Radiation and Matter in an Open Cosmological Model

Abstract

THE discovery1 of the cosmic background radiation has stimulated research on the cosmological model with both matter and radiation2. As usually used the Friedmann solutions correspond either to pressureless matter alone or to radiation alone Here a(τ) is a scale factor of the line element and Am, Ar are constants. These equations describe an open model with negative curvature. It seems reasonable to consider an open model because of a number of observational and theoretical arguments3. Here I consider some properties of the analytical solution for the open cosmological model containing both radiation and matter.