2009/09/30 by Sean February, Julien Larena, Mathew Smith +1 · 1 citation
Physics and Astronomy · #Cosmology and Gravitation Theories #Galaxies: Formation, Evolution, Phenomena #Gamma-ray bursts and supernovae #astro-ph.CO
paper · pdf · doi:10.1111/j.1365-2966.2010.16627.x
published as Mon.Not.Roy.Astron.Soc.405:2231,2010 · 12 pages, 14 figures, typos corrected, matches the version published in MNRAS. DOI added
openalex publication_date 2010/05/11 · arxiv created 2010/05/21 · arxiv updated 2012/12/10 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/01
Dark energy observations may be explained within general relativity using an inhomogeneous Hubble-scale depression in the matter density and accompanying curvature, which evolves naturally out of an Einstein–de Sitter (EdS) model. We present a simple parametrization of a void which can reproduce concordance model distances to arbitrary accuracy, but can parametrize away from this to give a smooth density profile everywhere. We show how the Hubble constant is not just a nuisance parameter in inhomogeneous models because it affects the shape of the distance–redshift relation. Independent Hubble-rate data from age estimates can, in principle, serve to break the degeneracy between concordance and void models, but the data are not yet able to achieve this. Using the latest Constitution supernova data set, we show that robust limits can be placed on the size of a void which is roughly independent of its shape. However, the sharpness of the profile at the origin cannot be well constrained due to supernova being dominated by peculiar velocities in the local universe. We illustrate our results using some recently proposed diagnostics for the Friedmann models.