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arXiv · 2211.05212

Alternative approach to the Starobinsky model for inflation scenarios

Masud Chaichian·Amir Ghal'e·Markku Oksanen
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Abstract

The $R+R^2$ model of gravity with the corresponding shallow potential in the Einstein frame is consistent with the observations. Recently, many efforts have been made to generalize the $R+R^2$ (Starobinsky) model of inflation or use other shallow potentials to construct a model for the early Universe. We revise the question about the shallow potential. We propose a model in which the Starobinsky model can emerge through a dynamical mechanism. We show that the absence of ghost modes results to constraints on the parameters of the Starobinsky model. We obtain the scalar spectral index and the tensor-to-scalar ratio of the extended model and study the three-point correlation function of the curvature perturbation to estimate the primordial non-Gaussianities of the proposed model.

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Masud Chaichian, Amir Ghal'e, Markku Oksanen. 2022-10-27. Alternative approach to the Starobinsky model for inflation scenarios. https://doi.org/10.1103/physrevd.107.023527

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