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arXiv · 1907.00715

Spontaneous excitation of an accelerated atom coupled with quantum fluctuations of spacetime

Shijing Cheng·Jiawei Hu·Hongwei Yu
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Abstract

A direct consequence of quantization of gravity would be quantum gravitational vacuum fluctuations which induce quadrupole moments in gravitationally polarizable atoms. In this paper, we study the spontaneous excitation of a gravitationally polarizable atom with a uniform acceleration $a$ in interaction with a bath of fluctuating quantum gravitational fields in vacuum, and compare the result with that of a static one in a thermal bath of gravitons at the Unruh temperature. We find that, under the fluctuations of spacetime itself, transitions to higher-lying excited states from the ground state are possible for both the uniformly accelerated atom in vacuum and the static one in a thermal bath. The appearance of terms in the transition rates proportional to $a^4$ and $a^2$ indicates that the equivalence between uniform acceleration and thermal field is lost.

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Shijing Cheng, Jiawei Hu, Hongwei Yu. 2019-07-01. Spontaneous excitation of an accelerated atom coupled with quantum fluctuations of spacetime. https://doi.org/10.1103/physrevd.100.025010

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