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arXiv · 1806.00943

Discrete worldline instantons

Christian Schneider·Greger Torgrimsson·Ralf Schützhold
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Abstract

The semiclassical approximation of the worldline path integral is a powerful tool to study nonperturbative electron-positron pair creation in spacetime-dependent background fields. Finding solutions of the classical equations of motion, i.e. worldline instantons, is possible analytically only in special cases, and a numerical treatment is nontrivial as well. We introduce a completely general numerical approach based on an approximate evaluation of the discretized path integral that easily and robustly gives the full semiclassical pair production rate in nontrivial multi-dimensional fields, and apply it to some example cases.

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Christian Schneider, Greger Torgrimsson, Ralf Schützhold. 2018-07-01. Discrete worldline instantons. https://doi.org/10.1103/physrevd.98.085009

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