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arXiv · 1001.2559

Capacitor Discharge and Vacuum Resistance in Massless QED_2

Yi-Zen Chu·Tanmay Vachaspati
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Abstract

A charged parallel plate capacitor will create particle-antiparticle pairs by the Schwinger process and discharge over time. We consider the full quantum discharge process in 1+1 dimensions including backreaction, when the electric field interacts with massless charged fermions. We recover oscillatory features in the electric field observed in a semiclassical analysis and find that the amplitude of the oscillations falls off as t^{-1/2} and that stronger coupling implies slower decay. Remarkably, Ohm's law applies to the vacuum and we evaluate the quantum electrical conductivity of the vacuum to be e/\pi^{1/2}, where e is the fermionic charge. Similarities and differences with black hole evaporation are mentioned.

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Yi-Zen Chu, Tanmay Vachaspati. 2010-01-14. Capacitor Discharge and Vacuum Resistance in Massless QED_2. https://doi.org/10.1103/physrevd.81.085020

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