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arXiv · hep-th/9212033

On the Breakdown of Perturbation Theory

C. Bachas
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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.

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C. Bachas. 1992-12-04. On the Breakdown of Perturbation Theory. https://doi.org/10.1007/bf01017133

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