N=4 Superconformal Symmetry for the Covariant Quantum Superstring

TL;DR

This paper extends the covariant quantum superstring formulation to N=4 superconformal symmetry, introducing new BRST charges and a framework for defining the physical spectrum within a topological model context.

Contribution

It introduces an N=4 superconformal extension of the covariant superstring with new BRST charges and a method for spectrum definition using gauged cosets.

Findings

Constructed N=4 superconformal symmetry for the superstring.

Defined new BRST charges Q_S, Q_V, and Q_C with specific anticommutation relations.

Provided a framework for identifying the physical spectrum in this extended model.

Abstract

We extend our formulation of the covariant quantum superstring as a WZNW model with N=2 superconformal symmetry to N=4. The two anticommuting BRST charges in the N=4 multiplet of charges are the usual BRST charge Q_S and a charge Q_V proposed by Dijkgraaf, Verlinde and Verlinde for topological models. Using our recent work on "gauging cosets", we then construct a further charge Q_C which anticommutes with Q_S + Q_V and which is intended for the definition of the physical spectrum.