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Dark energy with polytropic equation of state

Utpal Mukhopadhyay·Saibal Ray
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Abstract

Equation of state parameter plays a significant role for guessing the real nature of dark energy. In the present paper polytropic equation of state $p=ωρ^n$ is chosen for some of the kinematical $Λ$-models viz., $Λ\sim (\dot a/a)^2$, $Λ\sim \ddot a/a$ and $Λ\sim ρ$. Although in dust cases ($ω=0$) closed form solutions show no dependency on the polytropic index $n$, but in non-dust situations some new possibilities are opened up including phantom energy with supernegative ($ω<-1$) equation of state parameter.

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Utpal Mukhopadhyay, Saibal Ray. 2005-10-19. Dark energy with polytropic equation of state. https://doi.org/10.1142/s0217732308028533

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