paper

The tunneling decay rate in QFT beyond the thin wall approximation

arXiv:2512.12161 · doi:10.1209/0295-5075/ae1a14

Abstract

The tunneling decay rate per unit volume in Quantum Field Theory (QFT), at order , is given by , where is the Euclidean action evaluated at the so-called bounce, and is proportional to the determinant of a second-order differential operator. The dominant contribution comes from the exponential factor. To estimate , one must determine the bounce configuration, which satisfies a highly nonlinear equation. A common approach in the literature is the thin-wall approximation. In this work, we extend the formalism to cases where the thin-wall approximation is not valid. We employ a simple variational method to estimate both the bounce and the decay rate, and we find good agreement between our results and full numerical calculations.

6 pages, 2 figures

References in corpus (8)