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On the Asymptotic Behaviour of Cosmological Models in Scalar-Tensor Theories of Gravity

Andrew Billyard·Alan A Coley·Jesus Ibanez
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Abstract

We study the qualitative properties of cosmological models in scalar-tensor theories of gravity by exploiting the formal equivalence of these theories with general relativity minimally coupled to a scalar field under a conformal transformation and field redefinition. In particular, we investigate the asymptotic behaviour of spatially homogeneous cosmological models in a class of scalar-tensor theories which are conformally equivalent to general relativistic Bianchi cosmologies with a scalar field and an exponential potential whose qualitative features have been studied previously. Particular attention is focussed on those scalar-tensor theory cosmological models, which are shown to be self-similar, that correspond to general relativistic models that play an important rôle in describing the asymptotic behaviour of more general models (e.g., those cosmological models that act as early-time and late-time attractors).

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Andrew Billyard, Alan A Coley, Jesus Ibanez. 1998-07-20. On the Asymptotic Behaviour of Cosmological Models in Scalar-Tensor Theories of Gravity. https://doi.org/10.1103/physrevd.59.023507

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