Scalar Field as Dark Matter and Machian Cosmological Solution in the Generalized Scalar-Tensor Theory of Gravitation
نویسنده
چکیده
The Machian cosmological solution satisfying φ = O(ρ/ω) in the generalized scalar-tensor theory of gravitation with the varying cosmological constant is summarized. The scalar field φ with the exponential potential is introduced as dark matter and the barotropic evolution of matter in the universe is discussed. As the universe expands, the coefficient γ of the equation of state approaches to −1/3 and the coupling function ω(φ) diverges to −∞. PACS numbers: 04.50.+h, 98.80.-k ∗Email: [email protected], [email protected]
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Machian Cosmological Solution in the Generalized Scalar-Tensor Theory of Gravitation
The Machian cosmological solution satisfying φ = O(ρ/ω) is discussed for the homogeneous and isotropic universe with a perfect fluid (with negative pressure) in the generalized scalar-tensor theory of gravitation. We propose ω(φ) = η/(ξ − 2) for the coupling function in the Machian point of view. The parameter ξ varies in time very slowly from ξ = 0 to ξ = 2 because of the physical evolution of...
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