摘要
The dilaton in Weyl-Scale induced gravitational theory is regarded as a candidate of dark energy. When the potential of dilaton field is taken as the form Wσ ＋ σ^2e^-βσ2, that there exist attractor solutions to the canonical dilatonic dark energy model and the phontam model, and these attractors correspond to an equation of state ω = -1 and a cosmic density parameter Ωσ = 1, which are important features for a dark energy model and can fit with the current observations. We find a sufficient condition of the existence of a late time de Sitter attractor. The attractor behaviors, the evolutions of the state parameter ω and the cosmic density parameter Ω, the evolution of X （σ/σ0） and Y （σ/σ0^2） with respect to N（ln a）are shown numerically.
The dilaton in Weyl-Scale induced gravitational theory is regarded as a candidate of dark energy.When the potential of dilaton field is taken as the form Wσ + σ2e-βσ2, that there exist attractor solutions to the canonical dilatonic dark energy model and the phontam model, and these attractors correspond to an equation of state ω =-1 and a cosmic density parameter Ωσ = 1, which are important features for a dark energy model and can it with the current observations.We find a suffcient condition of the existence of a late time de Sitter attractor.The attractor behaviors, the evolutions of the state parameter ω and the cosmic density parameter Ω, the evolution of X( σ/σ0)and Y(σσ/02)with respect to N(ln a) are shown numerically.
基金
supported by the National Natural Science Foundation of China (Grant Nos.10573012, 10575068)
the Science Foundation of Shanghai Municipal Commission of Science and Technology (Grant No.04dz05905)
