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arXiv · 1609.09855

Testing coupled dark energy models with their cosmological background evolution

Carsten van de Bruck·Jurgen Mifsud·Jack Morrice
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Abstract

We consider a cosmology in which dark matter and a quintessence scalar field responsible for the acceleration of the Universe are allowed to interact. Allowing for both conformal and disformal couplings, we perform a global analysis of the constraints on our model using Hubble parameter measurements, baryon acoustic oscillation distance measurements, and a Supernovae Type Ia data set. We find that the additional disformal coupling relaxes the conformal coupling constraints. Moreover we show that, at the background level, a disformal interaction within the dark sector is preferred to both $\Lambda$CDM and uncoupled quintessence, hence favouring interacting dark energy.

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Carsten van de Bruck, Jurgen Mifsud, Jack Morrice. 2016-09-30. Testing coupled dark energy models with their cosmological background evolution. https://doi.org/10.1103/physrevd.95.043513

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