Exceptional generalised geometry for massive IIA and consistent reductions

TL;DR

This paper develops an exceptional generalised geometry framework for massive IIA supergravity, enabling consistent reductions and new insights into gauge groups, with a focus on the effects of the Romans mass.

Contribution

It introduces a deformation of the generalised Lie derivative for massive IIA and constructs a parallelisation on S^6 for consistent truncations, extending understanding of gauge groups in supergravity.

Findings

Constructed a deformed generalised Lie derivative for massive IIA.

Reproduced the dyonically gauged ISO(7) supergravity from S^6 parallelisation.

Provided evidence that certain reductions do not exist in the massive theory.

Abstract

We develop an exceptional generalised geometry formalism for massive type IIA supergravity. In particular, we construct a deformation of the generalised Lie derivative, which generates the type IIA gauge transformations as modified by the Romans mass. We apply this new framework to consistent Kaluza-Klein reductions preserving maximal supersymmetry. We find a generalised parallelisation of the exceptional tangent bundle on S^6, and from this reproduce the consistent truncation ansatz and embedding tensor leading to dyonically gauged ISO(7) supergravity in four dimensions. We also discuss closely related hyperboloid reductions, yielding a dyonic ISO(p,7-p) gauging. Finally, while for vanishing Romans mass we find a generalised parallelisation on S^d, d=4,3,2, leading to a maximally supersymmetric reduction with gauge group SO(d+1) (or larger), we provide evidence that an analogous reduction does not exist in the massive theory.