Inflation from Wrapped Branes

TL;DR

This paper explores how higher-dimensional wrapped branes can extend the inflaton field range in brane inflation models, leading to distinctive observational signatures like non-Gaussianity and gravitational waves.

Contribution

It introduces a new inflationary model using 5-branes wrapping a 2-cycle in a warped throat, highlighting the importance of backreaction effects.

Findings

Model can match CMB data in the DBI regime

Predicts strong non-Gaussian signals

Potentially detectable gravitational waves

Abstract

We show that the use of higher dimensional wrapped branes can significantly extend the inflaton field range compared to brane inflation models which use D3-branes. We construct a simple inflationary model in terms of 5-branes wrapping a 2-cycle and traveling towards the tip of the Klebanov-Strassler throat. Inflation ends when the branes reach the tip of the cone and self-annihilate. Assuming a quadratic potential for the brane it is possible to match the CMB data in the DBI regime, but we argue that the backreaction of the brane is important and cannot be neglected. This scenario predicts a strong non-Gaussian signal and possibly detectable gravitational waves.