近日，美国加州理工学院的Yiwen Zhang及其研究团队取得一项新进展。经过不懈努力，他们对来自引力冲击波的伦德勒流体进行研究。相关研究成果已于2024年5月30日在国际知名学术期刊《高能物理杂志》上发表。

该研究团队研究了闵可夫斯基时空中伦德勒视界附近的，引力激波几何及其流体描述之间的对应关系。利用描述洛伦兹空间代数对称性的彼得罗夫分类，研究人员建立了势流体和冲击波度量摄动之间的显式映射，其中冲击波几何的爱因斯坦方程等效于流体的不可压缩性条件，由冲击波源增强。然后研究人员考虑了势流体的随机量子源Ansatz，它为真空能量波动所产生的冲击波提供了物理解释。

在这种设定下，爱因斯坦方程（或等价地，流体的不可压缩性条件）转化为一个随机微分方程。通过用普朗克宽度(类似于膜范式)以洛伦兹不变的方式将量子源拖尾在拉伸视界上，研究人员对伦德勒视界附近的波动进行积分，以找到横越因果金刚石视界的光子往返时间方差的累积效应。

附：英文原文

Title: Rindler fluids from gravitational shockwaves

Author: Bak, Sang-Eon, Keeler, Cynthia, Zhang, Yiwen, Zurek, Kathryn M.

Issue&Volume: 2024-05-30

Abstract: We study a correspondence between gravitational shockwave geometry and its fluid description near a Rindler horizon in Minkowski spacetime. Utilizing the Petrov classification that describes algebraic symmetries for Lorentzian spaces, we establish an explicit mapping between a potential fluid and the shockwave metric perturbation, where the Einstein equation for the shockwave geometry is equivalent to the incompressibility condition of the fluid, augmented by a shockwave source. Then we consider an Ansatz of a stochastic quantum source for the potential fluid, which has the physical interpretation of shockwaves created by vacuum energy fluctuations. Under such circumstance, the Einstein equation, or equivalently, the incompressibility condition for the fluid, becomes a stochastic differential equation. By smearing the quantum source on a stretched horizon in a Lorentz invariant manner with a Planckian width (similarly to the membrane paradigm), we integrate fluctuations near the Rindler horizon to find an accumulated effect of the variance in the round-trip time of a photon traversing the horizon of a causal diamond.

DOI: 10.1007/JHEP05(2024)331

Source: https://link.springer.com/article/10.1007/JHEP05(2024)33