Scenario of inflationary cosmology from the phenomenological $\Lambda$ models

Abstract

Choosing the three phenomenological models of the dynamical cosmological term $\Lambda$, viz., $\Lambda \sim (\dot{a}/a{)}^2$, $\Lambda \sim \ddot{a}/a$ and $\Lambda \sim \rho$ where $a$ is the cosmic scale factor, it has been shown by the method of numerical analysis that the three models are equivalent for the flat Universe $k=0$. The evolution plots for dynamical cosmological term $\Lambda$ vs. time $t$ and also the cosmic scale factor $a$ vs. $t$ are drawn here for $k=0,+1$. A qualitative analysis has been made from the plots which supports the idea of inflation and hence expanding Universe.

12 latex pages with 12 figures; Replaced with the revised version; Accepeted for `J. Non-lin. Frac. Phen. Sci. Engg.'