The consistency condition for the three-point function in dissipative single-clock inflation

TL;DR

This paper extends the inflationary consistency condition for the three-point function to dissipative, multi-field models, providing a proof within an effective field theory framework and highlighting conditions for its validity.

Contribution

It generalizes the inflationary consistency condition to dissipative multi-field models using an effective field theory approach, with explicit proof to leading order.

Findings

Consistency condition holds under certain conditions with many degrees of freedom

Departures from the condition could rule out broad classes of inflation models

Provides a theoretical framework for future experimental tests

Abstract

We generalize the consistency condition for the three-point function in single field inflation to the case of dissipative, multi-field, single-clock models. We use the recently introduced extension of the effective field theory of inflation that accounts for dissipative effects, to provide an explicit proof to leading (non-trivial) order in the generalized slow roll parameters and mixing with gravity scales. Our results illustrate the conditions necessary for the validity of the consistency relation in situations with many degrees of freedom relevant during inflation, namely that there is a preferred clock. Departures from this condition in forthcoming experiments would rule out not only single field but also a large class of multi-field models.