Relativistic tidal equations are formulated with respect to the rest frame of a central gravitational source and their solutions are studied. The existence of certain relativistic critical tidal currents are thereby elucidated. Specifically, observers that are spatially at rest in the exterior Kerr spacetime are considered in detail; in effect, these fiducial observers define the rest frame of the Kerr source. The general tidal equations for the free motion of test particles are worked out with respect to the Kerr background. The analytic solutions of these equations are investigated and the existence of a tidal acceleration mechanism is emphasized.

中文翻译：

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相对论中的临界潮汐流

相对于中心重力源的其余框架建立了相对论的潮汐方程，并研究了其解。从而阐明了某些相对论的临界潮流。具体来说，将详细考虑在外部Kerr时空处于静止状态的观察者；实际上，这些基准观察者定义了Kerr源的其余帧。针对克尔背景，得出了测试粒子自由运动的一般潮汐方程。研究了这些方程的解析解，并强调了潮汐加速机制的存在。