How to falsify scenarios with primordial fluctuations from inflation

TL;DR

The paper argues that the inflationary origin of primordial fluctuations can be definitively falsified through observational constraints, especially via future CMB measurements, challenging the notion that inflation predictions are unfalsifiable.

Contribution

It demonstrates that inflationary perturbations are strongly constrained by Gaussianity and passivity, making their falsification possible with upcoming observational data.

Findings

Inflationary perturbations are falsifiable based on their statistical properties.

Future CMB satellites can test and potentially disprove inflation as the origin of primordial fluctuations.

Inflation does not predict anything that cannot be tested and potentially falsified.

Abstract

I argue that the proposition that primordial perturbations were produced by inflation is most definitely falsifyable. Far from ``predicting anything you want'', the Gaussianity and passivity of inflationary perturbations strongly constrain the possible outcomes. For example, the next generation of CMB satellites could easily prove that the perturbations do not have an inflationary origin.