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TESTING March 24, 2026

In-orbit Test of the Weak Equivalence Principle with Atom Interferometry

Authors

Dan-Fang Zhang, Jing-Ting Li, Wen-Zhang Wang, Wei-Hao Xu, Jia-Yi Wei, Xiao Li, Yi-Bo Wang, Dong-Feng Gao, Jia-Qi Zhong, Biao Tang, Lin Zhou, Run-Bing Li, Huan-Yao Sun, Qun-Feng Chen, Lei Qin, Mei-zhen An, Zong-Feng Li, Shu-Quan Wang, Xiao-Xiao Guo, Yao Tian, Xi-He Yu, Hong-En Zhong, Xi Chen, Jin Wang, Ming-Sheng Zhan

Abstract

The Weak Equivalence Principle (WEP) is a central pillar of general relativity. Its precise test with quantum systems in space offers a unique window onto new physics. Here we report the first in-orbit quantum test of the WEP. A dual-species (85Rb/87Rb) atom interferometer is realized aboard the China Space Station. Methods of platform motion suppression, fluorescence detection switching, and two-photon detuning switching are developed to eliminate phase noise and improve measurement accuracy. A test uncertainty of 2.8*10-8 is obtained from 280 days of WEP test data, and a test result of (-3.1+/-4.6)*10-7 is achieved after error estimation. This improves prior atom-interferometric WEP tests in microgravity by three orders of magnitude. This work paves the way for space-borne quantum inertial sensors and their application to future fundamental physics in space.

Metadata

arXiv ID: 2603.22981
Provider: ARXIV
Primary Category: physics.atom-ph
Published: 2026-03-24
Fetched: 2026-03-25 06:02

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