The transient acceleration from time-dependent interacting dark energy models

TL;DR

This paper explores models where dark matter and dark energy interact in a time-dependent manner, leading to a temporary phase of cosmic acceleration that is not eternal, with analytical solutions derived for different interaction forms.

Contribution

It introduces and analyzes two phenomenological interaction models between dark matter and dark energy that can produce transient cosmic acceleration, providing analytical solutions and parameter ranges.

Findings

Transient acceleration is achievable with specific interaction parameters.

Analytical expressions for cosmic evolution are derived.

Parameter ranges for transient acceleration are identified.

Abstract

The transient acceleration which the current cosmic acceleration is not eternal is possible by introducing the interaction between dark matter and dark energy. If the energy transfer is from dark energy to dark matter, then it is possible to realize the transient acceleration. We study the possibility of transient acceleration by considering two time-dependent phenomenological interaction forms so that the energy transfer increases as the universe evolves. Starting from a simple and extending to a more complicated ansatz, we obtain analytical expressions for the evolutions of the deceleration and the various energy density parameters. We find the ranges of the parameters in the models for a transient acceleration.