http://arxiv.org/abs/2112.10922
Inflationary cosmology proposes that the early Universe undergoes accelerated expansion, driven, in simple scenarios, by a single scalar field, or inflaton. The form of the inflaton potential determines the initial spectra of density perturbations and gravitational waves. We show that constraints on the duration of inflation together with the BICEP3/Keck bounds on the gravitational wave background imply that higher derivatives of the potential are nontrivial with a confidence of 99%. Such terms contribute to the scale-dependence, or running, of the density perturbation spectrum. We clarify the “equivalence classes” of inflationary models in this limit, showing that models with a very small gravitational wave background typically have a larger running and that if this background is not observed by pending experiments the running could be at the threshold of detectability. Correlated expectations for the running and gravitational wave background provide an new avenue by which future observations may yield insight into possible inflationary mechanisms.
R. Easther, B. Bahr-Kalus and D. Parkinson
Wed, 22 Dec 21
1/67
Comments: 5 pages; 5 figures
You must be logged in to post a comment.