Inflationary epoch in the presence of holographic dark energy

TL;DR

This paper investigates how holographic dark energy influences inflationary dynamics, affecting scalar and tensor perturbations, with potential observable consequences in the early universe's inflationary phase.

Contribution

It introduces a model incorporating holographic dark energy into single-field slow-roll inflation and analyzes its effects on power spectra and spectral indices.

Findings

Scalar power spectrum includes a correction proportional to holographic energy density.

Gravitational wave spectral index is affected by a decaying graviton mass term.

Corrections are significant at the start of inflation and diminish rapidly.

Abstract

We analyze the effects of the holographic dark energy model in a single field slow-roll inflation, taking into account both the holographic and the dark radiation components. In particular, we obtain the background evolution and compute the scalar and tensor power spectra. For the scalar sector we show that the power spectrum of the curvature perturbation encompasses the standard single field result and a correction proportional to $\Omega_{\rm hde}/\epsilon$, where $\Omega_{\rm hde}$ is the fractional density of the holographic component and $\epsilon$ is the first slow-roll parameter. This correction might be of order unity in the very beginning of the inflationary phase and decays rapidly. For the primordial gravitational waves we find the spectral index receives a correction from the graviton mass term, which decays in the first inflationary e-folds.