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arXiv · 1005.2415

No Evidence for Dark Energy Evolution from a global analysis of cosmological data

Paolo Serra
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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. 2010-05-13. No Evidence for Dark Energy Evolution from a global analysis of cosmological data. https://arxiv.org/abs/1005.2415

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