Little Rip and Pseudo Rip cosmological models with coupled dark energy based on a new generalized entropy

Abstract

We study Little Rip (LR) and Pseudo Rip (PR) cosmological models containing two coupled fluids: dark energy and dark matter. We assume a spatially flat Friedmann-Robertson-Walker (FRW) universe. The interaction between the dark energy and the dark matter fluid components is described in terms of the parameters in the generalized equation of state (EoS) in presence of the bulk viscosity. We consider entropic cosmology and use a description based on a new generalized entropy function, which was proposed by Nojiri-Odintsov-Faraoni [1]. Conditions for the appearance of the (LR) and the (PR) in terms of the parameters of the (EoS) are obtained. Introducing an energy density ${\rho }_g$ corresponding to a specified entropy function $S_g$, together with an interaction term $Q$ in the gravitational equations of motion, we derive modified forms of the EoS parameters. We discuss the corrections of the thermodynamic parameters associated with the generalized entropy function. Properties of the late universe as well as in the early universe in this formalism are pointed out.

8 pages latex, no figures, to appear in Int. J. Geom. Meth. Mod. Phys

Cited by in corpus (2)

• A preference for dynamical phantom dark energy using one-parameter model with Planck, DESI DR1 BAO and SN data
• Cosmological Tensions with Non-Extensive Entropic Cosmology: A Modified Stress-Energy Approach