标题： 非线性引力波记忆的持续性 显示英文标题

标题： The Persistence of Nonlinear Gravitational Wave Memory

摘要： 非线性引力波记忆是理论物理的一个意外发现。 尽管人们知道引力波会在一组自由下落的测试质量中引起振荡的挤压和拉伸运动，但令人意外的是，这种波会使测试质量产生残留位移。 这种位移是对经过的引力波的纪念。 这种记忆起源于引力的非线性特性。 虽然合并的黑洞是引力波的重要来源，但引力波本身的能量也是引力波的另一个来源。 通常将这种记忆描述为由主要引力波爆发引起的测试质量的永久位移。 但正如我们所展示的，在回声的海洋中，记忆在晚期会消失。 显示英文摘要

摘要： Nonlinear gravitational wave memory is a surprise of theoretical physics. Whereas it is understood that a gravitational wave induces oscillatory squeezing and stretching motion in a collection of freely-falling test masses, it is unexpected that the wave leaves a residual displacement of the test masses. This displacement is the tribute in memoriam to the passing wave. The memory originates in a nonlinear feature of gravitation. Whilst merging black holes are a significant source of gravitational waves, the gravitational wave energy itself is a further source of gravitational waves. The memory is often described as a permanent displacement of the test masses caused by a burst of primary gravitational waves. But as we show, memory vanishes at late times in a sea of echoes.