Integrable mass of Kerr-Newman-Bertotti-Robinson black hole

@misc{hu2026integrable,
  title = {{Integrable mass of Kerr-Newman-Bertotti-Robinson black hole}},
  author = {Li Hu and Rong-Gen Cai and Shan-Wen Jiang and Shao-Jiang Wang},
  howpublished = {arXiv},
  year = {2026},
  month = nov,
  doi = {10.48550/arxiv.2611.03123},
  eprint = {2611.03123},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/2611.03123},
}

TY  - UNPB
TI  - Integrable mass of Kerr-Newman-Bertotti-Robinson black hole
AU  - Li Hu
AU  - Rong-Gen Cai
AU  - Shan-Wen Jiang
AU  - Shao-Jiang Wang
PY  - 2026
DA  - 2026/11/02
PB  - arXiv
DO  - 10.48550/arxiv.2611.03123
UR  - https://arxiv.org/abs/2611.03123
AB  - The nontrivial asymptotic structure of rotating black holes in the Bertotti-Robinson universe complicates a direct determination of their conserved mass, leading previous studies to rely on a priori thermodynamic input. We address this long-standing problem using integrability methods, establish local analytic existence and uniqueness via the Cauchy-Kovalevskaja theorem, and obtain a closed expression via a rescaled recurrence whose termination is proved at all orders. The resulting Kerr-Newman-Bertotti-Robinson mass coincides with the expression previously derived using the canonical first law identity and reproduces the masses of both Kerr-Bertotti-Robinson subcases. With the mass thus fixed without invoking thermodynamic relations for the first time, we rigorously establish the first law of black-hole thermodynamics and the Smarr formula for a whole family of Kerr-Bertotti-Robinson black holes suitable for future applications.
ER  -