Phys.Rev.D, 111, 044003 (2025)
Charging the Love numbers: Charged scalar response coefficients of Kerr-Newman black holes
Liang Ma1, Ze-Hua Wu1, Yi Pang1,2 and Hong Lu1,2,3
1 Center for Joint Quantum Studies, Department of Physics, School of Science, Tianjin University, Tianjin 300350, China.
2 Peng Huanwu Center for Fundamental Theory, Hefei, Anhui 230026, China.
3 Joint School of National University of Singapore and Tianjin University, International Campus of Tianjin University, Binhai New City, Fuzhou 350207, China.
* liangma_physics_0@tju.edu.cn, wuzh_2022@tju.edu.cn, pangyi1@tju.edu.cn, mrhonglu@gmail.com
Abstract
We study the electrically charged massless scalar response to the general Kerr-Newman black hole and obtain the exact (complex) response coefficients, whose real parts are the Love numbers. We find there is a curious discontinuity between the neutral and charged scalar. The Love numbers vanish for the neutral scalar, but are inversely proportional to the electric charge of the scalar in the small charge limit. We also generalize the results into higher dimensions to some extend.
