A Cosmological Model of Thermodynamic Open Universe

TL;DR

This paper generalizes Prigogine's early universe model by including radiation, showing a vacuum instability origin for the universe, and connects it to quantum particle creation, resulting in a continuous evolution to the current universe.

Contribution

It introduces a radiation-dominated cosmological model based on vacuum instability, extending Prigogine's particle creation framework with new insights into cosmic background radiation.

Findings

Universe originates from vacuum instability, not a singularity.

Model transitions from rapid early evolution to de-sitter phase.

Results align with observed cosmic background radiation.

Abstract

In this paper we have given a generalisation of the earlier work by Prigogine et al. who have constructed a phenomenological model of entropy production via particle creation in the very early universe generated out of the vacuum rather than from a singularity, by including radiation also as the energy source and tried to develop an alternative cosmological model in which particle creation prevents the big bang. We developed Radiation dominated model of the universe which shows a general tendency that (i) it originates from instability of vacuum rather than from a singularity. (ii) Up to a characteristic time cosmological quantities like density, pressure, Hubble constant and expansion parameter vary rapidly with time. (iii) After the characteristic time these quantities settles down and the models are turned into de-sitter type model with uniform matter, radiation, creation densities and Hubble's constant H. The de-sitter regime survives during a decay time then connects continuously to a usual adiabatic matter radiation RW universe.The interesting thing in the paper is that we have related the phenomenological radiation dominated model to macroscopic model of quantum particle creation in the early universe giving rise to the present observed value of cosmic background radiation . It is also found that the dust filled model tallies exactly with that of the Prigogine's one, which justifies that our model is generalized Prigogine's model. Although the model originates from instability of vacuum rather than from a singularity, still there is a couple of unavoidable singularities in the model.