p-Branes and Exact solutions in Brans-Dicke cosmology with matter

TL;DR

This paper explores exact solutions in Brans-Dicke cosmology incorporating matter modeled as a gas of solitonic p-branes, revealing scenarios with no initial singularity and broadening understanding of string cosmology.

Contribution

It provides new analytic solutions for Brans-Dicke cosmology with p-brane matter, including cases free from initial singularities, extending previous models.

Findings

Some solutions are free from initial singularity.

Analytic solutions found for various equations of state.

Study covers a range of Brans-Dicke parameters.

Abstract

We study the effect of the solitonic degree of freedom in string cosmology following the line of Rama. The gas of solitonic p-brane is treated as a perfect fluid in a Brans-Dicke type theory. In this paper, we find analytic solutions for a few solvable cases of equation of states with general Brans-Dicke parameter $\omega$ and study the cosmology of the solutions. In some cases the solutions are free from initial singularity.