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Scalar Field as Dark Matter and Machian Cosmological Solution in the Generalized Scalar-Tensor Theory of Gravitation

A. Miyazaki
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Abstract

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 $-\infty $.

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A. Miyazaki. 2001-03-05. Scalar Field as Dark Matter and Machian Cosmological Solution in the Generalized Scalar-Tensor Theory of Gravitation. https://arxiv.org/abs/gr-qc/0103013

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