Exact anisotropic brane cosmologies

TL;DR

This paper derives exact anisotropic brane cosmology solutions within the Randall-Sundrum framework, analyzing their evolution with perfect fluids and scalar fields, and examining key observational parameters.

Contribution

It provides new exact solutions for anisotropic brane cosmologies with Bianchi geometries, including scalar field models and specific matter conditions, extending previous models.

Findings

Exact solutions for Bianchi type I and V brane universes.

Behavior of shear, anisotropy, and deceleration parameter analyzed.

Scalar field evolution models with various potentials considered.

Abstract

We present exact solutions of the gravitational field equations in the generalized Randall-Sundrum model for an anisotropic brane with Bianchi type I and V geometry, with perfect fluid and scalar fields as matter sources. Under the assumption of a conformally flat bulk (with vanishing Weyl tensor) for a cosmological fluid obeying a linear barotropic equation of state the general solution of the field equations can be expressed in an exact parametric form for both Bianchi type I and V space-times. In the limiting case of a stiff cosmological fluid with pressure equal to the energy density, for a Bianchi type I Universe the solution of the field equations are obtained in an exact analytic form. Several classes of scalar field models evolution on the brane are also considered, corresponding to different choices of the scalar field potential. For all models the behavior of the observationally important parameters like shear, anisotropy and deceleration parameter is considered in detail.