A parabolic matter-radiation model of the universe

A study of matter-radiation universes under certain supplementary conditions specified in the introduction shows us that the only model of this class compatible with observations is a parabolic universe which at the present time is almost the same as an Einstein-de Sitter model. The numerical values obtained for Hubble's constant, the age of the universe and the matter density at the present time are quite acceptable. We can also obtain some limits for the mass of neutrinos. The advantage of this parabolic model is that it gives the same results as thet^2/3 model at the present time and what is more could be used in studying problems of the formation of galaxies, after the recombination epoch, where matter and radiation have comparable importance.