On the local variation of the Hubble constant

Io Odderskov, Steen Hannestad, Troels Haugbølle

Published 2014-07-28, updated 2015-02-11Version 2

We have carefully studied how local measurements of the Hubble constant, $H_0$, can be influenced by a variety of different parameters related to survey geometry, depth, and size, as well as observer position in space. Our study is based on N-body simulations of structure in the standard $\Lambda$CDM model and our conclusion is that the expected variance in measurements of $H_0$ is far too small to explain the current discrepancy between the low value of $H_0$ inferred from measurements of the cosmic microwave background (CMB) by the Planck collaboration and the value measured directly in the local universe by use of Type Ia supernovae. This conclusion is very robust and does not change with different assumptions about survey geometry and effective sky coverage or observer position in space.