On brane cosmological solutions

TL;DR

This paper explores the cosmological implications of a five-dimensional two-brane Randall-Sundrum model, showing that the universe undergoes power-law expansion with scale factor proportional to t^{1/2} and that the branes move closer over time.

Contribution

It analyzes the cosmology of a time-dependent extra dimension in the two-brane Randall-Sundrum scenario, highlighting the power-law expansion and brane dynamics.

Findings

Universe expands as t^{1/2} in this model

The two branes tend to approach each other over time

Surface terms influence the four-dimensional effective action

Abstract

This paper presents some cosmological consequences of the five dimensional, two brane Randall-Sundrum brane scenario. The radius of the compact extra dimension is taken to be time dependent. It is shown that the cosmology consistent with the two brane Randall-Sundrum model is a power law expansion of the universe, with scale factor growing as $t^{1/2}$. The two branes tend to move towards each other with time. Some comments are made on the contribution of surface terms in deriving the four dimensional effective action.