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arXiv · 1911.04482

Inflation driven by a holographic energy density

A. Oliveros·Mario A. Acero
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Abstract

In this letter we study a model of inflation in which the inflationary regimen comes from a type of holographic energy density. In particular, we consider the Granda-Oliveros proposal for the holographic energy density, which contains two free dimensionless parameters, $\alpha$ and $\beta$. This holographic energy density is associated to the so-called Granda-Oliveros infrared cutoff (G-O cutoff). Additionally, since in the inflationary regimen the energy scales are very high, it is necessary to modify the G-O cutoff taking into account a correction due to the ultraviolet cutoff. In this way, we obtain an algebraic equation which implicitly includes the Hubble parameter (as a function of e-folding number, $N$) and from this, we calculate the Hubble slow-roll parameters and the values of the inflationary observables: the scalar spectral index of the curvature perturbations and its running, the tensor spectral index and the tensor-to-scalar ratio. Finally, since the values for these inflationary observables are known (Planck 2018 observations), we present constraints on the parameters $\alpha$ and $\beta$ to make this a viable model.

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A. Oliveros, Mario A. Acero. 2019-11-11. Inflation driven by a holographic energy density. https://doi.org/10.1209/0295-5075%2F128%2F59001

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