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Inflation and Oscillations of Universe in 4D Dilatonic Gravity

P. P. Fiziev·D. A. Georgieva
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Abstract

We investigate the inflation of Universe in a model of four dimensional dilatonic gravity with a massive dilaton field $Φ$. The dilaton plays simultaneously the roles of an inflation field and a quintessence field. It yields a sequential {\em hyper}-inflation with a graceful exit to asymptotic de Sitter space-time, which is an attractor, and is approached as $\exp(-\sqrt{3Λ^{obs}} ct/2)$. The time duration of the inflation is reciprocal to the the mass of the dilaton: $Δt_{infl}\sim m_{{}_Φ}^{-1}$. The typical number of e-folds in the simplest model of this type is shown to be realistic without fine tuning.

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BibTeXRIS

P. P. Fiziev, D. A. Georgieva. 2003-01-16. Inflation and Oscillations of Universe in 4D Dilatonic Gravity. https://doi.org/10.1103/physrevd.67.064016

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