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arXiv · 0804.1360

Brownian Motion in Robertson-Walker Space-Times from electromagnetic Vacuum Fluctuations

Carlos H. G. Bessa·Valdir B. Bezerra·L. H. Ford
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Abstract

We consider classical particles coupled to the quantized electromagnetic field in the background of a spatially flat Robertson-Walker universe. We find that these particles typically undergo Brownian motion and acquire a non-zero mean squared velocity which depends upon the scale factor of the universe. This Brownian motion can be interpreted as due to non-cancellation of anti-correlated vacuum fluctuations in the time dependent background space-time. We consider several types of coupling to the electromagnetic field, including particles with net electric charge, a magnetic dipole moment, and electric polarizability. We also investigate several different model scale factors.

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Carlos H. G. Bessa, Valdir B. Bezerra, L. H. Ford. 2008-04-08. Brownian Motion in Robertson-Walker Space-Times from electromagnetic Vacuum Fluctuations. https://doi.org/10.1063/1.3133946

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