On the Physical Significance of Infra-red Corrections to Inflationary Observables

TL;DR

This paper argues that large infra-red corrections in inflationary observables are only present in unobservable quantities, aligning with theoretical expectations about infra-red effects in cosmology.

Contribution

It clarifies that significant infra-red corrections do not affect directly observable inflationary quantities, resolving apparent discrepancies in theoretical calculations.

Findings

Infra-red corrections are large only in non-observable quantities

Observable inflationary power spectrum remains unaffected by large infra-red effects

Supports the view that infra-red effects do not compromise physical predictions

Abstract

Inflationary observables, like the power spectrum, computed at one- and higher-order loop level seem to be plagued by large infra-red corrections. In this short note, we point out that these large infra-red corrections appear only in quantities which are not directly observable. This is in agreement with general expectations concerning infra-red effects.