A study of warm inflation model inspired by some inhomogeneous dark energy fluids

Abstract

Since the viscous effect plays an essential role in explaining the initial evolution of the present universe, therefore this paper is devoted to discussing an early cosmic phenomenon, i.e., warm inflation inspired by some interesting inhomogeneous dark energy (DE) fluid models. The viscosity in these models is determined by the nonlinear terms of the fluid’s energy density $(\sigma )$ and the Hubble parameter (H), being treated as effective corrections to a perfect DE fluid. The early acceleration is carried through inhomogeneous DE fluid coupled with radiation which paved the way to the radiation dominated epoch after inflation. In this scenario, we develop a general inflationary formalism including slow-roll parameters, e-folding numbers, scalar spectral index with its running and tensor-to-scalar ratio for this fluid representation. For considered inhomogeneous fluid models, we evaluate exact inflationary solutions during strong dissipative regime and checked the compatibility of the models as compared to recent Planck data.