Interacting Viscous Dark Energy in Bianchi Type-I Universe

Abstract

A solution to the coincidence and Big Rip problems on the bases of an anisotropic space-time is proposed. To do so, we study the interaction between viscous dark energy and dark matter in the scope of the Bianchi type-I Universe. We parameterize the viscosity and the interaction between the two fluids by constants $\zeta_{0}$ and $\sigma$ respectively. A detailed investigation on the cosmological implications of this parametrization has been made. We have also performed a geometrical diagnostic by using the statefinder pairs $\{s, r\}$ and $\{q, r\}$ in order to differentiate between different dark energy models. Moreover, we fit the coupling parameter $\sigma$ as well as the Hubble's parameter $H_{0}$ of our model by minimizing the $\chi^{2}$ through the age differential method, involving a direct measurement of $H$.