de Sitter branes with a bulk scalar

Abstract

We propose new braneworld models arising from a scalar field in the bulk. In these examples, the induced on--brane line element is de Sitter (or anti de Sitter) and the bulk (five dimensional) Einstein equations can be exactly solved to obtain warped spacetimes. The solutions thus derived are single and two-brane models -- one with {\em thin} branes while the other one of the {\em thick} variety. The field profiles and the potentials are obtained and analysed for each case. We note that for the {\em thick} brane scenario the field profile resembles a kink, whereas for one or more {\em thin} branes, it is finite and bounded in the domain of the extra dimension. We have also addressed the localisation of gravity and other matter fields on the brane for these braneworld models.