The effect of thermal radiation on singularities in the dark universe

TL;DR

This paper investigates how thermal radiation effects influence the development and classification of singularities in a cosmological model with viscous dark fluid and dark matter, revealing potential transitions between singularity types.

Contribution

It introduces the impact of Hawking radiation on singularity evolution in inhomogeneous viscous dark fluid cosmology, showing possible transitions between singularity types.

Findings

Thermal effects can induce a transition from type I to type III singularities.

Inclusion of thermal effects may prevent the formation of singularities.

Viscous dark fluid dynamics significantly alter singularity outcomes.

Abstract

Cosmological models with an inhomogeneous viscous dark fluid, coupled with dark matter in the Friedmann- Robertson-Walker (FRW) flat universe, are considered. The influence of thermal effects caused by Hawking radiation on the visible horizon is studied, in connection with the classified type I and type III singularities which are known to occur within a finite amount of time. Allowance of thermal effects implies that a transition to a type II singularity can take place, in a finite time. We take into account a bulk viscosity of the dark fluid, observing the equation of state in the case of radiation, and find that there is a qualitative change in the singular universe of type I: it may pass into a singularity of type III, or it may avoid the singularity at all.