Generalized dark energy interactions with multiple fluids

C. van de Bruck, J. Mifsud, J. P. Mimoso, N. J. Nunes

Abstract
In the search for an explanation for the current acceleration of the Universe,
scalar fields are the most simple and useful tools to build models of dark energy. This field,
however, must in principle couple with the rest of the world and not necessarily in the same
way to different particles or fluids. We provide the most complete dynamical system analysis
to date, consisting of a canonical scalar field conformally and disformally coupled to both
dust and radiation. We perform a detailed study of the existence and stability conditions of
the systems and comment on constraints imposed on the disformal coupling from Big-Bang
Nucleosynthesis and given current limits on the variation of the fine–structure constant.

Journal of Cosmology and Astroparticle Physics
Volume 11
November 2016

DOI: 10.1088/1475-7516/2016/11/031
ADS Bibliographic code: 2016JCAP...11..031V