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

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 which triple interacting fluids will cross the phantom divide.