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arXiv · astro-ph/0305368

The value of the equation of state of dark energy

Raul Jimenez
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Abstract

From recent CMB and Large Scale Structure observations the value of the equation of state of dark energy, assuming it to be constant in time, is constrained to be -1.3<w<-0.7 at the 95% confidence level: consistent with dark energy being a classical vacuum term. Here we describe two novel and independent methods, sensitive to different systematics, that give the same value for w and similar confidence regions. This suggests that systematics are not an issue in current determinations of w. The first method yields a measurement of $w$ that relies on the minimum number of model-dependent parameters; the second method is a non-parametric measurement of the time dependence of w(z). We also present a method to statistically determine the edge of a distribution.

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Raul Jimenez. 2003-05-20. The value of the equation of state of dark energy. https://doi.org/10.1016/j.newar.2003.07.004

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