A stochastic background of gravitational waves could be created by the superposition of a large number of independent sources. The physical processes occurring at the earliest moments of the universe certainly created a stochastic background that exists, at some level, today. This is analogous to the cosmic microwave background, which is an electromagnetic record of the early universe. The recent observations of gravitational waves by the Advanced LIGO and Advanced Virgo detectors imply that there is also a stochastic background that has been created by binary black hole and binary neutron star mergers over the history of the universe. Whether the stochastic background is observed directly, or upper limits placed on it in specific frequency bands, important astrophysical and cosmological statements about it can be made. This review will summarize the current state of research of the stochastic background, from the sources of these gravitational waves to the current methods used to observe them.

引力波的随机背景可以通过大量独立源的叠加而产生。发生在宇宙最早时刻的物理过程无疑创造了一个随机背景，在某种程度上，今天存在。这类似于宇宙微波背景，它是早期宇宙的电磁记录。高级 LIGO 和高级室女座探测器最近对引力波的观测表明，在宇宙历史上，双黑洞和双中子星合并还产生了一个随机背景。无论是直接观察随机背景，还是在特定频段对其设置上限，都可以对其进行重要的天体物理学和宇宙学陈述。