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arXiv · 1605.07350

Detecting the Curvature of de Sitter Universe with Two Entangled Atoms

Zehua Tian·Jieci Wang·Jiliang Jing·Andrzej Dragan
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Abstract

Casimir-Polder interaction arises from the vacuum fluctuations of quantum field that depend on spacetime curvature and thus is spacetime-dependent. Here we show how to use the resonance Casimir-Polder interaction (RCPI) between two entangled atoms to detect spacetime curvature. We find that the RCPI of two static entangled atoms in the de Sitter-invariant vacuum depends on the de Sitter spacetime curvature relevant to the temperature felt by the static observer. It is characterized by a $1/L^2$ power law decay when beyond a characteristic length scale associated to the breakdown of a local inertial description of the two-atom system. However, the RCPI of the same setup embedded in a thermal bath in the Minkowski universe is temperature-independent and is always characterized by a $1/L$ power law decay. Therefore, although a single static atom in the de Sitter-invariant vacuum responds as if it were bathed in thermal radiation in a Minkowski universe, using the distinct difference between RCPI of two entangled atoms one can in principle distinguish these two universes.

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Zehua Tian, Jieci Wang, Jiliang Jing, Andrzej Dragan. 2016-05-24. Detecting the Curvature of de Sitter Universe with Two Entangled Atoms. https://doi.org/10.1038/srep35222

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