# Phenomenology of Λ-CDM Model: A Possibility of Accelerating Universe with Positive Pressure

1 APC - THEORIE
APC - UMR 7164 - AstroParticule et Cosmologie, Center for cosmoparticle physics "Cosmion" - Center for cosmoparticle physics "Cosmion"
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.
keyword :
Document type :
Journal articles
International Journal of Theoretical Physics, Springer Verlag, 2011, 50, pp.939-951. <10.1007/s10773-010-0639-0>

http://hal.in2p3.fr/in2p3-00193780
Contributor : Simone Lantz <>
Submitted on : Tuesday, December 4, 2007 - 3:44:04 PM
Last modification on : Wednesday, July 27, 2016 - 2:48:48 PM

### Citation

S. Ray, M.Y. Khlopov, P.P. Ghosh, U. Mukhopadhyay. Phenomenology of Λ-CDM Model: A Possibility of Accelerating Universe with Positive Pressure. International Journal of Theoretical Physics, Springer Verlag, 2011, 50, pp.939-951. <10.1007/s10773-010-0639-0>. <in2p3-00193780>

### Metrics

Consultations de la notice