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arXiv 0903.1840hep-thhep-ph
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AdS/CFT的随机尾弦和Langevin动力学

Stochastic trailing string and Langevin dynamics from AdS/CFT

G. C. Giecold, E. Iancu, A. H. Mueller

摘要:

利用规范/弦对偶性,我们导出了描述相对论性重夸克在有限温度下以恒定平均速率运动通过强耦合N=4 SYM等离子体的动力学的朗之万方程.我们证明了随机性产生于弦世界片视界,因而在时空度规中与黑洞视界因果地断开。这暗示了涨落的非热性质,这一事实进一步支持了朗之万方程中的噪声项和阻力不服从爱因斯坦关系。我们提出了一个重夸克动力学的物理图像,其中耗散和波动被解释为介质感应辐射和相关的量子力学波动。这幅图提供了正确的阻力和(纵向和横向)动量加宽系数的参数估计。

英文摘要:

Using the gauge/string duality, we derive a set of Langevin equations describing the dynamics of a relativistic heavy quark moving with constant average speed through the strongly-coupled N=4 SYM plasma at finite temperature. We show that the stochasticity arises at the string world-sheet horizon, and thus is causally disconnected from the black hole horizon in the space-time metric. This hints at the non-thermal nature of the fluctuations, as further supported by the fact that the noise term and the drag force in the Langevin equations do not obey the Einstein relation. We propose a physical picture for the dynamics of the heavy quark in which dissipation and fluctuations are interpreted as medium-induced radiation and the associated quantum-mechanical fluctuations. This picture provides the right parametric estimates for the drag force and the (longitudinal and transverse) momentum broadening coefficients.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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