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Pre-Inflation in the Presence of Conformal Coupling

A. Kuiroukidis·D. B. Papadopoulos
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Abstract

We consider a massless scalar field, conformally coupled to the Ricci scalar curvature, in the pre-inflation era of a closed FLRW Universe. The scalar field potential can be of the form of the Coleman-Weinberg one-loop potential, which is flat at the origin and drives the inflationary evolution. For positive values of the conformal parameter ξ, less than the critical value xi_c=(1/6), the model admits exact solutions with non-zero scale factor and zero initial Hubble parameter. Thus these solutions can be matched smoothly to the so called Pre-Big-Bang models. At the end of this pre-inflation era one can match inflationary solutions by specifying the form of the potential and the whole solution is of the class C^(1).

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A. Kuiroukidis, D. B. Papadopoulos. 2004-01-13. Pre-Inflation in the Presence of Conformal Coupling. https://doi.org/10.1142/s0217732304013386

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