Superembedding Approach and S-Duality. A unified description of superstring and super-D1-brane

TL;DR

This paper demonstrates that a superembedding equation provides a universal, S-duality invariant framework for describing superstring and super-D1-brane, unifying their superfield equations and transformations.

Contribution

It introduces a superembedding approach that unifies superstring and super-D1-brane descriptions, highlighting S-duality invariance and deriving their superfield equations of motion.

Findings

Superembedding equation yields S-duality invariant description.

Superfield equations relate superstring and super-D1-brane.

Potential universal description for other IIB branes via 6D superembedding.

Abstract

It is proved that a basic superembedding equation for the 2-dimensional worldsheet superspace $\S^{(2|8+8)}$ embedded into D=10 type IIB superspace $M^{(10|16+16)}$ provides a universal, S-duality invariant description of a fundamental superstring and super-D1-brane. We work out generalized action principle, obtain superfield equations of motion for both these objects and find how the S-duality transformations relate the superfield equations of superstring and super-D1-brane. The superembedding of 6-dimensional worldsheet superspace $\S^{(6|16)}$ into the D=10 type IIB superspace will probably provide a similar universal description for the set of type IIB super-NS5-brane, super-D5-brane and a Kaluza-Klein monopole (super-KK5-brane).