Accelerating universe in brane gravity with a confining potential

Abstract

We construct the Einstein field equations on a 4-dimensional brane embedded in an $m$-dimensional bulk where the matter fields are confined to the brane by means of a confining potential. As a result, an extra term in the Friedmann equation in a $m$-dimensional bulk appears that may be interpreted as the X-matter, providing a possible phenomenological explanation for the acceleration of the universe. The study of the relevant observational data suggests good agreement with the predictions of this model.Comment: 10 pages, 2 figures, to appear in Phys. Lett.

Generalized Chaplygin gas as geometrical dark energy

“…In this section we present a brief review of the model proposed in [19,21]. Consider the background manifold V 4 isometrically embedded in a pseudo-Riemannian manifold V m by the map Y :…”

Constraints on cosmokinetics of smooth deformations

“…[12,36,38,11,21,10,5,22,24,18]. In spite of such efforts we still do not have a complete model independent solution for the present cosmological problems [15].…”

Gauss-Bonnet brane gravity with a confining potential

“…(72) The results are summarized in table 1. It shows that the age of the universe in our model is longer than the FRW model and brane models without the Gauss-Bonnet term in the bulk action [17].…”

“…Also a phenomenological explanation based on current observational data is given by the X-matter model which is associated with an exotic fluid characterized by an equation of state p x = w x ρ x , where the parameter w x can be a constant or more generally a function of time [27]. In this section, following the method developed in [17], we show that within the context of the present model, it is possible to have a universe exhibiting accelerated expansion without the need to resort to a cosmological constant term or a scalar field or any other kind of dark energy. Let us proceed by taking equations (57) and (58) from which, the Hubble parameter can be written as…”