Noncritical Superstrings in a Ramond-Ramond Background

TL;DR

This paper computes tachyon scattering amplitudes in noncritical Type 0A superstring theory with RR flux, revealing a polynomial dependence on flux and proposing a dual weakly-coupled theory with a massless RR scalar.

Contribution

It introduces a matrix model approach to analyze noncritical superstrings with RR flux and proposes a novel duality relating strong and weak coupling regimes.

Findings

Amplitudes become polynomial in RR flux after renormalization.

A dual superstring theory with a massless RR scalar is proposed.

The duality exchanges inverse string coupling and 0-brane charge.

Abstract

We use the recently found matrix description of noncritical superstring theory of Type 0A to compute tachyon scattering amplitudes in a background with a RR flux. We find that after the string coupling is multiplicatively renormalized, the amplitudes in any genus become polynomial in the RR flux. We propose that in the limit where both the string coupling and the RR flux go to infinity, the theory has a weakly-coupled description in terms of another superstring theory with a vanishingly small RR flux. This duality exchanges the inverse string coupling and the 0-brane charge. The dual superstring theory must have a peculiar property that its only field-theoretic degree of freedom is a massless RR scalar.