Phantom Energy with Variable G and Λ

Arbab, Arbab I.
April 2009
AIP Conference Proceedings;4/17/2009, Vol. 1115 Issue 1, p230
Academic Journal
We have investigated a cosmological model of a phantom energy with a variable cosmo-logical constant (Λ) depending on the energy density (ρ) as Λ∝ρ-α, α = const. and a variable gravitational constant (G). The model requires α<0 and a negative gravitational constant. The cosmological constant evolves with time as, Λ∝t-2. For ω>-1 and α<-1 the cosmological constant, Λ<0, G>0 and ρ decrease with cosmic expansion. For ordinary matter (or dark matter), i.e., ω>-1 we have -1<α<0 and β>0 so that G>0 increases with time and ρ decreases with time. Cosmic acceleration with dust particles is granted provided -23<α<0 and Λ>0.


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