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arXiv · 0705.4147

Effect of Dynamical Cosmological Constant in presence of Modified Chaplygin Gas for Accelerating Universe

Writambhara Chakraborty·Ujjal Debnath
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Abstract

In this paper we have considered the Universe to be filled with Modified Gas and the Cosmological Constant $Λ$ to be time-dependent with or without the Gravitational Constant $G$ to be time-dependent. We have considered various phenomenological models for $Λ$, viz., $Λ\proptoρ, Λ\propto\frac{\dot{a}^{2}}{a^{2}}$ and $Λ\propto\frac{\ddot{a}}{a}$. Using these models it is possible to show the accelerated expansion of the Universe at the present epoch. Also we have shown the natures of $G$ and $Λ$ over the total age of the Universe. Using the statefinder parameters we have shown the diagramamtical representation of the evolution of the Universe starting from radiation era to $Λ$CDM model.

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Writambhara Chakraborty, Ujjal Debnath. 2007-05-29. Effect of Dynamical Cosmological Constant in presence of Modified Chaplygin Gas for Accelerating Universe. https://doi.org/10.1007/s10509-007-9710-6

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