paper

Nonminimally Assisted Inflation: A General Analysis

arXiv:2302.05866 · doi:10.1088/1475-7516/2023/05/050

Abstract

The effects of a scalar field, known as the "assistant field," which nonminimally couples to gravity, on single-field inflationary models are studied. The analysis provides analytical expressions for inflationary observables such as the spectral index (), the tensor-to-scalar ratio (), and the local-type nonlinearity parameter (). The presence of the assistant field leads to a lowering of and in most of the parameter space, compared to the original predictions. In some cases, may increase due to the assistant field. This revives compatibility between ruled-out single-field models and the latest observations by Planck-BICEP/Keck. The results are demonstrated using three example models: loop inflation, power-law inflation, and hybrid inflation.

v1: 27 pages; v2: 34 pages, analysis improved, references updated, accepted for publication in JCAP

References in corpus (15)

Nonminimally Assisted Inflation: A General Analysis · wovepaper