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arXiv · 0905.4773

Time Variable Cosmological Constants from the Age of Universe

Lixin Xu·Jianbo Lu·Wenbo Li
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Abstract

In this paper, time variable cosmological constant, dubbed {\it age cosmological constant}, is investigated motivated by the fact: any cosmological length scale and time scale can introduce a cosmological constant or vacuum energy density into Einstein's theory. The age cosmological constant takes the form $ρ_Λ=3c^2M^2_P/t_Λ^2$, where $t_Λ$ is the age of our universe or conformal time. The effective equation of state of age cosmological constant are $w^{eff}_Λ=-1+{2/3}\frac{\sqrt{Ω_Λ}}{c}$ and $w^{eff}_Λ=-1+{2/3}\frac{\sqrt{Ω_Λ}}{c}(1+z)$ when the age of universe and conformal time are taken as the role of cosmological time scales respectively. They are the same as the so-called agegraphic dark energy models. However, the evolution history are different from the agegraphic ones for their different evolution equations.

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Lixin Xu, Jianbo Lu, Wenbo Li. 2009-05-29. Time Variable Cosmological Constants from the Age of Universe. https://doi.org/10.1016/j.physletb.2010.05.058

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