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arXiv · 2006.10084

Quantum time dilation in atomic spectra

Piotr T. Grochowski·Alexander R. H. Smith·Andrzej Dragan·Kacper Dębski
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Abstract

Quantum time dilation occurs when a clock moves in a superposition of relativistic momentum wave packets. We utilize the lifetime of an excited hydrogen-like atom as a clock to demonstrate how quantum time dilation manifests in a spontaneous emission process. The resulting emission rate differs when compared to the emission rate of an atom prepared in a mixture of momentum wave packets at order $v^2/c^2$. This effect is accompanied by a quantum correction to the Doppler shift due to the coherence between momentum wave packets. This quantum Doppler shift affects the spectral line shape at order $v/c$. However, its effect on the decay rate is suppressed when compared to the effect of quantum time dilation. We argue that spectroscopic experiments offer a technologically feasible platform to explore the effects of quantum time dilation.

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Piotr T. Grochowski, Alexander R. H. Smith, Andrzej Dragan, Kacper Dębski. 2020-06-17. Quantum time dilation in atomic spectra. https://doi.org/10.1103/physrevresearch.3.023053

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