BLACK-HOLE MULTIPLETS AND SPONTANEOUS BREAKING OF LOCAL SUPERSYMMETRY

We classify states saturating a double or a single supersymmetric positivity bound of a four-dimensional N = 4 supersymmetry. The massive four-dimensional double-bound states (Bogomolny states) are shown to form a lightlike representation of ten-dimensional supersymmetry. The single-bound states form a massive representation (centrino multiplet) of a four-dimensional supersymmetry. The first component of the centrino multiplet is identified with extreme black holes with a regular horizon which have one-quarter of the unbroken supersymmetry. The centrino multiplet includes a massive spin-3/2 state, the centrino, as the highest spin state. The existence of massive black hole supermultiplets may affect the massless sector of the theory. Assuming that a gluino condensate is formed one can study its properties. The bilinear combination of covariantly constant Killing spinors supplies the possible form for a gluino condensate. The condensate has null properties, does not introduce a cosmological constant, and may lead to a spontaneous breaking of local supersymmetry. This suggests that the centrino may provide a consistent super-Higgs mechanism.