Initial singularity free quantum cosmology in two-dimensional Brans-Dicke theory

TL;DR

This paper investigates how quantum effects in two-dimensional Brans-Dicke cosmology can resolve the initial singularity, leading to finite curvature and gravitational coupling at the universe's origin for specific parameter choices.

Contribution

It demonstrates that quantum back reaction can eliminate initial singularities in 2D Brans-Dicke models for certain Brans-Dicke constants, a novel insight into quantum cosmology.

Findings

Initial curvature singularity can be finite due to quantum effects.

For ω=1, universe begins with finite curvature and evolves into flat spacetime.

Quantum corrections can make gravitational coupling finite at initial time.

Abstract

We consider two-dimensional Brans-Dicke theory to study the initial singularity problem. It turns out that the initial curvature singularity can be finite for a certain Brans-Dicke constant $\omega$ by considering the quantum back reaction of the geometry. For $\omega=1$, the universe starts with the finite curvature scalar and evolves into the flat spacetime. Furthermore the divergent gravitational coupling at the initial time can be finite effectively with the help of quantum correction. The other type of universe is studied for the case of $0<\omega<1$.