Hadron interactions in the U-70 energy range: results and problems

From late 1967 until the early 1970s, the Soviet proton synchrotron (better known as the Serpukhov accelerator or U-70), with a nominal laboratory energy of up to 76 GeV, was the world leader. During these few years, several results of fundamental significance were obtained (partially in collaboration with physicists from CERN, France, and other countries). Let us briefly outline the main provisions of the paradigm that reigned at that time in the field of strong interaction theory.