We show that only by performing generalized dimensional reductions all possible brane configurations are taken into account and one gets the complete lowerdimensional theory. We apply this idea to the reduction of type IIB supergravity in an SL(2, R)-covariant way and establish T duality for the type II superstring effective action in the context of generalized dimensional reduction giving the corresponding generalized Buscher's T duality rules.The full (generalized) dimensional reduction involves all the S duals of D-7-branes: Q-7-branes and a sort of composite 7-branes. The three species constitute an SL(2, Z) triplet. Their presence induces the appearance of the triplet of masses of the 9dimensional theory.The T duals, including a "KK-8A-brane", which must have a compact transverse dimension have to be considered in the type IIA side. Compactification of 11dimensional KK-9M-branes (a.k.a. M-9-branes) on the compact transverse dimension give D-8-branes while compactification on a worldvolume dimension gives KK-8Abranes. The presence of these KK-monopole-type objects breaks translation invariance and two of them given rise to an SL(2, R)-covariant massive 11-dimensional supergravity whose reduction gives the massive 9-dimensional type II theories.

Abstract. We describe the construction of a Lie superalgebra associated to an arbitrary supersymmetric M-theory background, and discuss some examples. We prove that for backgrounds with more than 24 supercharges, the bosonic subalgebra acts locally transitively. In particular, we prove that backgrounds with more than 24 supersymmetries are necessarily (locally) homogeneous.

We classify all the supersymmetric configurations of ungauged N = 2, d = 4 supergravity coupled to n vector multiplets and determine under which conditions they are also classical solutions of the equations of motion. The supersymmetric configurations fall into two classes, depending on the timelike or null nature of the Killing vector constructed from Killing spinor bilinears. The timelike class configurations are essentially the ones found by Behrndt, Lüst and Sabra, which exhaust this class and are the ones that include supersymmetric black holes. The null class configurations include pp-waves and cosmic strings.

We extend the topological Kerr-Newman-aDS solutions by including NUT charge and find generalizations of the Robinson-Bertotti solution to the negative cosmological constant case with different topologies. We show how all these solutions can be obtained as limits of the general Plebanski-Demianski solution.We study the supersymmetry properties of all these solutions in the context of gauged N = 2, d = 4 supergravity. Generically they preserve at most 1/4 of the total supersymmetry. In the Plebanski-Demianski case, although gauged N = 2, d = 4 supergravity does not have electric-magnetic duality, we find that the family of supersymmetric solutions still enjoys a sort of electric-magnetic duality in which electric and magnetic charges and mass and Taub-NUT charge are rotated simultaneously.

We classify the supersymmetric solutions of ungauged N = 1 d = 5 SUGRA coupled to vector multiplets and hypermultiplets. All the solutions can be seen as deformations of solutions with frozen hyperscalars. We show explicitly how the 5-dimensional Reissner-Nordström black hole is deformed when hyperscalars are living on SO(4, 1)/SO(4) are turned on, reducing its supersymmetry from 1/2 to 1/8. We also describe in the timelike and null cases the solutions that have one extra isometry and can be reduced to N = 2, d = 4 solutions. Our formulae allows the uplifting of certain N = 2, d = 4 black holes to N = 1, d = 5 black holes on KK monopoles or to pp-waves propagating along black strings.