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arXiv · 1810.08911

Higher-order modified Starobinsky inflation

R. R. Cuzinatto·L. G. Medeiros·P. J. Pompeia
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Abstract

An extension of the Starobinsky model is proposed. Besides the usual Starobinsky Lagrangian, a term proportional to the derivative of the scalar curvature, $\nabla_μR\nabla^μR$, is considered. The analyzis is done in the Einstein frame with the introduction of a scalar field and a vector field. We show that inflation is attainable in our model, allowing for a graceful exit. We also build the cosmological perturbations and obtain the leading-order curvature power spectrum, scalar and tensor tilts and tensor-to-scalar ratio. The tensor and curvature power spectrums are compared to the most recent observations from BICEP2/Keck collaboration. We verify that the scalar-to-tensor rate $r$ can be expected to be up to three times the values predicted by Starobinsky model.

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R. R. Cuzinatto, L. G. Medeiros, P. J. Pompeia. 2019-01-31. Higher-order modified Starobinsky inflation. https://doi.org/10.1088/1475-7516%2F2019%2F02%2F055

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