论文标题
Bjorken流动中的相关功能在全息schwinger-keldysh方法中
Correlation functions of the Bjorken flow in the holographic Schwinger-Keldysh approach
论文作者
论文摘要
多体物理的全息方法中的出色问题之一是对非平衡状态中相关函数的明确计算。我们提供了一个新的简单证明，即在散装中实现Thermal Schwinger-Keldysh轮廓的Crossley-Glorioso-Liu的地平帽处方与在任何任意频率和瞬时频率和动力频率下的kubo-Martin-Schwinger周期性和智障传播的Ingoing边界条件一致。对流体动力的Bjorken流的概括是通过Weyl恢复来实现的，其中双黑孔的事件范围在很晚时达到了恒定的表面重力和面积，尽管方向分别纵向和横向到流动的流动和合同。因此，双状态的温度和熵密度成为常数（而不是完美的流体膨胀），尽管很晚没有时间翻译对称性。撤消WEYL重新缩放的相关函数可以系统地计算出在大量适当的时间扩展中，这两个重新分配适当的时间参数的平均值的反向。必须将地平盖固定在非平衡事件范围内，以便满足规律性和一致性条件。因此，在完美的流体扩展的极限下，schwinger-keldysh相关功能与时空重新训练的参数在适当的温度下只是热量。通用的双局部热结构均符合所有订单。我们认为，流体动力相关函数的Stokes数据（是函数而不是常数）可以解码固定在不断发展的事件范围内的地平线帽后面的量子波动，从而解码了初始数据。
One of the outstanding problems in the holographic approach to many-body physics is the explicit computation of correlation functions in nonequilibrium states. We provide a new and simple proof that the horizon cap prescription of Crossley-Glorioso-Liu for implementing the thermal Schwinger-Keldysh contour in the bulk is consistent with the Kubo-Martin-Schwinger periodicity and the ingoing boundary condition for the retarded propagator at any arbitrary frequency and momentum. The generalization to the hydrodynamic Bjorken flow is achieved by a Weyl rescaling in which the dual black hole's event horizon attains a constant surface gravity and area at late time although the directions longitudinal and transverse to the flow expands and contract respectively. The dual state's temperature and entropy density thus become constants (instead of the perfect fluid expansion) although no time-translation symmetry emerges at late time. Undoing the Weyl rescaling, the correlation functions can be computed systematically in a large proper time expansion in inverse powers of the average of the two reparametrized proper time arguments. The horizon cap has to be pinned to the nonequilibrium event horizon so that regularity and consistency conditions are satisfied. Consequently, in the limit of perfect fluid expansion, the Schwinger-Keldysh correlation functions with space-time reparametrized arguments are simply thermal at an appropriate temperature. A generalized bilocal thermal structure holds to all orders. We argue that the Stokes data (which are functions rather than constants) for the hydrodynamic correlation functions can decode the quantum fluctuations behind the horizon cap pinned to the evolving event horizon, and thus the initial data.
