Time Dependence of Brans-Dicke Parameter w for an Expanding Universe

TL;DR

This paper investigates how the Brans-Dicke parameter w varies over time in an expanding universe, considering different matter contents, and explores its implications for the observed accelerated cosmic expansion.

Contribution

It provides an explicit formulation of w's time dependence in the generalized Brans-Dicke theory across different cosmic eras.

Findings

w's explicit dependence on matter type and era

Potential explanation for accelerated expansion within the formalism

Insights into scalar-tensor theories in cosmology

Abstract

We have studied the time dependence of w for an expanding universe in the generalised B-D theory and have obtained its explicit dependence on the nature of matter contained in the universe,in different era.Lastly we discuss how the observed accelerated expansion of the present universe can be accomodated in the formalism.