Cosmic string networks are expected to generate a characteristic stochastic gravitational wave background that may be within the reach of current and upcoming gravitational wave detectors. A detection of this spectrum would provide invaluable information about the physics of the early universe, as it would allow us to probe the sequence of phase transitions that happened in the distant past. Here, I review the emission of gravitational waves by Nambu–Goto cosmic strings—thin cosmic strings that couple strongly to gravity only—and by superconducting strings—strings that carry electromagnetic currents. A comparison between the stochastic gravitational wave background predicted in these two very distinct string-forming scenarios reveals that this spectrum may have signatures that may allows us to discriminate between them observationally. The stochastic gravitational wave background generated by cosmic string networks may then enable us to uncover not only the energy-scale of the string-forming phase transition, but the underlying particle physics scenario as well.

宇宙弦网络预计将产生特征随机引力波背景，该背景可能在当前和即将推出的引力波探测器的范围内。对该光谱的探测将提供有关早期宇宙物理学的宝贵信息，因为它将使我们能够探测遥远过去发生的相变序列。在这里，我回顾了南部-后岛宇宙弦（仅与重力强烈耦合的细宇宙弦）和超导弦（携带电磁电流的弦）发射的引力波。在这两种截然不同的弦形成场景中预测的随机引力波背景之间的比较表明，该频谱可能具有使我们能够在观测上区分它们的特征。由宇宙弦网络产生的随机引力波背景可能使我们不仅能够揭示弦形成相变的能量尺度，而且还能揭示潜在的粒子物理场景。