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arXiv · 2610.35096

Quasinormal modes of thick branes in $f(R,T)$ gravity

Yu-Peng E·Hai-Long Jia·Chun-Chun Zhu
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Abstract

We study tensor perturbations and quasinormal modes (QNMs) of thick branes in $f(R,T)=R+αT$ gravity. Starting from the background thick brane solutions, we derive the Schrödinger-like equation for gravitational perturbations and construct the corresponding effective potential. The effective potential exhibits a double-barrier structure whose properties depend on the model parameters. We analyze transmission spectra and find good agreement between resonance peaks and the real parts of the quasinormal frequencies. The parameters $b$ and $α$ mainly control the width and height of the potential barriers, respectively. QNMs are extracted using both time-domain evolution and direct integration methods, showing consistent results for low-lying modes. Higher overtones become increasingly difficult to extract due to stronger damping and numerical contamination. Our results indicate that $f(R,T)$ corrections significantly affect both the effective potential and the quasinormal spectrum, providing a possible imprint of modified gravity in braneworld perturbations.

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Yu-Peng E, Hai-Long Jia, Chun-Chun Zhu. 2026-10-26. Quasinormal modes of thick branes in $f(R,T)$ gravity. https://arxiv.org/abs/2610.35096

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