  It is shown that quarks and leptons can couple intrinsically to pure
supergravity, preserving for this context the degeneracy of globally
supersymmetric vacua, and specifically preserving the vacuum that is
characterized by SU(4)XU(1). A fundamental representation of SUSY SU(4)XU(1) is
constructed in terms of quarks, and it is demonstrated that the symmetry of
this fundamental representation is invariant under supergravity interactions
that produce quark-lepton transitions. The importance of this tensorial flavor
structure is that it predicts a new, seventh quark of charge -1/3, a
left-handed (non-strange) version of the strange quark.

High Energy Physics - Phenomenology