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The Behaviour Of Cosmological Models With Varying-G

John D. Barrow·Paul Parsons
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Abstract

We provide a detailed analysis of Friedmann-Robertson-Walker universes in a wide range of scalar-tensor theories of gravity. We apply solution-generating methods to three parametrised classes of scalar-tensor theory which lead naturally to general relativity in the weak-field limit. We restrict the parameters which specify these theories by the requirements imposed by the weak-field tests of gravitation theories in the solar system and by the requirement that viable cosmological solutions be obtained. We construct a range of exact solutions for open, closed, and flat isotropic universes containing matter with equation of state $p\leq \frac{1}{3}ρ$ and in vacuum. We study the range of early and late-time behaviours displayed, examine when there is a `bounce' at early times, and expansion maxima in closed models.

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John D. Barrow, Paul Parsons. 1996-07-29. The Behaviour Of Cosmological Models With Varying-G. https://doi.org/10.1103/physrevd.55.1906

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