Inflationary epoch in the presence of holographic dark energy

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, which makes it relevant only for modes that crossed the horizon during the first e-folds of inflation. For the primordial gravitational waves we find the spectral index receives a correction from the graviton mass term, and it can be blue-tilted, depending on the mass of the tensor mode.