Localization of scalar field on f(R, T) thick Robertson-Walker brane

Abstract

The braneworld model provides a solution to the hierarchy problem in cosmology. Based on its thickness, braneworld models are classified into a thin brane model (RandallSundrum (RS) and the RS-like models) and a thick brane model. The thin brane model has a problem according to the zero-width brane and some fields localization. Meanwhile, thick brane is quite good in explaining fields localization and there is no problem related to brane thickness. In this article, we re-examine the thick brane in a modified gravity, that is f(R,T) gravity. The equation of motion for the y-dependence scalar field and the f(R,T) field equation for a conformally flat brane and Robertson-Walker brane are derived. We also investigate the localization of scalar field on the f(R,T) thick brane, for a specific f(R,T) form. As the results, the formulation of Robertson-Walker thick brane is obtained. It can be reduced and has similarities to the previous f(R,T) brane consideration. It has a possibility to trap the field ϕ(y) in a thick brane with specific conditions of brane’s scale factor. It was shown that the expanding or contracting universe affects the localization conditions of the scalar fields.