Tidal Deformation and Strain Accumulation of Solid Compact Stars
5 affiliations
- 1School of Physics, Peking University , Beijing 100871 ,
- 2Max Planck Institute for Gravitational Physics (Albert Einstein Institute) , 14476 Potsdam ,
- 3Kavli Institute for Astronomy and Astrophysics , Peking University, Beijing 100871 ,
- 4State Key Laboratory of Nuclear Physics and Technology , Peking University, Beijing 100871 ,
- 5School of Physics, Peking University Department of Astronomy, , Beijing 100871 ,
Abstract
The tidal deformability of compact stars encodes the equation of state of dense matter, and gravitational-wave observations such as GW170817 have begun to constrain it under the assumption of a fluid interior. Yet whether the interior of pulsar-like compact stars is fluid or solid remains largely untested, despite the distinct tidal responses the two states predict. In this work, based on the strangeon-star model, we develop a framework for modeling tidal deformation in solid compact stars. Adopting a shear modulus of μ = 1034 erg cm−3, we find a relative difference of approximately 30 % in tidal deformability between solid and fluid strangeon stars of 1.4 M⊙, corresponding to a ~10 % deviation from the universal I–Love relation. We further model the accumulation of internal strain during binary inspiral and find that it peaks near the stellar center. When the gravitational-wave frequency reaches several hundred Hz, the strain in a large fraction of the stellar volume exceeds the adopted threshold σ = 10−3, and the elastic energy stored in the threshold-exceeding region reaches ~1046 erg at these frequencies. A solid-to-fluid transition would alter the tidal response and could imprint on the waveform and phase of the emitted gravitational radiation. Combined with the precursor electromagnetic emission, these gravitational-wave signatures offer a multi-messenger avenue to test the solid nature of pulsar-like compact stars.
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BibTeX
@article{shen2026tidal,
title = {{Tidal Deformation and Strain Accumulation of Solid Compact Stars}},
author = {Hongxiang Shen and Yong Gao and Hong-Bo Li and Ren-Xin Xu},
journal = {Monthly Notices of the Royal Astronomical Society},
year = {2026},
month = nov,
doi = {10.1093/mnras/stag2059},
url = {https://academic.oup.com/mnras/advance-article/doi/10.1093/mnras/stag2059/9012726},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Tidal Deformation and Strain Accumulation of Solid Compact Stars
AU - Hongxiang Shen
AU - Yong Gao
AU - Hong-Bo Li
AU - Ren-Xin Xu
PY - 2026
DA - 2026/11/04
JO - Monthly Notices of the Royal Astronomical Society
DO - 10.1093/mnras/stag2059
UR - https://academic.oup.com/mnras/advance-article/doi/10.1093/mnras/stag2059/9012726
AB - The tidal deformability of compact stars encodes the equation of state of dense matter, and gravitational-wave observations such as GW170817 have begun to constrain it under the assumption of a fluid interior. Yet whether the interior of pulsar-like compact stars is fluid or solid remains largely untested, despite the distinct tidal responses the two states predict. In this work, based on the strangeon-star model, we develop a framework for modeling tidal deformation in solid compact stars. Adopting a shear modulus of μ = 1034 erg cm−3, we find a relative difference of approximately 30 % in tidal deformability between solid and fluid strangeon stars of 1.4 M⊙, corresponding to a ~10 % deviation from the universal I–Love relation. We further model the accumulation of internal strain during binary inspiral and find that it peaks near the stellar center. When the gravitational-wave frequency reaches several hundred Hz, the strain in a large fraction of the stellar volume exceeds the adopted threshold σ = 10−3, and the elastic energy stored in the threshold-exceeding region reaches ~1046 erg at these frequencies. A solid-to-fluid transition would alter the tidal response and could imprint on the waveform and phase of the emitted gravitational radiation. Combined with the precursor electromagnetic emission, these gravitational-wave signatures offer a multi-messenger avenue to test the solid nature of pulsar-like compact stars.
SN - 0035-8711
SN - 1365-2966
ER -