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Predictions on observing hot holographic quark stars with gravitational waves

Le-Feng Chen1,*, Heng-Yi Yuan1,†, Meng-Hua Zhou1,‡, Kun Lu1,§, Jing-Yi Wu2,∥, and Kilar Zhang1,3,4,¶

  • *Contact author: clf@shu.edu.cn
  • †Contact author: natalie1225@shu.edu.cn
  • ‡Contact author: ywzmhatd@shu.edu.cn
  • §Contact author: 2858446139@shu.edu.cn
  • ∥Contact author: wujingyi222@mails.ucas.ac.cn
  • Contact author: kilar@shu.edu.cn
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Phys. Rev. D 112, 123020 – Published 9 December, 2025

DOI: https://doi.org/10.1103/n4m8-yjzl

Abstract

We extract the equation of state of hot quark matter from a holographic 2+1 flavor quantum chromodynamics (QCD) model, which could form the core of a stable compact star. By adding a thin hadron shell, a new type of hybrid star is constructed. With the temperature serving as a parameter, the EoS varies and we obtain stable stars with mass ranging from about 5 to 30 solar masses, and the maximum compactness around 0.2. The I-Love-Q-C relations are further discussed, and compared with the neutron star cases. These compact stars are candidates for black hole mimickers, which could be observed by gravitational waves and distinguished by properties like nonzero tidal Love number and electromagnetic signals.

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Phys. Rev. D 112, 123020– Published 9 December, 2025
  • Received 29 August 2025
  • Accepted 26 November 2025
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