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 light-like
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 regular horizon which have one quarter of unbroken
supersymmetry. The centrino multiplet includes a massive spin 3/2 state, the
centrino, as a highest spin state.
Existence of massive black hole supermultiplets may affect the massless
sector of the theory. Assuming that 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 centrino may
provide a consistent super-Higgs mechanism.
Preprint
Comment: 15 pages, LaTeX
Subjects: High Energy Physics - Theory; Astrophysics; General Relativity and Quantum Cosmology; High Energy Physics - Phenomenology