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arXiv · 2508.19178

Gravitational perturbations of the Hayward spacetime and testing the correspondence between quasinormal modes and grey-body factors

Zainab Malik
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Abstract

The paper studies axial gravitational perturbations of the Hayward black hole, a regular geometry that also arises as an effective solution in asymptotically safe gravity. By computing grey-body factors with the 6th-order WKB method and comparing them to predictions based on the quasinormal modes, the correspondence between transmission coefficients and quasinormal spectra is verified. Quantum corrections, parametrized by $\gamma$, are shown to suppress both the grey-body factors and the absorption cross-section, while the correspondence remains accurate at the percent level for low multipoles and essentially exact for higher ones.

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Zainab Malik. 2025-08-26. Gravitational perturbations of the Hayward spacetime and testing the correspondence between quasinormal modes and grey-body factors. https://doi.org/10.1007/s10773-025-06198-w

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