Black hole thermodynamics has brought strong hints of a profound and fundamental connection between gravity, thermodynamics, and quantum theory. If the black hole does behave like a natural thermodynamic system, it should be thermodynamically stable in a clean environment. In this paper, using the observational data of binary black hole (BBH) mergers observed by LIGO, Virgo, and KAGRA detectors, we check whether the black hole remnants produced from BBH mergers in the LIGO-Virgo-KAGRA catalog GWTC-3 are thermodynamically stable. The criterion for the thermodynamic stability is quite simple and is directly related to the black hole's spin, which states that a thermodynamically stable black hole remnant requires its dimensionless spin $a>a_* \simeq 0.68$. We check the posterior distributions of final spin $a_f$ for 83 black hole remnants in GWTC-3 and find the whole remnant population is consistent with the thermodynamically stable black hole with $99.98\%$ probability. This is the first verification of the thermodynamic stability of black hole remnants produced from BBH mergers.
Remnant recoil and host environments of GWTC-4.0 binary black-hole mergers
Universitat de les Illes Balears（巴利阿里群岛大学）；Nicolaus Copernicus Astronomical Center, Polish Academy of Sciences（波兰科学院尼古拉·哥白尼天体物理中心）；University of Warsaw（华沙大学）；Max Planck Institute for Astrophysics（马克斯·普朗克天体物理学研究所）；Institut de Ciències de l’Espai (ICE, CSIC)（空间科学研究所（ICE，CSIC））
Analysis of GWTC-3 with fully precessing numerical relativity surrogate models
University of Massachusetts, Dartmouth（达特茅斯马萨诸塞大学）；The University of Auckland（奥克兰大学）；OzGrav: The ARC Centre of Excellence for Gravitational Wave Discovery（引力波发现ARC卓越中心）；University of Nevada, Las Vegas（内华达大学拉斯维加斯分校）；Nevada Center for Astrophysics（内华达天体物理学中心）；LIGO Laboratory, Massachusetts Institute of Technology（麻省理工学院LIGO实验室）；Massachusetts Institute of Technology（麻省理工学院）；Max Planck Institute for Gravitational Physics (Albert Einstein Institute)（马克斯·普朗克引力物理学研究所（爱因斯坦研究所））
GW231123: Likely a product of successive mergers from $\sim 10 $ stellar-mass black holes
Key Laboratory of Dark Matter and Space Astronomy, Purple Mountain Observatory, Chinese Academy of Sciences（暗物质和空间天文重点实验室，中国科学院紫金山天文台）；Department of Physics, University of Florida（佛罗里达大学物理系）；School of Astronomy and Space Science, University of Science and Technology of China（中国科学技术大学天文与空间科学学院）
Verification of the Black Hole Area Law with GW230814
Key Laboratory of Dark Matter and Space Astronomy, Purple Mountain Observatory, Chinese Academy of Sciences（中国科学院紫金山天文台暗物质与空间天文重点实验室）；School of Physics, Dalian University of Technology（大连理工大学物理学院）；School of Astronomy and Space Science, University of Science and Technology of China（中国科学技术大学天文与空间科学学院）
A new group of low-spin $50-70M_\odot$ Black Holes and the high pair-instability mass cutoff
Institute for Theoretical Physics and Cosmology, Zhejiang University of Technology（浙江工业大学理论物理与宇宙学研究所）；Key Laboratory of Dark Matter and Space Astronomy, Purple Mountain Observatory, Chinese Academy of Sciences（中国科学院紫金山天文台暗物质与空间天文重点实验室）；School of Astronomy and Space Science, Nanjing University（南京大学天文与空间科学学院）；School of Astronomy and Space Science, University of Science and Technology of China（中国科学技术大学天文与空间科学学院）
Smoking-gun evidence for hierarchical black-hole mergers
Key Laboratory of Dark Matter and Space Astronomy, Purple Mountain Observatory, Chinese Academy of Sciences（中国科学院紫金山天文台暗物质与空间天文重点实验室）；Institute for Theoretical Physics and Cosmology, Zhejiang University of Technology（浙江理工大学理论物理与宇宙学研究所）；School of Astronomy and Space Science, University of Science and Technology of China（中国科学技术大学天文与空间科学学院）
