BransDicke Gravity with a Cosmological Constant Smoothes Out ΛCDM Tensions
Abstract
We analyze BransDicke gravity with a cosmological constant, Λ, and cold dark matter (BDΛCDM) in the light of the latest cosmological observations on distant supernovae, Hubble rate measurements at different redshifts, baryonic acoustic oscillations, largescale structure formation data, gravitational weaklensing, and the cosmic microwave background under full Planck 2015 cosmic microwave background likelihood. Our analysis includes both the background and perturbations equations. We find that BDΛCDM is observationally favored as compared to the concordance ΛCDM model, which is traditionally defined within General Relativity (GR). In particular, some wellknown persisting tensions of the ΛCDM with the data, such as the excess in the mass fluctuation amplitude {σ }_{8} and especially the acute H _{0}tension with the local measurements, essentially disappear in this context. Furthermore, viewed from the GR standpoint, BDΛCDM cosmology mimics quintessence at ≳ 3σ c.l. near our time.
 Publication:

The Astrophysical Journal
 Pub Date:
 November 2019
 DOI:
 10.3847/20418213/ab53e9
 arXiv:
 arXiv:1909.02554
 Bibcode:
 2019ApJ...886L...6S
 Keywords:

 Cosmology;
 Cosmological models;
 Cosmological parameters;
 Relativistic cosmology;
 Cosmological evolution;
 Largescale structure of the universe;
 Dark matter;
 Astrophysics  Cosmology and Nongalactic Astrophysics;
 General Relativity and Quantum Cosmology;
 High Energy Physics  Phenomenology
 EPrint:
 The present version, accepted for publication in Astrophys.J. Lett., contains an extended analysis (Fig. 1 is more complete) and also new comments. References added