Hubble speed from first principles

Physical review. D/Physical review. D., vol. 107

Abstract

We introduce a way of measuring ${H}_{0}$ from a combination of independent geometrical data sets, without the need for calibration or the choice of a cosmological model. We build on the distance duality relation, which sets the ratio of the luminosity and angular diameter distance to a fixed scaling in redshift for any metric theory of gravity with standard photon propagation and constitutes a founding block of any theory describing our Universe. Our method allows us to determine ${H}_{0}$ from first principles, unleashing the measurement of this fundamental constant from calibration and the assumption of a cosmological model. We find ${H}_{0}=69.5\ifmmode\pm\else\textpm\fi{}1.7\text{ }\text{ }\mathrm{km}/\mathrm{s}/\mathrm{Mpc}$ at 68% C.L., showing that the Hubble constant can be constrained at the percent level with minimal assumptions.

Authors 2

1. Fabrizio Renzi corresponding Aachen Lorentz Institute for Theoretical Physics

   Leiden University

   Affiliation as printed

   Lorentz Institute for Theoretical Physics, Leiden University, P.O. Box 9506, Leiden 2300 RA, Netherlands

2. Alessandra Silvestri Aachen Lorentz Institute for Theoretical Physics

   Leiden University

   Affiliation as printed

   Lorentz Institute for Theoretical Physics, Leiden University, P.O. Box 9506, Leiden 2300 RA, Netherlands