Non-perturbative processes at high energies in weakly coupled theories: Multi-instantons set an early limit

We study the role of multi-instanton configurations in the multiparticle production at high energies in the standard model. A critical point s∞ is found where one, two, three, etc. instanton-anti-instanton pairs give comparable contributions to the total cross section. For energies above this point the instanton approximation collapses. If is found that at the critical point the total cross section is still exponentially small. (orig.)