  We present a new parton model approach for hadron-hadron interactions and, in
particular, for the initial stage of nuclear collisions at very high energies
(RHIC, LHC and beyond). The most important aspect of our approach is a
self-consistent treatment, using the same formalism for calculating cross
sections and particle production, based on an effective, QCD-inspired field
theory, where many of the inconsistencies of presently used models will be
avoided.
  In addition, we provide a unified treatment of soft and hard scattering, such
that there is no fundamental cutoff parameter any more defining an artificial
border between soft and hard scattering.
  Our approach cures some of the main deficiencies of two of the standard
procedures currently used: the Gribov-Regge theory and the eikonalized parton
model. There, cross section calculations and particle production cannot be
treated in a consistent way using a common formalism. In particular, energy
conservation is taken care of in case of particle production, but not
concerning cross section calculations. In addition, hard contributions depend
crucially on some cutoff, being divergent for the cutoff being zero. Finally,
in case of several elementary scatterings, they are not treated on the same
level: the first collision is always treated differently than the subsequent
ones. All these problems are solved in our new approach.
