"Phantom" Inflation in Warped Compactification

TL;DR

This paper explores a novel inflationary scenario driven by anti D3-branes in warped compactifications, revealing a nearly scale-invariant spectrum of perturbations through a mechanism similar to phantom inflation.

Contribution

It introduces a new inflation model where the number of anti D3-branes drives inflation, connecting string theory compactifications with observable cosmological perturbations.

Findings

Inflation can be driven by the p anti D3-branes at the throat tip.

The perturbation spectrum is nearly scale invariant.

The model aligns with phantom inflation dynamics.

Abstract

In this paper, in a class of warped compactifications with the brane/flux annihilation, we find that the inflation may be driven by a flat direction identified as that along the number p of anti D3-branes located at the tip of the Klebanov-Strassler throat. The spectrum of adiabatic perturbation generated during inflation is nearly scale invariant, which may be obtained by using the results shown in the phantom inflation, since in a four-dimension effective description the evolution of energy density along the $p$ direction is slowly increasing.