Warm-intermediate inflationary universe model with viscous pressure in high dissipative regime

Abstract

Warm inflation model with bulk viscous pressure in the context of "intermediate inflation" where the cosmological scale factor expands as $a(t)=a_0\exp(At^f)$, is studied. The characteristics of this model in slow-roll approximation and in high dissipative regime are presented in two cases: 1- Dissipative parameter $\Gamma$ as a function of scalar field $\phi$ and bulk viscous coefficient $\zeta$ as a function of energy density $\rho$. 2- $\Gamma$ and $\zeta$ are constant parameters. Scalar, tensor perturbations and spectral indices for this scenario are obtained. The cosmological parameters appearing in the present model are constrained by recent observational data (WMAP7).