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arXiv · 2605.02570

Revisiting semiclassical scalar QED in 1+1 dimensions

Santiago Sanz-Wuhl·Jochen Zahn
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Abstract

We study the backreaction of a charged scalar quantum field in the presence of two opposite charges placed at the boundaries of a finite one-dimensional region, with attention to boundary effects. We review, correct, and extend previous corresponding work of Ambj{\o}rn \& Wolfram \cite{ambjorn_properties_1983}. Despite notable differences, our analysis confirms the mechanism, discussed by Ambj{\o}rn \& Wolfram, by which the incorporation of backreaction avoids certain instabilities. We also observe the interesting phenomenon of ``over-screening'', by which for high external charges an increase of the external charges leads to a decrease of the electric field between the two charges.

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Santiago Sanz-Wuhl, Jochen Zahn. 2026-05-04. Revisiting semiclassical scalar QED in 1+1 dimensions. https://arxiv.org/abs/2605.02570

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