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arXiv · 1303.4353

New Constraints On The Dark Energy Equation of State

Najla Said·Carlo Baccigalupi·Matteo Martinelli·Alessandro Melchiorri·Alessandra Silvestri
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Abstract

We combine recent measurements of Cosmic Microwave Background Anisotropies, Supernovae luminosity distances and Baryonic Acoustic Oscillations to derive constraints on the dark energy equation of state w in the redshift range 0<z<2, using a principal components approach. We find no significant deviations from the expectations of a cosmological constant. However, combining the datasets we find slight indication for w<-1 at low redshift, thus highlighting how these datasets prefer a non-constant w. Nevertheless the cosmological constant is still in agreement with these observations, while we find that some classes of alternative models may be in tension with the inferred w(z) behaviour.

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Najla Said, Carlo Baccigalupi, Matteo Martinelli, Alessandro Melchiorri, Alessandra Silvestri. 2013-03-18. New Constraints On The Dark Energy Equation of State. https://doi.org/10.1103/physrevd.88.043515

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