Deformations of gauged SO(8) supergravity and supergravity in eleven dimensions

TL;DR

This paper investigates the eleven-dimensional origins of the continuous family of gauged SO(8) supergravities, discussing key issues like duality frames and gauge fields, and presents a new non-linear flux ansatz for 7D supergravity.

Contribution

It provides new insights into the embedding of SO(8) supergravity in 11D and introduces a non-linear flux ansatz applicable to S^7 and T^7 truncations.

Findings

Partial resolution of duality frame issues

New non-linear flux ansatz for 7D supergravity

Discussion of obstructions in embedding continuous degeneracy

Abstract

Motivated by the fact that there exists a continuous one-parameter family of gauged SO(8) supergravities, possible eleven-dimensional origins of this phenomenon are explored. Taking the original proof of the consistency of the truncation of 11D supergravity to SO(8) gauged supergravity as a starting point, a number of critical issues is discussed, such as the preferred electric-magnetic duality frame in four dimensions and the existence of dual magnetic gauge fields and related quantities in eleven dimensions. Some of those issues are resolved but others seem to point to obstructions in embedding the continuous degeneracy in 11D supergravity. While the final outcome of these efforts remains as yet inconclusive, several new results are obtained. Among those is the full non-linear ansatz for the seven-dimensional flux expressed in terms of the scalars and pseudoscalars of 4D supergravity, valid for both the S^7 and the T^7 truncations without resorting to tensor-scalar duality.