Consistently violating the non-Gaussian consistency relation

TL;DR

This paper demonstrates that in non-attractor inflation models, the bispectrum's squeezed limit obeys a background evolution-based relation, which can be derived through symmetry arguments without solving perturbation equations.

Contribution

It reveals that the squeezed limit of the bispectrum in non-attractor models follows a relation dictated by background evolution, challenging previous assumptions about violations.

Findings

The bispectrum's squeezed limit respects a background evolution relation.

Symmetry arguments suffice to derive the relation, avoiding complex equations.

Non-attractor models do not violate the background-based consistency relation.

Abstract

Non-attractor models of inflation are characterized by the super-horizon evolution of curvature perturbations, introducing a violation of the non-Gaussian consistency relation between the bispectrum's squeezed limit and the power spectrum's spectral index. In this work we show that the bispectrum's squeezed limit of non-attractor models continues to respect a relation dictated by the evolution of the background. We show how to derive this relation using only symmetry arguments, without ever needing to solve the equations of motion for the perturbations.