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Quantum Langevin Equations and Stability

Marc-Thierry Jaekel·Serge Reynaud
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Abstract

Different quantum Langevin equations obtained by coupling a particle to a field are examined. Instabilities or violations of causality affect the motion of a point charge linearly coupled to the electromagnetic field. In contrast, coupling a scatterer with a reflection cut-off to radiation pressure leads to stable and causal motions. The radiative reaction force exerted on a scatterer, and hence its quasistatic mass, depend on the field state. Explicit expressions for a particle scattering a thermal field in a two dimensional space-time are given.

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Marc-Thierry Jaekel, Serge Reynaud. 1998-01-30. Quantum Langevin Equations and Stability. https://doi.org/10.1051/jp1:1993135

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