The extension method for Bloch branes

Abstract

The nature of gravity and its strength compared with other forces are fundamental challenges faced by the actual science. A path to understand the hierarchy problem of gravity consists in adding an extra dimension to Einstein–Hilbert’s general relativity. Therefore, gravity would be the only force leaking through this region of space–time also known as brane. Despite the success of the mathematical description for the hierarchy issue through simple thin branes, it is also possible to derive a consistent theory of gravity using thick branes. This work unveils a new procedure to determine analytic hybrid thick braneworld models. The discussions were based on the so-called Bloch branes, which are constructed via a two-field model coupled with gravity in five-dimensional space–time. Both fields used to build the Bloch branes depend only on the extra dimension, and the hybrid branes present internal structure, characterizing them as thick. In this work, we were able to derive new analytic thick brane models by using the extension method. Some of these new branes present a Minkowski space–time immersed inside of the fifth dimension. We showed how the symmetry of the emergent branes can be controlled via specific parameters. We also analyzed the stability conditions for each braneworld family, showing possible stable states for gravitons.