Cosmological memory effect
Cosmological memory effect
复制标题
宇宙记忆效应
DOI：
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发表时间：
2016
期刊：
影响因子：
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通讯作者：
R. Wald
中科院分区：
文献类型：
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作者：
Alexander Tolish;R. Wald
“记忆效应”是由于引力辐射的通过而导致的试验粒子相对分离的永久性变化。我们研究了一般的，空间平坦的Friedmann-Lemaitre-Robertson-Walker（FLRW）宇宙学的记忆效应，通过考虑与涉及粒子源的发射事件相关的辐射。我们发现，如果所产生的扰动分解成标量，矢量和张量部分，只有张量部分有助于记忆。此外，张量对记忆的贡献只取决于源和观测事件的宇宙学标度因子，而不取决于宇宙详细的膨胀历史。特别是，对于相同光度距离的光源，在空间平坦的FLRW时空中的记忆效应比闵可夫斯基情形增强了（1+z）倍。
The “memory effect” is the permanent change in the relative separation of test particles resulting from the passage of gravitational radiation. We investigate the memory effect for a general, spatially flat Friedmann-Lemaitre-Robertson-Walker (FLRW) cosmology by considering the radiation associated with emission events involving particle-like sources. We find that if the resulting perturbation is decomposed into scalar, vector, and tensor parts, only the tensor part contributes to memory. Furthermore, the tensor contribution to memory depends only on the cosmological scale factor at the source and observation events, not on the detailed expansion history of the universe. In particular, for sources at the same luminosity distance, the memory effect in a spatially flat FLRW spacetime is enhanced over the Minkowski case by a factor of (1+z).