Cosmic Evolution in Self-Interacting Brans-Dicke Cosmology

TL;DR

This paper explores how self-interacting potentials in Brans-Dicke cosmology can explain the universe's accelerated expansion, analyzing scalar field dynamics and perturbations in a Bianchi type I universe model.

Contribution

It introduces a model with a power law scalar field and potential in Brans-Dicke theory, showing conditions for accelerated expansion and perturbation growth.

Findings

Accelerated expansion occurs for positive power law potential with negative BD parameter.

Energy density perturbations exhibit growing modes for negative BD parameter and positive scalar field exponent.

The model aligns with observational indications of cosmic acceleration.

Abstract

In this paper, we investigate the nature of self-interacting potential that can support the accelerated expansion of the universe as indicated by observational data. For this purpose, we consider the Bianchi type I (BI) universe model in the Brans-Dicke (BD) field scenario and use a power law for both the scalar field and the scale factor. It is found that the accelerated expansion of the universe can be discussed for a positive power law potential with negative values of the BD parameter. We also explore the evolution of energy density perturbations. This analysis indicates that the model allows growing modes for negative values of the BD parameter and $m>0$.