English

Quasinormal modes of Kerr-like black bounce spacetime

General Relativity and Quantum Cosmology 2025-12-30 v2

Abstract

We investigate the quasinormal mode (QNM) spectrum of a Kerr-like black-bounce spacetime under massive scalar-field perturbations. Starting from the Kerr-like deformation of the Simpson--Visser black-bounce geometry, we derive the corresponding radial and angular equations and obtain the effective potential governing scalar perturbations. We show that the Kerr-like black-bounce spacetime inherits a characteristic double-peaked effective potential, analogous to the Schwarzschild-like black-bounce case, which is known to be associated with late-time echo signals. The QNM frequencies are computed by means of the P\"oschl--Teller potential approximation and the semi-analytic WKB method (up to sixth order), and we demonstrate good agreement between these two approaches. We then analyze in detail how the QNM spectrum depends on the spin parameter aa, the bounce parameter pp that interpolates between black-hole and wormhole geometries, and the scalar-field mass μ\mu. Our results indicate that increasing either aa or pp lowers both the real frequency and the magnitude of the imaginary part, leading to longer-lived modes. Moreover, the mass of the scalar field has a non-negligible impact on the ringdown spectrum. These features suggest that rotating black-bounce geometries may leave distinct imprints in the ringdown phase of gravitational-wave signals, and motivate future studies of echoes and parameter estimation in the context of present and upcoming detectors.

Keywords

Cite

@article{arxiv.2205.07530,
  title  = {Quasinormal modes of Kerr-like black bounce spacetime},
  author = {Yi Yang and Dong Liu and Ali Övgün and Zheng-Wen Long and Zhaoyi Xu},
  journal= {arXiv preprint arXiv:2205.07530},
  year   = {2025}
}