The Dynamic Cosmological Term $\Lambda$: Some Aspects of Phenomenological Models

Abstract

Choosing a phenomenological model of $\Lambda$, viz. $\Lambda \sim \dot{H}$, it has been shown that this model of $\Lambda$ is equivalent to other three types of $\Lambda$, $\Lambda \sim (\dot{a}/a{)}^2$, $\Lambda \sim \ddot{a}/a$ and $\Lambda \sim \rho$. Through an indirect approach, it has also been possible to put a limit on the deceleration parameter $q$. It has been shown that if $q$ becomes less than -1, then this model can predict about the presence of phantom energy.

Latex, 9 pages