Loop Quantum Cosmology corrections on gravity waves produced during primordial inflation

TL;DR

This paper investigates how Loop Quantum Cosmology modifies the behavior of primordial gravitational waves during inflation, potentially affecting observable features in the Cosmic Microwave Background.

Contribution

It analyzes the impact of holonomy and inverse-volume corrections from LQC on the primordial tensor power spectrum, revealing significant deviations from standard predictions.

Findings

Primordial gravity waves are affected by quantum corrections.

Tensor power spectrum can be suppressed or boosted at large scales.

Deviations from standard power-law behavior are observed.

Abstract

Loop Quantum Gravity (L.Q.G.) is one of the two most promising tentative theory for a quantum description of gravity. When applied to the entire universe, the so-called Loop Quantum Cosmology (L.Q.C.) framework offers microscopical models of the very early stages of the cosmological history, potentially solving the initial singularity problem via bouncing solutions or setting the universe in the appropriate initial conditions for inflation to start, via a phase of super-inflation. More interestingly, L.Q.C. could leave a footprint on cosmological observables such as the Cosmic Microwave Background (CMB) anisotropies. Focusing on the modified dispersion relation when holonomy and inverse-volume corrections arising from the L.Q.C. framework are considered, it is shown that primordial gravity waves generated during inflation are affected by quantum corrections. Depending on the type of corrections, the primordial tensor power spectrum is either suppressed or boosted at large length scales, and strongly departs from the power-law behavior expected in the standard scenario.