1Department of Physics, Faculty of Science, University of Khartoum, PO Box 321, Khartoum 11115, Sudan2Department of Physics and Applied athematics, Faculty of Applied Sciences and Computer, Omdurman Ahlia University, PO Box 786, Omdurman, Sudan
Viscous Dark Energy Models with Variable G and Λ
Arbab I. Arbab
1Department of Physics, Faculty of Science, University of Khartoum, PO Box 321, Khartoum 11115, Sudan2Department of Physics and Applied athematics, Faculty of Applied Sciences and Computer, Omdurman Ahlia University, PO Box 786, Omdurman, Sudan
摘要We consider a cosmological model with bulk viscosity η and variable cosmological Λ∝ρ -α, alpha= const and gravitational G constants. The model exhibits many interesting cosmological features. Inflation proceeds du to the presence of bulk viscosity and dark energy without requiring the equation of state p=-ρ. During the inflationary era the energy density ρ does not remain constant, as in the de-Sitter type. Moreover, the cosmological and gravitational constants increase exponentially with time, whereas the energy density and viscosity decrease exponentially with time. The rate of mass creation during inflation is found to be very huge suggesting that all matter in the universe is created during inflation.
Abstract：We consider a cosmological model with bulk viscosity η and variable cosmological Λ∝ρ -α, alpha= const and gravitational G constants. The model exhibits many interesting cosmological features. Inflation proceeds du to the presence of bulk viscosity and dark energy without requiring the equation of state p=-ρ. During the inflationary era the energy density ρ does not remain constant, as in the de-Sitter type. Moreover, the cosmological and gravitational constants increase exponentially with time, whereas the energy density and viscosity decrease exponentially with time. The rate of mass creation during inflation is found to be very huge suggesting that all matter in the universe is created during inflation.
(Particle-theory and field-theory models of the early Universe (including cosmic pancakes, cosmic strings, chaotic phenomena, inflationary universe, etc.))
Arbab I. Arbab. Viscous Dark Energy Models with Variable G and Λ[J]. 中国物理快报, 2008, 25(10): 3834-3836.
Arbab I. Arbab. Viscous Dark Energy Models with Variable G and Λ. Chin. Phys. Lett., 2008, 25(10): 3834-3836.
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2008, Vol. 25 
