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arXiv · 0905.4052

A generalized equation of state for dark energy

E. M. Barboza Jr·J. S. Alcaniz·Zong-Hong Zhu·R. Silva
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Abstract

A generalized parameterization $w_β(z)$ for the dark energy equation of state (EoS) is proposed and some of its cosmological consequences are investigated. We show that in the limit of the characteristic dimensionless parameter $β\to +1, 0$ and -1 some well-known EoS parameterizations are fully recovered whereas for other values of $β$ the proposed parameterization admits a wider and new range of cosmological solutions. We also discuss possible constraints on the $w_β(z)$ parameters from current observational data.

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E. M. Barboza Jr, J. S. Alcaniz, Zong-Hong Zhu, R. Silva. 2009-07-24. A generalized equation of state for dark energy. https://doi.org/10.1103/physrevd.80.043521

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