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arXiv · 1308.4794

Langevin description of gauged scalar fields in a thermal bath

Yuhei Miyamoto·Hayato Motohashi·Teruaki Suyama·Jun'ichi Yokoyama
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Abstract

We study the dynamics of the oscillating gauged scalar field in a thermal bath. A Langevin type equation of motion of the scalar field, which contains both dissipation and fluctuation terms, is derived by using the real-time finite temperature effective action approach. The existence of the quantum fluctuation-dissipation relation between the non-local dissipation term and the Gaussian stochastic noise terms is verified. We find the noise variables are anti-correlated at equal-time. The dissipation rate for the each mode is also studied, which turns out to depend on the wavenumber.

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Yuhei Miyamoto, Hayato Motohashi, Teruaki Suyama, Jun'ichi Yokoyama. 2013-10-29. Langevin description of gauged scalar fields in a thermal bath. https://doi.org/10.1103/physrevd.89.085037

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