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arXiv · 1612.04376

Instantons from Perturbation Theory

Marco Serone·Gabriele Spada·Giovanni Villadoro
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Abstract

In quantum mechanics and quantum field theory perturbation theory generically requires the inclusion of extra contributions non-perturbative in the coupling, such as instantons, to reproduce exact results. We show how full non-perturbative results can be encoded in a suitable modified perturbative series in a class of quantum mechanical problems. We illustrate this explicitly in examples which are known to contain non-perturbative effects, such as the (supersymmetric) double-well potential, the pure anharmonic oscillator, and the perturbative expansion around a false vacuum.

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Marco Serone, Gabriele Spada, Giovanni Villadoro. 2016-12-13. Instantons from Perturbation Theory. https://doi.org/10.1103/physrevd.96.021701

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