The Scalar-Tensor Inflationary Cosmology
نویسنده
چکیده
In this paper the scalar-tensor theory of gravity is assumed to describe the evolution of the universe and the gravitational scalar φ is ascribed to play the role of inflaton. The theory is characterized by the specified coupling function ω(φ) and the cosmological function λ(φ). The function λ(φ) is nearly constant for 0 < φ < 0.1 and λ(1) = 0. The functions λ(φ) and ω(φ) provide a double-well potential for the motion of φ(t). Inflation commences and ends naturally by the dynamics of the scalar field. The energy density of matter increases steadily during inflation. When the constant Γ in the action is determined by the present matter density, the temperature at the end of inflation is of the order of 1014GeV in no need of reheating. Furthermore, the gravitational scalar is just the cold dark matter that men seek for. PACS: 04.20.-q; 98.80.Cq.
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