Compartmental and Coexistence in the Dark Sector of the Universe

Abstract

We revise the cosmological interaction between dark energy and dark matter. More precisely, we focus on models that support compartmentalization or co-existence in the dark sector of the universe. Within the framework of a homogeneous and isotropic, spatially flat Friedmann--Lema\^itre--Robertson--Walker geometry, we analyse the asymptotic behaviour of the physical parameters for two interacting models, where dark energy and dark matter have constant equations of state parameters, in the presence of dark radiation, when dark energy is described by a quintessence scalar field. For each model, we determine the asymptotic solutions and attempt to understand how the interaction affects the cosmological evolution and history.