The Doubled Geometry of Nilmanifold Reductions

TL;DR

This paper develops a doubled geometric framework for nilmanifold reductions in string theory, unifying various dualities such as T-folds, exotic branes, and R-flux within a single geometric setting.

Contribution

It introduces a novel doubled geometry approach that captures multiple dual descriptions of nilmanifold spaces in string theory.

Findings

Unified description of dual spaces as slices of a doubled space

Connection of nilmanifolds to T-folds and exotic branes

Framework for understanding R-flux and other dualities

Abstract

A class of special holonomy spaces arise as nilmanifolds fibred over a line interval and are dual to intersecting brane solutions of string theory. Further dualities relate these to T-folds, exotic branes, essentially doubled spaces and spaces with R-flux. We develop the doubled geometry of these spaces, with the various duals arising as different slices of the doubled space.