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arXiv · 2502.20138

Fundamental Physics and Cosmology with TianQin

Jun Luo·Haipeng An·Ligong Bian·Rong-Gen Cai·Zhoujian Cao·Wenbiao Han·Jianhua He·Martin A. Hendry·Wencong Hong·Bin Hu·Yi-Ming Hu·Fa Peng Huang·Shun-Jia Huang·Sang Pyo Kim·En-Kun Li·Yu-Xiao Liu·Vadim Milyukov·Shi Pi·Konstantin Postnov·Misao Sasaki·Cheng-Gang Shao·Lijing Shao·Changfu Shi·Shuo Sun·Anzhong Wang·Pan-Pan Wang·Sai Wang·Shao-Jiang Wang·Zhong-Zhi Xianyu·Huan Yang·Tao Yang·Jian-dong Zhang·Xin Zhang·Wen Zhao·Liang-Gui Zhu·Jianwei Mei
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Abstract

The exploration of the surrounding world and the universe is an important theme in the legacy of humankind. The detection of gravitational waves is adding a new dimension to this grand effort. What are the fundamental physical laws governing the dynamics of the universe? What is the fundamental composition of the universe? How has the universe evolved in the past and how will it evolve in the future? These are the basic questions that press for answers. The space-based gravitational wave detector TianQin will tune in to gravitational waves in the millihertz frequency range ($10^{-4} \sim 1$ Hz, to be specific), opening a new gravitational wave spectrum window to explore many of the previously hidden sectors of the universe. TianQin will discover many astrophysical systems, populating the universe at different redshifts: some will be of new types that have never been detected before, some will have very high signal-to-noise ratios, and some will have very high parameter estimation precision. The plethora of information collected will bring us to new fronts on which to search for the breaking points of general relativity, the possible violation of established physical laws, the signature of possible new gravitational physics and new fundamental fields, and to improve our knowledge on the expansion history of the universe. In this white paper, we highlight the advances that TianQin can bring to fundamental physics and cosmology.

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Jun Luo, Haipeng An, Ligong Bian, Rong-Gen Cai, Zhoujian Cao, Wenbiao Han, Jianhua He, Martin A. Hendry, Wencong Hong, Bin Hu, Yi-Ming Hu, Fa Peng Huang, Shun-Jia Huang, Sang Pyo Kim, En-Kun Li, Yu-Xiao Liu, Vadim Milyukov, Shi Pi, Konstantin Postnov, Misao Sasaki, Cheng-Gang Shao, Lijing Shao, Changfu Shi, Shuo Sun, Anzhong Wang, Pan-Pan Wang, Sai Wang, Shao-Jiang Wang, Zhong-Zhi Xianyu, Huan Yang, Tao Yang, Jian-dong Zhang, Xin Zhang, Wen Zhao, Liang-Gui Zhu, Jianwei Mei. 2026-05-25. Fundamental Physics and Cosmology with TianQin. https://doi.org/10.1007/s41114-025-00063-2

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