Wrapped branes and supersymmetry Original Research Article

Configurations of two or more branes wrapping different homology cycles of space-time are considered and the amount of supersymmetry preserved is analysed, generalising the analysis of multiple branes in flat space. For K3 compactifications, these give the Type II or M-theory origin of certain supersymmetric four-dimensional heterotic string solutions that fit into spin-32 multiplets and which become massless at certain points in moduli space. The interpretation of these BPS states and the possibility of supersymmetry enhancement are discussed.