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arXiv · 1901.06296

A simple $F({\cal R},ϕ)$ deformation of Starobinsky inflationary model

Dhimiter D. Canko·Ioannis D. Gialamas·George P. Kodaxis
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Abstract

We study a model including a real scalar field $ϕ$ non-minimally coupled to $F({\cal R})$ gravity, which is conformally equivalent to an Einstein-Hilbert theory, involving two real scalar fields. We consider three special cases of the potential of the field $ϕ$ in the $F({\cal R})$-frame: a vanishing potential, a mass term and a Higgs potential. All these lead to non-trivial two-field potentials in the Einstein-frame which in particular directions resemble the well-known Starobinsky model. We find, that all these cases can yield viable inflationary models in complete agreement with current observational data.

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Dhimiter D. Canko, Ioannis D. Gialamas, George P. Kodaxis. 2020-06-09. A simple $F({\cal R},ϕ)$ deformation of Starobinsky inflationary model. https://doi.org/10.1140/epjc%2Fs10052-020-8025-4

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