Quantum cosmological consistency condition for inflation

TL;DR

This paper explores how quantum cosmology can predict the initial conditions and energy scale of inflation through a tunneling probability distribution, linking quantum origins to observable CMB polarization signatures.

Contribution

It introduces a path-integral approach to derive a tunneling probability distribution that predicts inflation's initial conditions and energy scale, providing a testable quantum cosmological consistency condition.

Findings

A sharp peak in the tunneling probability distribution indicates the most probable initial inflationary state.

The method is explicitly demonstrated for natural inflation, showing its applicability.

The approach connects quantum cosmological predictions with observable CMB B-polarization signatures.

Abstract

We investigate the quantum cosmological tunneling scenario for inflationary models. Within a path-integral approach, we derive the corresponding tunneling probability distribution. A sharp peak in this distribution can be interpreted as the initial condition for inflation and therefore as a quantum cosmological prediction for its energy scale. This energy scale is also a genuine prediction of any inflationary model by itself, as the primordial gravitons generated during inflation leave their imprint in the B-polarization of the cosmic microwave background. In this way, one can derive a consistency condition for inflationary models that guarantees compatibility with a tunneling origin and can lead to a testable quantum cosmological prediction. The general method is demonstrated explicitly for the model of natural inflation.