Searching for Signals of Inhomogeneity Using Multiple Probes of the Cosmic Expansion Rate H(z)

2021/05/25 by S. M. Koksbang
Physics and Astronomy · #Astrophysics #COSMIC cancer database #Computer science #Cosmology and Gravitation Theories #Dark Matter and Cosmic Phenomena #Physics #Radio Astronomy Observations and Technology #astro-ph.CO

paper · pdf · doi:10.1103/physrevlett.126.231101

published as Phys. Rev. Lett. 126, 231101 (2021) · 6 pages, 2 captioned figures. Accepted for publication in PRL

arxiv created 2021/05/25 · openalex created_date 2021/06/07 · openalex publication_date 2021/06/09 · arxiv updated 2021/06/11 · openalex updated_date 2026/08/05

Abstract

It is argued that cosmic chronometers yield estimates of the spatially averaged expansion rate even in a universe that is not well described by a global FLRW model-as long as the universe is statistically homogeneous and isotropic with a sufficiently small homogeneity scale. On the other hand, measurements of the expansion rate based on observations of redshift drift will not in general yield estimates of the spatially averaged expansion rate-but it will in the case where the universe is described well by a single FLRW model on large scales. Therefore, a disagreement between measurements of the expansion rate based on cosmic chronometers versus redshift drift is an expected signal of non-negligible cosmic backreaction.

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