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arXiv · 1702.06526

Impact of theoretical priors in cosmological analyses: the case of single field quintessence

Simone Peirone·Matteo Martinelli·Marco Raveri·Alessandra Silvestri
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Abstract

We investigate the impact of general conditions of theoretical stability and cosmological viability on dynamical dark energy models. As a powerful example, we study whether minimally coupled, single field Quintessence models that are safe from ghost instabilities, can source the CPL expansion history recently shown to be mildly favored by a combination of CMB (Planck) and Weak Lensing (KiDS) data. We find that in their most conservative form, the theoretical conditions impact the analysis in such a way that smooth single field Quintessence becomes significantly disfavored with respect to the standard LCDM cosmological model. This is due to the fact that these conditions cut a significant portion of the (w0;wa) parameter space for CPL, in particular eliminating the region that would be favored by weak lensing data. Within the scenario of a smooth dynamical dark energy parametrized with CPL, weak lensing data favors a region that would require multiple fields to ensure gravitational stability.

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Simone Peirone, Matteo Martinelli, Marco Raveri, Alessandra Silvestri. 2017-02-21. Impact of theoretical priors in cosmological analyses: the case of single field quintessence. https://doi.org/10.1103/physrevd.96.063524

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