On the resolution of cosmic coincidence problem and phantom crossing with triple interacting fluids

TL;DR

This paper explores a cosmological model with three interacting fluids to address the triple coincidence problem and conditions for crossing the phantom divide, providing insights into the energy dynamics of the universe.

Contribution

It introduces a novel model with triple fluid interactions and derives conditions for phantom crossing, advancing understanding of cosmic energy density coincidences.

Findings

Conditions for triple fluids to cross the phantom divide are established.

The model offers a potential explanation for the near-equality of cosmic energy densities.

Interactions among three fluids influence the evolution of the universe's energy composition.

Abstract

We here investigate a cosmological model in which three fluids interact with each other involving certain coupling parameters and energy exchange rates. The motivation of the problem stems from the puzzling `triple coincidence problem' which naively asks why the cosmic energy densities of matter, radiation and dark energy are almost of the same order of magnitude at the present time. In our model, we determine the conditions under triple interacting fluids will cross the phantom divide.