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arXiv · 1510.02633

Several parametrization dark energy models comparison with Statefinder hierarchy

Jing-Zhao Qi·Wen-Biao Liu
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Abstract

We employ the Statefinder hierarchy and the growth rate of matter perturbations to explore the discrimination of $Λ$CDM and some parametrization dark energy models including the Chevallier-Polarski-Linder (CPL), the Jassal-Bagla-Padmanabhan (JBP), the Padé(\uppercase\expandafter{\romannumeral1}), (\uppercase\expandafter{\romannumeral2}). We find that the statefinder $S_3^{(m)}$ containing third derivatives of $a(t)$ can differentiate CPL and JBP from $Λ$CDM and Padé(\uppercase\expandafter{\romannumeral1}), (\uppercase\expandafter{\romannumeral2}). While the statefinder $S_4^{(1)}$ involving fourth order derivatives of $a(t)$ has more powerful discrimination that it can distinguish the Padé(\uppercase\expandafter{\romannumeral1}), (\uppercase\expandafter{\romannumeral2}) from $Λ$CDM. In addition, we show that the growth rate of matter perturbations does not play a significant role for discrimination of such parametrization dark energy models.

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Jing-Zhao Qi, Wen-Biao Liu. 2015-10-09. Several parametrization dark energy models comparison with Statefinder hierarchy. https://arxiv.org/abs/1510.02633

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