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arXiv · 1802.01454

Linear Stability of $f(R,\phi,X)$ Thick Branes: Tensor Perturbations

Zheng-Quan Cui·Yu-Xiao Liu·Bao-Min Gu·Li Zhao
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Abstract

We explore thick branes in $f(R,\phi,X)$ gravity. We obtain the linear tensor perturbation equation of $f(R,\phi,X)$ branes and show that the branes are stable against the tensor perturbations under the condition of $\frac{\partial f(R,\phi,X)}{\partial R}>0$. In order to obtain thick brane solutions of the fourth-order field equations in this theory, we employ the reconstruction technique. We get exact solutions of the specific $f(R,\phi,X)$ thick brane generated by a non-canonical scalar field. It is shown that the zero mode of the graviton for the thick brane is localized under certain conditions. This implies that the four-dimensional Newtonian potential is recovered on the brane. The effects of the Kaluza-Klein modes of the graviton for the $f(R,\phi,X)$ thick brane are also discussed.

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Zheng-Quan Cui, Yu-Xiao Liu, Bao-Min Gu, Li Zhao. 2018-02-05. Linear Stability of $f(R,\phi,X)$ Thick Branes: Tensor Perturbations. https://doi.org/10.1007/jhep11(2018)083

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