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arXiv · 0908.1470

Stochastic String Motion Above and Below the World Sheet Horizon

Jorge Casalderrey-Solana·Keun-Young Kim·Derek Teaney
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Abstract

We study the stochastic motion of a relativistic trailing string in black hole AdS_5. The classical string solution develops a world-sheet horizon and we determine the associated Hawking radiation spectrum. The emitted radiation causes fluctuations on the string both above and below the world-sheet horizon. In contrast to standard black hole physics, the fluctuations below the horizon are causally connected with the boundary of AdS. We derive a bulk stochastic equation of motion for the dual string and use the AdS/CFT correspondence to determine the evolution a fast heavy quark in the strongly coupled $\N=4$ plasma. We find that the kinetic mass of the quark decreases by $\Delta M=-\sqrt{\gamma \lambda}T/2$ while the correlation time of world sheet fluctuations increases by $\sqrt{\gamma}$.

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Jorge Casalderrey-Solana, Keun-Young Kim, Derek Teaney. 2009-08-11. Stochastic String Motion Above and Below the World Sheet Horizon. https://doi.org/10.1088/1126-6708/2009/12/066

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