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arXiv · astro-ph/0608439

Scalar-field-dominated cosmology with a transient accelerating phase

F. C. Carvalho·J. S. Alcaniz·J. A. S. Lima·R. Silva
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Abstract

A new cosmological scenario driven by a slow rolling homogeneous scalar field whose exponential potential $V(Φ)$ has a quadratic dependence on the field $Φ$ in addition to the standard linear term is discussed. The derived equation of state for the field predicts a transient accelerating phase, in which the Universe was decelerated in the past, began to accelerate at redshift $z \sim 1$, is currently accelerated, but, finally, will return to a decelerating phase in the future. This overall dynamic behavior is profoundly different from the standard $Λ$CDM evolution, and may alliviate some conflicts in reconciling the idea of a dark energy-dominated universe with observables in String/M-theory. The theoretical predictions for the present transient scalar field plus dark matter dominated stage are confronted with cosmological observations in order to test the viability of the scenario.

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BibTeXRIS

F. C. Carvalho, J. S. Alcaniz, J. A. S. Lima, R. Silva. 2006-08-21. Scalar-field-dominated cosmology with a transient accelerating phase. https://doi.org/10.1103/physrevlett.97.081301

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