Strings in Ramond-Ramond Backgrounds from the Neveu-Schwarz-Ramond Formalism

TL;DR

This paper develops a framework using the NSR formalism to analyze RR flux backgrounds in type II string theory, computing string state corrections in specific backgrounds and confirming consistency with known limits.

Contribution

It introduces a method to compute string state corrections in RR backgrounds within the NSR formalism, including new results for pp-wave and $AdS_3\times S^3\times M_4$ backgrounds.

Findings

Correctly reproduces lightcone quantization results in the pp-wave background.

Numerically computes mass corrections for pulsating strings in $AdS_3\times S^3\times M_4$.

Results match known semiclassical and BMN limits.

Abstract

We treat RR flux backgrounds of type II string theory in the framework of closed superstring field theory based on the NSR formalism, focusing on two examples: (1) the pp-wave background supported by 5-form flux, and (2) $AdS_3\times S^3\times M_4$ supported by mixed 3-form fluxes. In both cases, we analyze the classical string field solution perturbatively, and compute the correction to the dispersion relation of string states to quadratic order in the RR flux. In the first example, our result is in a delicate way consistent with that obtained from lightcone quantization of the Green-Schwarz string. In the second example, we will obtain numerically the mass corrections to pulsating type IIB strings in $AdS_3\times S^3\times M_4$. Our results, valid at finite $AdS$ radius, agree with previously known answers in the semiclassical limit and in the BMN limit respectively.