On the fate of the phantom dark energy universe in semiclassical gravity II: Scalar phantom fields

TL;DR

This paper investigates whether quantum corrections from conformally coupled massless fields can prevent the Big Rip singularity in a universe dominated by scalar phantom dark energy, extending previous fluid-based models.

Contribution

It analyzes the impact of quantum effects on scalar phantom field models, providing new insights into singularity avoidance in semiclassical gravity.

Findings

Quantum corrections can influence the fate of the universe with phantom energy.

Comparison with fluid models shows similarities and differences in singularity behavior.

Results suggest possible scenarios where the Big Rip may be avoided due to quantum effects.

Abstract

Quantum corrections coming from massless fields conformally coupled with gravity are studied, in order to see if they can lead to avoidance of the annoying Big Rip singularity which shows up in a flat Friedmann-Robertson-Walker universe filled with dark energy and modeled by a scalar phantom field. The dynamics of the model are discussed for all values of the two parameters, named $\alpha>0$ and $\beta<0$, corresponding to the regularization process. The new results are compared with the ones obtained in \cite{hae11} previously, where dark energy was modeled by means of a phantom fluid with equation of state $P=\omega\rho$, with $\omega<-1$.