Lorentz Boosts as Squeeze Transformations and the Parton Picture
  It was shown by Gribov, Ioffe, Pomeranchuk in 1966 and by Ioffe in 1969 that a space-time picture is needed for the Lorentz deformation of hadronic interaction region. It is shown that this deformation is a squeeze transformation. It is shown also that Feynman's parton picture emerges as a consequence of Lorentz-squeezed hadrons in the quark model. 
Y. S. Kim