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Superinflation, quintessence, and nonsingular cosmologies

E. Gunzig·A. Saa·L. Brenig·V. Faraoni·T. M. Rocha Filho·A. Figueiredo
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Abstract

The dynamics of a universe dominated by a self-interacting nonminimally coupled scalar field are considered. The structure of the phase space and complete phase portraits are given. New dynamical behaviors include superinflation ($\dot{H}>0$), avoidance of big bang singularities through classical birth of the universe, and spontaneous entry into and exit from inflation. This model is promising for describing quintessence as a nonminimally coupled scalar field.

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E. Gunzig, A. Saa, L. Brenig, V. Faraoni, T. M. Rocha Filho, A. Figueiredo. 2000-12-20. Superinflation, quintessence, and nonsingular cosmologies. https://doi.org/10.1103/physrevd.63.067301

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