Will there be again a transition from acceleration to deceleration in course of the dark energy evolution of the universe?

TL;DR

This paper investigates the evolution of dark energy and dark matter interactions in the universe, analyzing conditions for transitions between acceleration and deceleration phases through autonomous system analysis.

Contribution

It introduces a model of interacting dark fluids with non-gravitational coupling and derives conditions for multiple transitions in the universe's acceleration behavior.

Findings

Multiple zeros of the deceleration parameter are possible.

Conditions for transition from acceleration to deceleration are identified.

Examples demonstrate scenarios with vanishing deceleration parameter.

Abstract

In this work we consider the evolution of the interactive dark fluids in the background of homogeneous and isotropic FRW model of the universe. The dark fluids consist of a warm dark matter and a dark energy and both are described as perfect fluid with barotropic equation of state. The dark species interact non-gravitationally through an additional term in the energy conservation equations. An autonomous system is formed in the energy density spaces and fixed points are analyzed. A general expression for the deceleration parameter has been obtained and it is possible to have more than one zero of the deceleration parameter. Finally, vanishing of the deceleration parameter has been examined with some examples.