P-nflation: generating cosmic Inflation with p-forms

TL;DR

The paper investigates inflation driven by p-forms non-minimally coupled to gravity, extending scalar and vector inflation to higher forms. It constructs a general non-minimal action for a massive p-form and analyzes the 2- and 3-form cases in FRW, showing they can realize slow-roll–like backgrounds with isotropy achieved by triplets or large numbers of fields. Through duality, it derives dual vector and dual scalar theories that feature higher-derivative, curvature-dependent kinetic terms, distinguishing them from standard chaotic inflation except in special backgrounds like de Sitter. Stability analyses indicate possible ghost instabilities for the 1- and 2-forms, while the 3-form case can be ghost-free in slow-roll, though a full perturbation treatment is deferred. Overall, p-nflation broadens the space of inflationary models and may yield distinctive observational signatures in the CMB.

Abstract

We show that an inflationary background might be realized by using any p-form non-minimally coupled to gravity. Standard scalar field inflation corresponds to the 0-form case and vector inflation to the 1-form. Moreover, we show that the 2- and 3-form fields are dual to a new vector and scalar inflationary theories where the kinetic terms are non-minimally coupled to gravity.