Quantum-gravitational effects on gauge-invariant scalar and tensor perturbations during inflation: The de Sitter case

TL;DR

This paper calculates quantum-gravitational corrections to inflationary perturbations using a semiclassical approach, revealing an enhancement of power on large scales in a de Sitter universe.

Contribution

It introduces a semiclassical Born-Oppenheimer method to derive quantum-gravitational corrections to inflationary power spectra in a de Sitter background.

Findings

Quantum-gravitational corrections enhance large-scale power.

Corrections derived from a semiclassical approximation.

Results specific to the de Sitter inflationary model.

Abstract

We present detailed calculations for quantum-gravitational corrections to the power spectra of gauge-invariant scalar and tensor perturbations during inflation. This is done by performing a semiclassical Born-Oppenheimer type of approximation to the Wheeler-DeWitt equation, from which we obtain a Schroedinger equation with quantum-gravitational correction terms. As a first step, we perform our calculation for a de Sitter universe and find that the correction terms lead to an enhancement of power on the largest scales.