Inflationary Models Driven by Adiabatic Matter Creation

TL;DR

This paper analyzes inflationary cosmological models driven by matter creation, showing how different parameters influence universe evolution and identifying a de Sitter solution as a universal attractor.

Contribution

It generalizes previous matter creation inflation models and examines their dynamical properties, highlighting the role of a key parameter in universe evolution.

Findings

Universes can emerge as Big-Bang or Minkowski depending on parameter .

De Sitter solution acts as a universal attractor for expanding models.

Curvature effects do not prevent inflationary attractor behavior.

Abstract

The flat inflationary dust universe with matter creation proposed by Prigogine and coworkers is generalized and its dynamical properties are reexamined. It is shown that the starting point of these models depends critically on a dimensionless parameter $\Sigma$, closely related to the matter creation rate $\psi$. For $\Sigma$ bigger or smaller than unity flat universes can emerge, respectively, either like a Big-Bang FRW singularity or as a Minkowski space-time at $t=-\infty$. The case $\Sigma=1$ corresponds to a de Sitter-type solution, a fixed point in the phase diagram of the system, supported by the matter creation process. The curvature effects have also been investigated. The inflating de Sitter is a universal attractor for all expanding solutions regardless of the initial conditions as well as of the curvature parameter.