feasibility of detecting violations of the Leggett-Garg inequalities in hybrid systems is also discussed.