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arXiv · 0709.0009

Consequences of a Cosmic Scalar with Kinetic Coupling to Curvature

Scott F. Daniel·Robert R. Caldwell
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Abstract

The classical gravitational theory of a scalar field with a gradient coupling to the Ricci tensor is examined. This is a scalar-vector-tensor gravitational theory, but in the case that the coupling is weak and the scalar evolves like a quintessence field on cosmological time scales, the field equations within the solar system are similar to a vector-tensor theory predicting tightly-constrained preferred-frame effects. In the early universe, it is shown that strong coupling effects can damp the evolution of the scalar field rolling down a potential to help drive an inflationary epoch. In the absence of a potential, the strong coupling effects drive a coasting expansion epoch which ultimately terminates in a sudden singularity.

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Scott F. Daniel, Robert R. Caldwell. 2007-08-31. Consequences of a Cosmic Scalar with Kinetic Coupling to Curvature. https://doi.org/10.1088/0264-9381%2F24%2F22%2F017

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