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arXiv · 0707.0601

Diffusion in an Expanding Plasma using AdS/CFT

Keun-Young Kim·Sang-Jin Sin·Ismail Zahed
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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(τ) while the velocity de-correlation is of order MD(τ)/T(τ). For MD>1, the diffusion regime is segregated and the energy loss is Langevin-like. The time dependent diffusion constant D(τ) asymptotes its adiabatic limit 2/π\sqrtλ T(τ) when τ/τ_0=(1/3η_0τ_0)^3 where η_0 is the drag coefficient at the initial proper time τ_0.

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Keun-Young Kim, Sang-Jin Sin, Ismail Zahed. 2008-04-09. Diffusion in an Expanding Plasma using AdS/CFT. https://doi.org/10.1088/1126-6708%2F2008%2F04%2F047

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