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Imprints of the Metrically-coupled Dilaton on Density Perturbations in Inflationary Cosmology

Takeshi Chiba·Naoshi Sugiyama·Jun'ichi Yokoyama
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Abstract

Spectra of density perturbations produced during chaotic inflation are calculated, taking both adiabatic and isocurvature modes into account in a class of scalar-tensor theories of gravity in which the dilaton is metrically coupled. Comparing the predicted spectrum of the cosmic microwave background radiation anisotropies with the one observed by the COBE-DMR we calculate constraints on the parameters of these theories, which turn out to be stronger by an order-of-magnitude than those obtained from post-Newtonian experiments.

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Takeshi Chiba, Naoshi Sugiyama, Jun'ichi Yokoyama. 1998-05-27. Imprints of the Metrically-coupled Dilaton on Density Perturbations in Inflationary Cosmology. https://doi.org/10.1016/s0550-3213(98)00412-x

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