Combining cosmological and local bounds on bimetric theory
Abstract
Ghostfree bimetric theory describes two nonlinearly interacting spin2 fields, one massive and one massless, thus extending general relativity. We confront bimetric theory with observations of Supernovae type 1a, Baryon Acoustic Oscillations and the Cosmic Microwave Background in a statistical analysis, utilising the recently proposed physical parametrisation. This directly constrains the physical parameters of the theory, such as the mass of the spin2 field and its coupling to matter. We find that all models under consideration are in agreement with the data. Next, we compare these results to bounds from local tests of gravity. Our analysis reveals that all two and three parameter models are observationally consistent with both cosmological and local tests of gravity. The minimal bimetric model (only β_{1}) is ruled out by our combined analysis.
 Publication:

Journal of Cosmology and Astroparticle Physics
 Pub Date:
 September 2021
 DOI:
 10.1088/14757516/2021/09/035
 arXiv:
 arXiv:2101.08791
 Bibcode:
 2021JCAP...09..035C
 Keywords:

 baryon acoustic oscillations;
 dark energy theory;
 modified gravity;
 supernova type Ia  standard candles;
 General Relativity and Quantum Cosmology;
 Astrophysics  Cosmology and Nongalactic Astrophysics;
 High Energy Physics  Theory
 EPrint:
 doi:10.1088/14757516/2021/09/035