Probing beyond-Horndeski gravity on ultra-large scales
Loading...
Date
2020
Journal Title
Journal ISSN
Volume Title
Publisher
IOP Publishing Ltd
Abstract
The beyond-Horndeski gravity has recently been reformulated in the dark energy
paradigm — which has been dubbed, Unified Dark Energy (UDE). The evolution equations
for the given UDE appear to correspond to a non-conservative dark energy scenario, in which
the total energy-momentum tensor is not conserved. We investigate both the background
cosmology and, the large-scale imprint of the UDE by probing the angular power spectrum
of galaxy number counts, on ultra-large scales; taking care to include the full relativistic corrections in the observed overdensity. The background evolution shows that only an effective
mass smaller than the Planck mass is needed in the early universe in order for predictions
in the given theory to match current observational constraints. We found that the effective
mass-evolution-rate parameter, which drives the evolution of the UDE, acts to enhance the
observed power spectrum and, hence, relativistic effects (on ultra-large scales) by enlarging
the UDE sound horizon.
Description
Keywords
Dark energy theory, Galaxy clustering, Modified gravity, Power spectrum, Horndeski gravity
Citation
Duniya, D. G.A. et al. (2020). Probing beyond-Horndeski gravity on ultra-large scales. Journal of Cosmology and Astroparticle Physics, 2020(01)