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arXiv · 2101.08538

No-go theorem for inflation in an extended Ricci-inverse gravity model

Tuan Q. Do
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Abstract

In this paper, we propose an extension of the Ricci-inverse gravity, which has been proposed recently as a very novel type of fourth-order gravity, by introducing a second order term of the so-called anticurvature scalar as a correction. The main purpose of this paper is that we would like to see whether the extended Ricci-inverse gravity model admits the homogeneous and isotropic Friedmann-Lemaitre-Robertson-Walker metric as its stable inflationary solution. However, a no-go theorem for inflation in this extended Ricci-inverse gravity is shown to appear through a stability analysis based on the dynamical system method. As a result, this no-go theorem implies that it is impossible to have such stable inflation in this extended Ricci-inverse gravity model.

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Tuan Q. Do. 2021-01-21. No-go theorem for inflation in an extended Ricci-inverse gravity model. https://doi.org/10.1140/epjc%2Fs10052-021-09974-0

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