Dark Matter Density from Heavy Neutrino Decays

Abstract

As we know the heavy neutrino decays is a successful model for describing dark matter and also is origin of the universe entropy. In this paper we use heavy neutrino decays to calculate time-dependent dark matter density. In that case we use observational data to fixing our solutions.

Viscous Modified Cosmic Chaplygin Gas Cosmology

“…It is also possible to study FRW cosmology of a Universe filled with CG [44]. CG equation of state (1) has been generalized to the form [24,45,46,47],…”

“…An important problem is determining nature of dark Universe. It is found that the dark matter may be consists of neutrinos [1] axions [2] or WIMPs (weak interactive massive particles) [3]. In that case there are several ways to specify the nature of the dark Universe.…”