Modified Holographic energy density driven inflation and some cosmological outcomes

TL;DR

This paper proposes a holographic energy density model for inflation, incorporating bulk viscosity, and finds that its predictions align with observational data, offering a novel approach to early universe cosmology.

Contribution

It introduces a modified holographic inflation model with analytical solutions and analyzes its compatibility with observational constraints, including bulk viscosity effects.

Findings

Inflationary observables are consistent with Planck data.

Bulk viscosity has minimal impact during inflation but increases over time.

The model's tensor-to-scalar ratio can explain primordial fluctuations.

Abstract

Motivated by the work of Nojiri et al. (2019) [S. Nojiri, S. D. Odintsov and E. N. Saridakis, Holographic inflation, Phys. Lett. B 797 (2019) 134829], the present study reports a model of inflation under the consideration that the inflationary regime is originated by a type of holographic energy density. The infrared cutoff has been selected based on the modified holographic model that is a particular case of Nojiri-Odintsov holographic dark energy \cite{odi1} that unifies phantom inflation with the acceleration of the universe on late-time. On getting an analytical solution for Hubble parameter we considered the presence of bulk viscosity and the effective equation of state parameter appeared to be consistent with the inflationary scenario with some constraints. It has also been observed that in the inflationary scenario the contribution of bulk viscosity is not of much significance and its influence is increasing with the evolution of the universe. Inflationary observables have been computed for the model and the slow-roll parameters have been computed. Finally, it has been observed that the trajectories in $n_s - r$ are compatible with the observational bound found by Planck. It has been concluded that the tensor to scalar ratio for this model can explain the primordial fluctuation in the early universe as well.