On the Breakdown of Perturbation Theory

Abstract

The production of o(1/g^2) particles in a weakly-coupled theory is believed to be non-perturbatively suppressed. I comment on the prospects of (a) establishing this rigorously, and (b) estimating the effect to exponential accuracy semiclassically, by discussing two closely-related problems: the large-order behaviour of few-point Green functions, and induced excitation in quantum mechanics. Induced tunneling in the latter case is exponentially enhanced for frequencies of the order of the barrier height.

(13 pages), CPTH/C209-1292 (Talk at the Kiev Conference on: Modern Problems in QFT, Strings and Quantum Gravity, June 1992)

Cited by in corpus (5)

• Multiplicities from black-hole formation in heavy-ion collisions
• Revisiting Soliton Contributions to Perturbative Amplitudes
• The Forced Soliton Equation and Semiclassical Soliton Form Factors
• Accelerating Solitons
• Summing up the perturbation series in the Schwinger Model