Flat and bent branes with inner structure in two-field mimetic gravity

TL;DR

This paper investigates the stability and resonant modes of flat and bent thick branes with inner structure in two-field mimetic gravity, revealing volcano-like potentials and the existence of zero and resonant modes.

Contribution

It provides a detailed analysis of tensor perturbations in two-field mimetic gravity branes, including stability conditions and the structure of resonant modes, extending previous work to more complex brane configurations.

Findings

Brane systems are stable against tensor perturbations.

Effective potentials are volcano-like, supporting zero and resonant modes.

Identification of massive resonant modes in the brane models.

Abstract

Inspired by the work [Eur. Phys. J. C 78 (2018) 45], we study the linear tensor perturbation of both the flat and bent thick branes with inner structure in two-field mimetic gravity. The master equations for the linear tensor perturbations are derived by taking the transverse and traceless gauge. For the Minsowskii and Anti-de-Sitter brane, the brane systems are stable against the tensor perturbation. The effective potentials of the tensor perturbations of both the flat and bent thick branes are volcano-like, and this structure may potentially lead to the zero-mode and the resonant modes of the tensor perturbation. We further illustrate the results of massive resonant modes.