Electron-positron annihilation: unitarity, scaling and electrodynamics at high energies

The work on e+e- annihilation by Cabibbo, Wolfenstein and the author is reviewed. The restrictions of unitarity are analyzed and the connection between the cross sections sigmasub(h) (into hadrons) and sigmasub(μ) (into muons) is derived. The possibility of non-scaling in e+e- annihilation is studied and it is pointed out that it leads to no contradiction with presently available information. It is further pointed out that non-scaling could provide a cut-off mechanism for quantum electrodynamics. (author)