A New Sigma Model Action for the Four-Dimensional Green-Schwarz Heterotic Superstring

TL;DR

This paper introduces a novel sigma model action for the four-dimensional Green-Schwarz heterotic superstring that incorporates new features like an N=(2,0) super-worldsheet, unconstrained background fields, and a dilaton coupling, with potential generalization to ten dimensions.

Contribution

The paper presents a new sigma model action with four distinctive features for the 4D Green-Schwarz heterotic superstring, and proposes its extension to 10D.

Findings

Action constructed on N=(2,0) super-worldsheet using Kahler potential.

Target-space background fields are unconstrained.

Dilaton couples to 2D curvature.

Abstract

The sigma model action described in this paper differs in four important features from the usual sigma model action for the four-dimensional Green-Schwarz heterotic superstring in a massless background. Firstly, the action is constructed on an N=(2,0) super-worldsheet using a Kahler potential and an Ogievetsky-Sokatchev constraint; secondly, the target-space background fields are unconstrained; thirdly, the target-space dilaton couples to the two-dimensional curvature; and fourthly, the action reduces in a flat background to a free-field action. A conjecture is made for generalizing this N=(2,0) sigma model action to the ten-dimensional Green-Schwarz heterotic superstring in a manner that preserves these four new features.