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arXiv · 2103.01182

$\beta$-function reconstruction of Palatini inflationary attractors

Alexandros Karam·Sotirios Karamitsos·Margus Saal
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Abstract

Attractor inflation is a particularly robust framework for developing inflationary models that are insensitive to the details of the potential. Such models are most often considered in the metric formulation of gravity. However, non-minimal models may not necessarily maintain their attractor nature in the Palatini formalism where the connection is independent of the metric. In this work, we employ the $\beta$-function formalism to classify the strong coupling limit of inflationary models in both the metric and the Palatini approaches. Furthermore, we determine the range of values for the non-minimal coupling that lead to theories being observationally indistinguishable in metric and Palatini within current accuracy. Finally, we reconstruct the Jordan frame potential for $\xi$-attractors by imposing an explicit form for the $\beta$-function, demonstrating the effect that the choice of metric or Palatini has on the inflationary observables of the theory.

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Alexandros Karam, Sotirios Karamitsos, Margus Saal. 2021-03-01. $\beta$-function reconstruction of Palatini inflationary attractors. https://doi.org/10.1088/1475-7516/2021/10/068

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