Diffusion in an Expanding Plasma using AdS/CFT
Abstract
We consider the diffusion of a non-relativistic heavy quark of fixed mass M, in a one-dimensionally expanding and strongly coupled plasma using the AdS/CFT duality. The Green's function constructed around a static string embedded in a background with a moving horizon, is identified with the noise correlation function in a Langevin approach. The (electric) noise decorrelation is of order 1/T(\tau) while the velocity de-correlation is of order MD(\tau)/T(\tau). For MD>1, the diffusion regime is segregated and the energy loss is Langevin-like. The time dependent diffusion constant D(\tau) asymptotes its adiabatic limit 2/\pi\sqrt{\lambda} T(\tau) when \tau/\tau_0=(1/3\eta_0\tau_0)^3 where \eta_0 is the drag coefficient at the initial proper time \tau_0.
Cite
@article{arxiv.0707.0601,
title = {Diffusion in an Expanding Plasma using AdS/CFT},
author = {Keun-Young Kim and Sang-Jin Sin and Ismail Zahed},
journal= {arXiv preprint arXiv:0707.0601},
year = {2008}
}
Comments
19 pages, 2 figures, minor corrections, version to appear in JHEP