European Physical Journal C: Particles and Fields (Aug 2021)
Thick branes with inner structure in mimetic f(R) gravity
Abstract
Abstract In this paper, we study the structure and gravitational resonances of thick branes generated by a mimetic scalar field in f(R) gravity. We obtain several typical thick brane solutions for $$f(R)=R+\alpha R^2$$ f ( R ) = R + α R 2 . To study their stability, we analyze the tensor perturbation of the metric. It is shown that any thick brane model with $$df/dR>0$$ d f / d R > 0 is stable and the graviton zero mode can be localized on the brane for each solution, which indicates that the four-dimensional Newtonian gravity can be restored. The effect of the parameter $$\alpha $$ α on the gravitational resonances is studied. As a brane splits into multi sub-branes, the effective potential of the tensor perturbation will have an abundant inner structure with multi-wells, and this will lead to new phenomena of the gravitational resonances.