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arXiv · 2503.23302

Genuine four-partite Bell nonlocality in the curved spacetime

Guang-Wei Mi·Xiaofen Huang·Shao-Ming Fei·Tinggui Zhang
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Abstract

The quantum Bell nonlocality plays a crucial role in quantum information processing. In this paper, we first obtain the quantitative analytical expression of the genuine four-partite Bell nonlocality of any 4-qubit quantum state. Then, we investigate and derive the genuine four-partite nonlocalities in the background of the Schwarzschild black hole and the Schwarzschild-de Sitter spacetime. In the Schwarzschild black hole, it is shown that the Hawking effect destroys the accessible genuine four-partite nonlocality while simultaneously having both detrimental and beneficial impacts on the inaccessible genuine four-partite nonlocality. Besides, we observe that the Hawking effect can generate the physically inaccessible genuine four-partite nonlocality for fermion fields in Schwarzschild black hole. This result shows that the genuine four-partite nonlocality can pass through the event horizon of black hole. Moreover, we also investigate the influence of the Hawking effect of the Schwarzschild-de Sitter spacetime on the genuine four-partite nonlocality of massless Dirac fields.

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Guang-Wei Mi, Xiaofen Huang, Shao-Ming Fei, Tinggui Zhang. 2025-03-30. Genuine four-partite Bell nonlocality in the curved spacetime. https://doi.org/10.1140/epjc%2Fs10052-025-14076-2

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