A SPINOR MODEL FOR QUANTUM COSMOLOGY

The question of the interpretation of Wheeler-DeWitt solutions in the context of cosmological models is addressed by implementing the Hamilt onian constraint as a spinor wave equation in minisuperspace. We offer a relative probability interpretation based on a non-closed vector cu rrent in this space and a prescription for a parametrisation of classi cal solutions in terms of classical time. Such a prescription can acco mmodate classically degenerate metrics describing manifolds with signa ture change. The relative probability density, defined in terms of a K illing vector of the DeWitt metric on minisuperspace, should permit on e to identify classical loci corresponding to geometries for a classic al manifold. This interpretation is illustrated in the context of a qu antum cosmology model for two-dimensional dilaton gravity.