来自引力宇宙的讯息

A Message from the Gravitational Universe
Illustration Credit: NANOGrav Physics Frontier Center; Text: Natalia Lewandowska (SUNY Oswego)

Explanation: Monitoring 68 pulsars with very large radio telescopes, the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) has uncovered evidence for the gravitational wave (GW) background by carefully measuring slight shifts in the arrival times of pulses. These shifts are correlated between different pulsars in a way that indicates that they are caused by GWs. This GW background is likely due to hundreds of thousands or even millions of supermassive black hole binaries. Teams in Europe, Asia and Australia have also independently reported their results today. Previously, the LIGO and Virgo detectors have detected higher-frequency GWs from the merging of individual pairs of massive orbiting objects, such as stellar-mass black holes. The featured illustration highlights this spacetime-shaking result by depicting two orbiting supermassive black holes and several of the pulsars that would appear to have slight timing shifts. The imprint these GWs make on spacetime itself is illustrated by a distorted grid.

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来自引力宇宙的讯息
图示提供: NANOGrav Physics Frontier Center; 文稿: Natalia Lewandowska (SUNY Oswego)

说明: 北美奈赫兹引力波天文台（NANOGrav）用极大口径射电望远镜监测68颗脉冲星（波霎），并透过仔细测量脉冲到达时间的微小偏移，发现了引力波（GW）背景存在的证据。这些在不同脉冲星之间出现的相关偏移，显示它们是由引力波所引起的。而这种引力波背景，则可能是由数十万甚至数百万个超大质量黑洞双星所产生的。欧洲、亚洲和澳大利亚的团队，今天也各自报告了他们研究的成果。先前，LIGO和Virgo探测器已经量测到成对互绕大质量天体（诸如恒星级黑洞）合并时，所发出的较高频率引力波。这幅主题图示突显二颗互绕超大质量黑洞所产生的时空结构震动，以及它看似对数颗波霎的时脉所造成的扰动。这些引力波在时空结构上的印记，则是以扭曲的网格来呈现。