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arXiv · 0908.3186

No Evidence for Dark Energy Dynamics from a Global Analysis of Cosmological Data

Paolo Serra·Asantha Cooray·Daniel E. Holz·Alessandro Melchiorri·Stefania Pandolfi·Devdeep Sarkar
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Abstract

We use a variant of principal component analysis to investigate the possible temporal evolution of the dark energy equation of state, w(z). We constrain w(z) in multiple redshift bins, utilizing the most recent data from Type Ia supernovae, the cosmic microwave background, baryon acoustic oscillations, the integrated Sachs-Wolfe effect, galaxy clustering, and weak lensing data. Unlike other recent analyses, we find no significant evidence for evolving dark energy; the data remains completely consistent with a cosmological constant. We also study the extent to which the time-evolution of the equation of state would be constrained by a combination of current- and future-generation surveys, such as Planck and the Joint Dark Energy Mission.

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Paolo Serra, Asantha Cooray, Daniel E. Holz, Alessandro Melchiorri, Stefania Pandolfi, Devdeep Sarkar. 2009-08-21. No Evidence for Dark Energy Dynamics from a Global Analysis of Cosmological Data. https://doi.org/10.1103/physrevd.80.121302

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