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arXiv · 2112.02759

Testing gravitational redshift based on microwave frequency links onboard China Space Station

Wenbin Shen·Pengfei Zhang·Ziyu Shen·Rui Xu·Xiao Sun·Mostafa Ashry·Abdelrahim Ruby·Wei Xu·Kuangchao Wu·Yifan Wu·An Ning·Lei Wang·Lihong Li·Chenghui Cai
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Abstract

In 2022 China Space Station (CSS) will be equipped with atomic clocks and optical clocks with stabilities of $2 \times 10^{-16}$ and $8 \times 10^{-18}$, respectively, which provides an excellent opportunity to test gravitational redshift (GR) with higher accuracy than previous results. Based on high-precise frequency links between CSS and a ground station, we formulated a model and provided simulation experiments to test GR. Simulation results suggest that this method could test the GR at the accuracy level of $(0.27 \pm 2.15) \times10^{-7}$, more than two orders in magnitude higher than the result of the experiment of a hydrogen clock on board a flying rocket more than 40 years ago.

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Wenbin Shen, Pengfei Zhang, Ziyu Shen, Rui Xu, Xiao Sun, Mostafa Ashry, Abdelrahim Ruby, Wei Xu, Kuangchao Wu, Yifan Wu, An Ning, Lei Wang, Lihong Li, Chenghui Cai. 2021-12-06. Testing gravitational redshift based on microwave frequency links onboard China Space Station. https://arxiv.org/abs/2112.02759

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