Perimeter Institute for Theoretical Physics, Waterloo, Ontario N2L2Y5, Canada.
University of Guelph, Guelph, Ontario N2L3G1, Canada.
Phys Rev Lett. 2018 Aug 17;121(7):071102. doi: 10.1103/PhysRevLett.121.071102.
Gravitational memory is an important prediction of General Relativity, which is intimately related to asymptotic symmetries at null infinity and the so-called soft graviton theorem. For a given transient astronomical event, the angular distribution of energy and angular momentum fluxes uniquely determine the displacement and spin memory effect in the sky. We investigate the possibility of using the binary black hole merger events detected by Advanced LIGO/Virgo to test the relation between the source's energy emission and the gravitational memory measured on Earth, as predicted by General Relativity. We find that while it is difficult for Advanced LIGO/Virgo one-year detection of a third-generation detector network will easily rule out the hypothesis assuming isotropic memory distribution. In addition, we construct a phenomenological model for memory waveforms of binary neutron star mergers and use it to address the detectability of memory from these events in the third-generation detector era. We find that measuring gravitational memory from neutron star mergers is a possible way to distinguish between different neutron star equations of state.
引力记忆是广义相对论的一个重要预测，它与无穷远的渐近对称性和所谓的软引力子定理密切相关。对于给定的瞬态天文事件，能量和角动量通量的角分布唯一地确定了天空中的位移和自旋记忆效应。我们研究了利用先进的 LIGO/Virgo 探测到的双黑洞合并事件来检验广义相对论预测的源能量发射与地球上测量的引力记忆之间的关系的可能性。我们发现，虽然对于先进的 LIGO/Virgo 来说，一年的检测很难，但第三代探测器网络的检测很容易排除假设的各向同性记忆分布的假说。此外，我们构建了一个双中子星合并的记忆波现象模型，并利用它来解决第三代探测器时代这些事件的记忆可探测性问题。我们发现，从中子星合并中测量引力记忆是区分不同中子星物态方程的一种可能方法。
