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arXiv · 1103.0257

Probing the time dependence of dark energy

E. M. Barboza Jr.·J. S. Alcaniz
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Abstract

A new method to investigate a possible time-dependence of the dark energy equation of state $w$ is proposed. We apply this methodology to two of the most recent data sets of type Ia supernova (Union2 and SDSS) and the baryon acoustic oscillation peak at $z = 0.35$. For some combinations of these data, we show that there is a clear departure from the standard $Λ$CDM model at intermediary redshifts, although a non-evolving dark energy component ($dw/dz = 0$) cannot be ruled out by these data. The approach developed here may be useful to probe a possible evolving dark energy component when applied to upcoming observational data.

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E. M. Barboza Jr., J. S. Alcaniz. 2011-03-01. Probing the time dependence of dark energy. https://doi.org/10.1088/1475-7516%2F2012%2F02%2F042

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