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arXiv · 1707.02318

Limits on Lorentz violation in gravity from worldwide superconducting gravimeters

Cheng-Gang Shao·Ya-Fen Chen·Rong Sun·Lu-Shuai Cao·Min-Kang Zhou·Zhong-Kun Hu·Chenghui Yu·Holger Müller
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Abstract

We investigated Lorentz violation through anisotropy of gravity using a worldwide array of 12 superconducting gravimeters. The Lorentz-violating signal is extracted from the difference between measured gravity and a tidal model. At the level of sensitivity we reach, ocean tides start to play an important role. However, most models available that include ocean tides are empirically based on measured gravity data, which may contain Lorentz-violating signal. In this work we used an ocean tides included tidal model derived from first principles to extract Lorentz-violating signal for the first time. We have bounded space-space components of gravitational Lorentz violation in the minimal standard model extension (SME) up to the order of $10^{-10}$, one order of magnitude improved relative to previous atom-interferometer tests.

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Cheng-Gang Shao, Ya-Fen Chen, Rong Sun, Lu-Shuai Cao, Min-Kang Zhou, Zhong-Kun Hu, Chenghui Yu, Holger Müller. 2017-07-07. Limits on Lorentz violation in gravity from worldwide superconducting gravimeters. https://doi.org/10.1103/physrevd.97.024019

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