Dark Energy in Global Brane Universe

TL;DR

This paper explores how modifications to Friedmann equations in brane universe models can account for dark energy, analyzing its evolution with red-shift using Wetterich's EOS parametrization.

Contribution

It introduces a new density term in brane cosmology equations as dark energy and studies its red-shift dependence and impact on universe evolution.

Findings

The new density term varies with red-shift z.

Dark energy density parameter $\

Omega_x$ evolves with red-shift and influences cosmic acceleration.

Abstract

We discuss the exact solutions of brane universes and the results indicate the Friedmann equations on the branes are modified with a new density term. Then, we assume the new term as the density of dark energy. Using Wetterich's parametrization equation of state (EOS) of dark energy, we obtain the new term varies with the red-shift z. Finally, the evolutions of the mass density parameter $\Omega_2$, dark energy density parameter $\Omega_x$ and deceleration parameter q_2 are studied.