1999/09/30 by Arbab I. Arbab
Physics and Astronomy · #gr-qc
published as Spacetime & Substance 1(6) (2001) 39 · A revised version
arxiv created 1999/10/21 · arxiv updated 2009/11/30
We have studied a cosmological model with a cosmological term of the form Λ=3α\fr R2R2+\bt\fr RR+\fr3γR2 α, \bt γ are constants. The scale factor (R) is found to vary linearly with time for both radiation and matter dominated epochs. The cosmological constant is found to decrease as t-2 and the rate of particle creation is smaller than the Steady State value. The model gives ΩΛ=\fr13 and Ωm=\fr23 in the present era, ΩΛ=Ωm=\fr12 in the radiation era. The present age of the universe (\rm tp) is found to be \rm tp=Hp-1 , where \rm Hp is the Hubble constant. The model is free from the main problems of the Standard Model. Since the scale factor \rm R∝ t during the entire evolution of the universe the ratio of the cosmological constant at the Planck and present time is \rm\frΛPlΛp=10120. This decay law justifies why, today, the cosmological constant is exceedingly small.