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arXiv · 0711.0686

Phenomenology of $\Lambda$-CDM model: a possibility of accelerating Universe with positive pressure

Saibal Ray·Maxim Khlopov·Utpal Mukhopadhyay·Partha Pratim Ghosh
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Abstract

Among various phenomenological $\Lambda$ models, a time-dependent model $\dot \Lambda\sim H^3$ is selected here to investigate the $\Lambda$-CDM cosmology. Using this model the expressions for the time-dependent equation of state parameter $\omega$ and other physical parameters are derived. It is shown that in $H^3$ model accelerated expansion of the Universe takes place at negative energy density, but with a positive pressure. It has also been possible to obtain the change of sign of the deceleration parameter $q$ during cosmic evolution.

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Saibal Ray, Maxim Khlopov, Utpal Mukhopadhyay, Partha Pratim Ghosh. 2007-11-05. Phenomenology of $\Lambda$-CDM model: a possibility of accelerating Universe with positive pressure. https://doi.org/10.1007/s10773-010-0639-0

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