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arXiv · 1711.07712

The Thin-Wall Approximation in Vacuum Decay: a Lemma

Adam R. Brown
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Abstract

The 'thin-wall approximation' gives a simple estimate of the decay rate of an unstable quantum field. Unfortunately, the approximation is uncontrolled. In this paper I show that there are actually two different thin-wall approximations and that they bracket the true decay rate: I prove that one is an upper bound and the other a lower bound. In the thin-wall limit, the two approximations converge. In the presence of gravity, a generalization of this lemma provides a simple sufficient condition for non-perturbative vacuum instability.

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Adam R. Brown. 2017-11-21. The Thin-Wall Approximation in Vacuum Decay: a Lemma. https://doi.org/10.1103/physrevd.97.105002

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