Maximally supersymmetric solutions of ten- and eleven-dimensional supergravities
José Figueroa-O'Farrill, George Papadopoulos
TL;DR
The paper delivers a complete local classification of maximally supersymmetric backgrounds in eleven- and ten-dimensional supergravity, showing that all such vacua arise from either AdS×S geometries, flat space, or Hpp-waves. The authors derive this by enforcing the vanishing of the supercovariant curvature $\\mathcal{R}_{MN}$, decomposing $F$ via gamma-matrix expansions, and proving that the four-form $F$ must be parallel and decomposable; this leads to a dichotomy between Freund–Rubin product geometries and Cahen–Wallach plane waves. The results yield explicit locally isometric backgrounds: in M-theory the AdS$_7\times$S$^4$, AdS$_4\times$S$^7$ vacua with corresponding $F$-flux, the flat vacuum, and the maximally supersymmetric Hpp-wave; in IIB the AdS$_5\times$S$^5$ and the maximally supersymmetric Hpp-wave; and in the remaining theories only flat space vacua or none in the massive IIA case. These findings have implications for AdS/CFT and the role of plane-wave limits in string theory, providing a geometric and algebraic framework for understanding all maximal SUSY backgrounds across ten and eleven dimensions.
Abstract
We classify (up to local isometry) the maximally supersymmetric solutions of the eleven- and ten-dimensional supergravity theories. We find that the AdS solutions, the Hpp-waves and the flat space solutions exhaust them.
