The string origin of dyonic ${\cal N}=8$ supergravity and its simple Chern-Simons duals

TL;DR

This paper reveals the higher-dimensional origin of a class of dyonic ${ m N}=8$ supergravity from massive IIA supergravity, identifies its dual CFT$_3$ theories, and confirms the duality through precise free energy calculations.

Contribution

It establishes the connection between dyonic ${ m N}=8$ supergravity and massive IIA supergravity, and provides the first precise AdS$_4$/CFT$_3$ match in this context.

Findings

Supergravity arises from massive IIA on $S^6$ with Romans mass.

Critical points uplift to new AdS$_4$ vacua.

Exact free energy match between supergravity and CFT$_3$.

Abstract

We clarify the higher-dimensional origin of a class of dyonic gaugings of $D=4$ ${\cal N}=8$ supergravity recently discovered, when the gauge group is chosen to be ISO(7). This dyonically-gauged maximal supergravity arises from consistent truncation of massive IIA supergravity on $S^6$, and its magnetic coupling constant descends directly from the Romans mass. The critical points of the supergravity uplift to new AdS$_4$ massive type IIA vacua. We identify the corresponding CFT$_3$ duals as super-Chern-Simons-matter theories with simple gauge group SU$(N)$, with level $k$ given by the Romans mass. In particular, we find a critical point that uplifts to the first explicit ${\cal N}=2$ AdS$_4$ massive IIA background. We compute its free energy and that of the candidate dual Chern-Simons theory by localisation to a solvable matrix model, and find perfect agreement. This provides the first AdS$_4$/CFT$_3$ precision match in massive type IIA string theory.