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arXiv · hep-ph/9508336

Modifications of the Hubble Law in a Scale-Dependent Cosmology

Abstract

We study some observational consequences of a recently proposed scale--dependent cosmological model for an inhomogeneous Universe. In this model the Universe is pictured as being inside a highly dense and rapidly expanding shell with the underdense center. For nearby objects ($z \ll 1$), the linear Hubble diagram is shown to remain valid even in this model, which has been demonstrated both analytically and numerically. For large $z$, we present some numerical results of the redshift--luminosity distance relation and the behavior of the mass density as a function of the redshift. It is shown that the Hubble diagram in this model for a locally $open$ Universe ($Ω(t_0, r \sim 0)=0.1$) resembles that of the $flat$ Friedmann cosmology. This implies that study of the Hubble diagram cannot uniquely determine the value of $q_0$ or $Ω_0$ in a model--independent way. The model also accounts for the fact that $Ω_0$ is an increasing function of the redshift.

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BibTeXRIS

C. W. Kim, T. H. Lee, J. Song. 1995-08-21. Modifications of the Hubble Law in a Scale-Dependent Cosmology. https://doi.org/10.1142/s0217751x96002534

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