On inflationary parameters in scalar–tensor theories
albert munyeshyakaInternational Journal of Geometric Methods in Modern Physics
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Abstract
The equivalence between [Formula: see text] and scalar–tensor theories is revisited, we consequently explored different [Formula: see text] models. After consideration of specific definition of the scalar field, we derived the potentials [Formula: see text] for each [Formula: see text] model focusing on the early Universe, mostly the inflation epoch. For a given potential, we applied the slow-roll approximation approach to each [Formula: see text] model and obtained the expressions for the spectral index [Formula: see text] and tensor-to-scalar ratio [Formula: see text]. We determined the corresponding numerical values associated with each of the [Formula: see text] models. Our results showed that for certain choice of parameter space, the values of [Formula: see text] and [Formula: see text] are consistent with the Planck survey results and others produce numerical values that are in the same range as suggested by Planck data. We further constructed the Klein–Gordon equations (KGEs...
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