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arXiv · 2205.05255

Sound from extra dimension: quasinormal modes of thick brane

Qin Tan·Wen-Di Guo·Yu-Xiao Liu
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Abstract

In this work, we investigate the quasinormal modes of a thick brane system. Considering the transverse-traceless tensor perturbation of the brane metric, we obtain the Schrödinger-like equation of the Kaluza-Klein modes of the tensor perturbation. Then we use the Wentzel-Kramers-Brillouin approximation and the asymptotic iteration method to solve this Schrödinger-like equation. We also study the numeric evolution of an initial wave packet against the thick brane. The results show that there is a set of discrete quasinormal modes in the thick brane model. These quasinormal modes appear as the decaying massive gravitons for a brane observer. They are characteristic modes of the thick brane and can reflect the structure of the thick brane.

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Qin Tan, Wen-Di Guo, Yu-Xiao Liu. 2024-02-20. Sound from extra dimension: quasinormal modes of thick brane. https://doi.org/10.1103/physrevd.106.044038

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