Scale-free power spectrums in the delayed cosmology

TL;DR

This paper explores a delayed cosmology model where the evolution of geometries is postponed relative to matter, enabling inflation without inflaton fields, and produces a nearly scale-free primordial power spectrum from a radiation-dominated early universe.

Contribution

It introduces a novel delayed cosmology framework that achieves inflation and scale-free perturbations without traditional inflaton fields or vacuum energy.

Findings

Primordial perturbations can be nearly scale-free in this model.

The model produces inflationary behavior without inflaton fields.

A radiation-dominated early universe is compatible with the results.

Abstract

The delayed cosmology [JCAP 02(2012)046] assumes that the evolution of geometries is delayed relative to that of matter and/or energies. This idea allows inflation occur without inflaton fields or vacuum energies of any kind as drivings. We considered the production and evolution of primordial perturbations in this model. The results indicate that, with delaying, we could get a nearly scale-free power spectrum of perturbations starting from a radiation dominated early universe.