Generalized No-Scale Models and Classical Symmetries of Superstrings

摘要

A generalization of no-scale supergravity models is presented where scale transformations and axion-like classical symmetries of the superstrings in four-dimensions are explicitly realized as dilations and translations of the scalar fields in the Kahler manifold. A sufficient condition is that the (dimension one) dilaton fields can be arranged in matrices of a Jordan algebra. This determines four possible classes of irreducible manifolds which are symmetric spaces. An arbitrary number of matter (dimension one half) fields can be included in the Kahler potential in such a way to preserve the algebra of isometries. Among other manifolds, one obtains all Kahler symmetric spaces. This inclusion defines a generalization of flat potential models with zero cosmological constant and scalar-fermion degeneracy except for massive fermions along the flat directions of the scalar potential. For two classes of manifolds and a trilinear superpotential, a SU(1,1) x U(1) subgroup can be promoted to an exact symmetry of the effective Lagrangian. (ERA citation 13:031533)