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arXiv · 1210.6375

Statefinder diagnostic of logarithmic entropy corrected holographic dark energy with Granda-Oliveros IR cut-off

Abstract

In this work, we have studied the logarithmic entropy corrected holographic dark energy (LECHDE) model with Granda-Oliveros (G-O) IR cutoff. The evolution of dark energy (DE) density $Ω'_D$, the deceleration parameter, $q$, and equation of state parameter (EoS), $ω_Λ$, are calculated. We show that the phantom divide may be crossed by choosing proper model parameters, even in absence of any interaction between dark energy and dark matter. By studying the statefinder diagnostic and $ω_Λ-ω_Λ^{\prime}$ analysis, the pair parameters $\{r,s\}$ and $(ω_Λ-ω_Λ^{\prime})$ is calculated for flat GO-LECHDE universe. At present time, the pair $\{r,s\}$ can mimic the $Λ$CDM scenario for a value of $α/β\simeq 0.87$, which is lower than the corresponding one for observational data ($α/β=1.76$) and for Ricci scale ($α/β=2$). We find that at present, by taking the various values of ($α/β$), the different points in $r-s$ and $(ω_Λ-ω_Λ^{\prime})$ plans are given. Moreover, in the limiting case for a flat dark dominated universe at infinity ($t\rightarrow \infty$), we calculate $\{r,s\}$ at G-O scale. For Ricci scale ($α= 2$, $β= 1$) we obtain $\{r=0,s=2/3\}$.

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BibTeXRIS

A. Khodam-Mohammadi, Antonio Pasqua, M. Malekjani, Iuliia Khomenko, M. Monshizadeh. 2013-03-05. Statefinder diagnostic of logarithmic entropy corrected holographic dark energy with Granda-Oliveros IR cut-off. https://doi.org/10.1007/s10509-013-1400-y

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