Duality-symmetric eleven-dimensional supergravity and its coupling to M-branes

The standard eleven-dimensional supergravity action depends on a three-form gauge field and does not allow direct coupling to five-branes. Using previously developed methods, we construct a covariant eleven-dimensional supergravity action depending on a three-form and six-form gauge field in a duality-symmetric manner. This action is coupled to both the M-theory two-brane and five-brane, and corresponding equations of motion are obtained. Consistent coupling relates D = 11 duality properties with self-duality properties of the M5-brane. From this duality-symmetric formulation, one derives an action describing coupling of the M-branes to standard D = 11 supergravity. © 1998 Elsevier Science B.V.