String Dualities and the Geroch Group

TL;DR

This paper explores the symmetries and dualities in string theory backgrounds, focusing on the effective 4D theory with axion and dilaton fields, revealing the structure of T and S dualities and their relations.

Contribution

It identifies and analyzes the T and S string duality symmetries within the effective theory, highlighting their intertwining relations and the role of the Geroch group.

Findings

Identification of O(2,2) symmetry in reduced string backgrounds

Clarification of T and S duality relations

Insight into the structure of string dualities in effective theories

Abstract

We examine the properties and symmetries of the lowest order effective theory of 4-dim string backgrounds with axion and dilaton fields and zero cosmological constant. The dimensional reduction yields an O(2,2) current group of transformations in the presence of two commuting Killing symmetries. Special emphasis is placed on the identification of the T and S string duality symmetries, and their intertwining relations. (Contributed to the Proceedings of the Satellite Colloquium "Topology, Strings and Integrable Models" to the XIth International Congress of Mathematical Physics, Paris, 25--28 July 1994; Diderot Editeur.)