Non-minimal Inflationary Attractors

TL;DR

This paper explores generalized inflationary models with non-minimal coupling to gravity, demonstrating that their predictions rapidly converge to universal values as the coupling parameter varies, indicating attractor behavior.

Contribution

It introduces and analyzes a new class of inflationary models with non-minimal coupling, showing their predictions are attractors converging to universal values.

Findings

Models with non-minimal coupling exhibit attractor behavior.

Predictions for n_s and r converge to universal values as || increases.

Universal predictions align with those at conformal coupling  = -1/6.

Abstract

Recently we identified a new class of (super)conformally invariant theories which allow inflation even if the scalar potential is very steep in terms of the original conformal variables. Observational predictions of a broad class of such theories are nearly model-independent. In this paper we consider generalized versions of these models where the inflaton has a non-minimal coupling to gravity with \xi <0 different from its conformal value \xi = -1/6. We show that these models exhibit attractor behavior. With even a slight increase of |\xi| from |\xi| = 0, predictions of these models for n_s and r rapidly converge to their universal model-independent values corresponding to conformal coupling \xi = -1/6. These values of n_s and r practically coincide with the corresponding values in the limit of infinitely large negative \xi.