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arXiv · 1601.07356

The Local Value of $H_0$ in an Inhomogeneous Universe

I. Odderskov·S. M. Koksbang·S. Hannestad
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Abstract

The effects of local inhomogeneities on low redshift $H_0$ determinations are studied by estimating the redshift-distance relation of mock sources in N-body simulations. The results are compared to those obtained using the standard approach based on Hubble's law. The comparison shows a clear tendency for the standard approach to yield lower values of $H_0$ than the approach based on the scheme using light rays. The difference is, however, small. More precisely, it is found that the overall effect of inhomogeneities on the determination of $H_0$ is a small increase in the local estimates of about $0.3\%$ compared to the results obtained with Hubble's law, when based on a typical distribution of supernovae in the redshift range $0.01 < z < 0.1$. The overall conclusion of the study is a verification of the results that have earlier been obtained by using Hubble's law: The effects of inhomogeneities on local $H_0$ estimates are not significant enough to make it plausible that differences in high- and low-redshift estimates of $H_0$ are due to small inhomogeneities within the setting of standard cosmology.

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I. Odderskov, S. M. Koksbang, S. Hannestad. 2016-01-28. The Local Value of $H_0$ in an Inhomogeneous Universe. https://doi.org/10.1088/1475-7516%2F2016%2F02%2F001

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