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arXiv · 1405.7439

Distinguishing de Sitter universe from thermal Minkowski spacetime by Casimir-Polder-like force

Zehua Tian·Jiliang Jing
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Abstract

We demonstrate that the static ground state atom, which interacts with a conformally coupled massless scalar field in the de Sitter invariant vacuum, can obtain a position-dependent energy-level shift and this shift could cause a Casimir-Polder-like force on it. Interestingly no such force arises on the inertial atom bathed in a thermal radiation in the Minkowski universe. Thus, although the energy-level shifts of the static atom for these two cases are structurally the same, whether the energy-level shift causes the Casimir-Polder-like force, in principle, could be as an indicator to distinguish de Sitter universe from the thermal Minkowski spacetime.

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Zehua Tian, Jiliang Jing. 2014-06-15. Distinguishing de Sitter universe from thermal Minkowski spacetime by Casimir-Polder-like force. https://doi.org/10.1007/jhep07(2014)089

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