How to Produce an Arbitrarily Small Tensor to Scalar Ratio

Abstract

We construct a toy a model which demonstrates that large field single scalar inflation can produce an arbitrarily small scalar to tensor ratio in the window of e-foldings recoverable from CMB experiments. This is done by generalizing the $\alpha$-attractor models to allow the potential to approach a constant as rapidly as we desire for super-planckian field values. This implies that a non-detection of r alone can never rule out entirely the theory of large field inflation.