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Towards inflation and dark energy cosmologies from modified Gauss-Bonnet theory

Ishwaree P Neupane·Benedict M N Carter
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Abstract

We consider a physically viable cosmological model that has a field dependent Gauss-Bonnet coupling in its effective action, in addition to a standard scalar field potential. The presence of such terms in the four dimensional effective action gives rise to several novel effects, such as a four dimensional flat Friedmann-Robertson-Walker universe undergoing a cosmic inflation at early epoch, as well as a cosmic acceleration at late times. The model predicts, during inflation, spectra of both density perturbations and gravitational waves that may fall well within the experimental bounds. Furthermore, this model provides a mechanism for reheating of the early universe, which is similar to a model with some friction terms added to the equation of motion of the scalar field, which can imitate energy transfer from the scalar field to matter

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Ishwaree P Neupane, Benedict M N Carter. 2006-05-24. Towards inflation and dark energy cosmologies from modified Gauss-Bonnet theory. https://doi.org/10.1088/1475-7516%2F2006%2F06%2F004

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