Type IIA Supergravity Excitations in Plane-Wave Background

TL;DR

This paper analyzes the spectrum of low-lying excitations in Type IIA superstring theory within a plane wave background, providing explicit calculations and establishing a correspondence with string states.

Contribution

It explicitly computes the supergravity fluctuation spectrum in a solvable plane wave background and links it to the string state spectrum in light-cone gauge.

Findings

Explicit supergravity fluctuation spectrum obtained

Spectrum matches zero-mode sector of superstring Hamiltonian

Superstring action is exactly solvable in this background

Abstract

We study the low-lying excitations of Type IIA superstring theory in a plane wave background with 24 supersymmetries. In the light-cone gauge, the superstring action has ${\cal N}=(4,4)$ supersymmetry and is exactly solvable, since it is quadratic in superstring coordinates. We obtain explicitly the spectrum of the Type IIA supergravity fluctuation modes in the plane wave background and give its correspondence with the spectrum of string states from the zero-mode sector of the light-cone superstring Hamiltonian.