skip to main content

Title: Cosmic expansion histories in massive bigravity with symmetric matter coupling

We study the cosmic expansion history of massive bigravity with a viable matter coupling which treats both metrics on equal footing. We derive the Friedmann equation for the effective metric through which matter couples to the two metrics, and study its solutions. For certain parameter choices, the background cosmology is identical to that of ΛCDM. More general parameters yield dynamical dark energy, which can still be in agreement with observations of the expansion history. We study specific parameter choices of interest, including minimal models, maximally-symmetric models, and a candidate partially-massless theory.
Authors:
;  [1] ;  [2] ;  [3]
  1. Oskar Klein Center, Stockholm University, Albanova University Center, 106 91 Stockholm (Sweden)
  2. DAMTP, Centre for Mathematical Sciences, University of Cambridge, Wilberforce Rd., Cambridge CB3 0WA (United Kingdom)
  3. Institute of Theoretical Astrophysics, University of Oslo, P.O. Box 1029 Blindern, N-0315 Oslo (Norway)
Publication Date:
OSTI Identifier:
22382044
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2015; Journal Issue: 01; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; COSMOLOGY; COUPLING; EQUATIONS; EXPANSION; METRICS; NONLUMINOUS MATTER; SYMMETRY