Breakdown of scaling in high-energy accelerator and cosmic-ray interactions

There is still argument about the extent to which the simple description of high energy nucleon-nucleon interactions first put forward by Feynman (Feynman 'scaling') is valid above about 1012 eV. Here we examine the latest data from the CERN pp experiments, which relate to equivalent laboratory energies up to approx. 4 x 1014 eV (√ s 900 GeV), and cosmic-ray phenomena at similar energies, and conclude that the evidence for a breakdown of scaling is still strong. (author)