Electroproduction of vector mesons off nuclei at ELFE: exact solution   for color transparency
  A multichannel evolution equation is developed for the density matrix describing a hadronic wave packet produced by a virtual photon and propagation through a nuclear matter. This approach is dual to the quark-gluon representation, incorporates the effects of coherence and formation times and gives an exact solution for color transparency problem at any photon energy. We propose a procedure of data analysis, which provides an unambiguous way of detection of a color transparency signal even at medium energies. 
J. H\"ufner and B.Z. Kopeliovich (Heidelberg)