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arXiv · 2206.09000

Revisiting $f(R)$ gravity's rainbow: Inflation and primordial fluctuations

Yoelsy Leyva·Giovanni Otalora
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Abstract

We study inflation and the generation of primordial fluctuations in $f(R)$ gravity's rainbow. We calculate the cosmological perturbations and then the scalar and tensor primordial power spectrum. We contrast the predictions of the model with the current observational data from PLANCK and BICEP/Keck. Particularly, we found new results for the scalar spectral index $n_s$ and the tensor-to-scalar ratio $r$ along with new observational constraints on the rainbow functions.

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Yoelsy Leyva, Giovanni Otalora. 2022-06-17. Revisiting $f(R)$ gravity's rainbow: Inflation and primordial fluctuations. https://doi.org/10.1088/1475-7516%2F2023%2F04%2F030

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