DETERMINING MODEL-INDEPENDENT H0 AND CONSISTENCY TESTS
Loading...
Date
2020
Authors
Liao, Kai
Shafieloo, Arman
Keeley, Ryan E.
Linder, Eric V.
Journal Title
Journal ISSN
Volume Title
Publisher
arxiv
Abstract
We determine the Hubble constant H0 precisely (2.3% uncertainty) in a manner independent of
cosmological model through Gaussian process regression, using strong lensing and supernova data.
Strong gravitational lensing of a variable source can provide a time-delay distance D∆t and angular
diameter distance to the lens Dd. These absolute distances can anchor Type Ia supernovae, which
give an excellent constraint on the shape of the distance-redshift relation. Updating our previous
results to use the H0LiCOW program’s milestone dataset consisting of six lenses, four of which have
both D∆t and Dd measurements, we obtain H0 = 72.8
+1.6
−1.7
km/s/Mpc for a flat universe and H0 =
77.3
+2.2
−3.0
km/s/Mpc for a non-flat universe. We carry out several consistency checks on the data
and find no statistically significant tensions, though a noticeable redshift dependence persists in a
particular systematic manner that we investigate. Speculating on the possibility that this trend of
derived Hubble constant with lens distance is physical, we show how this can arise through modified
gravity light propagation, which would also impact the weak lensing σ8 tension
Description
Keywords
Type of access: Open Access, cosmology, сosmological parameters, distance scale, gravitational lensing, strong
Citation
Liao, K., Shafieloo, A., Keeley, R. E., & Linder, E. V. (2020). Determining Model-independent H 0 and Consistency Tests. The Astrophysical Journal, 895(2), L29. https://doi.org/10.3847/2041-8213/ab8dbb