Strong Dynamics and Natural Inflation

TL;DR

This paper explores a string theory-based model of natural inflation where axions and infladrons interact, resulting in a flattened potential suitable for large field inflation, resilient to wormhole corrections.

Contribution

It introduces a novel string compactification setup with St"uckelberg couplings and chiral fermions that enables natural-like inflation with a stabilized potential.

Findings

Realization of natural-like inflation with a closed string axion as inflaton

Scalar potential flattened by infladrons' back-reaction

Model remains stable against axionic wormhole corrections

Abstract

We continue our investigation of the 4d effective field theory for closed string axions in Type II compactifications with D-branes. The inclusion of St\"uckelberg couplings for the axions requires the presence of chiral fermions at D-brane intersections, whose interactions at strong non-Abelian gauge coupling induce mass terms for the axions and scalar chiral condensate excitations, dubbed infladrons. The set-up allows for a realization of natural-like inflation with a closed string axion as inflaton and a flattened scalar potential due to the back-reaction of the more massive infladrons. We further point out that this large field inflationary model is not compromised by axionic wormhole corrections.