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arXiv · 1608.07806

Viable Mimetic Completion of Unified Inflation-Dark Energy Evolution in Modified Gravity

S. Nojiri·S. D. Odintsov·V. K. Oikonomou
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Abstract

In this paper, we demonstrate that a unified description of early and late-time acceleration is possible in the context of mimetic $F(R)$ gravity. We study the inflationary era in detail and demonstrate that it can be realized even in mimetic $F(R)$ gravity where traditional $F(R)$ gravity fails to describe the inflation. By using standard methods we calculated the spectral index of primordial curvature perturbations and the scalar-to-tensor ratio. We use two $F(R)$ gravity models and as it turns out, for both the models under study the observational indices are compatible with both the latest Planck and the BICEP2/Keck array data. Finally, the graceful exit from inflation is guaranteed by the existence of growing curvature perturbations when the slow-roll era ends.

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S. Nojiri, S. D. Odintsov, V. K. Oikonomou. 2016-08-28. Viable Mimetic Completion of Unified Inflation-Dark Energy Evolution in Modified Gravity. https://doi.org/10.1103/physrevd.94.104050

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