Static and Dynamic Components of the Redshift

Abstract

We analyse the possibility that the observed cosmological redshift may be cumulatively due to the expansion of the universe and the tired light phenomenon. Since the source of both the redshifts is the same, they both independently relate to the same proper distance of the light source. Using this approach we have developed a hybrid model combining the Einstein de Sitter model and the tired light model that yields a slightly better fit to Supernovae Ia redshift data using one parameter than the standard ΛCDM model with two parameters. We have shown that the ratio of tired light component to the Einstein de Sitter component of redshift has evolved from 2.5 in the past, corresponding to redshift 1000, to its present value of 1.5. The hybrid model yields Hubble constant H 0 =69.11(±0.53)km·s -1 ·Mpc -1 and the deceleration parameter q 0 =-0.4. The component of Hubble constant responsible for expansion of the universe is 40% of H 0 and for the tired light is 60% of H 0 . Consequently, the critical density is only 16% of its currently accepted value; a lot less dark matter is needed to make up the critical density. In addition, the best data fit yields the cosmological constant density parameter =0. The tired light effect may thus be considered equivalent to the cosmological constant in the hybrid model.