Searching for Intelligent Life in Gravitational Wave Signals Part I: Present Capabilities and Future Horizons

We show that the Laser Interferometer Gravitational Wave Observatory (LIGO) is a powerful instrument in the Search for Extra-Terrestrial Intelligence (SETI). LIGO's ability to detect gravitational waves (GWs) from accelerating astrophysical sources, such as binary black holes, also provides the potential to detect extra-terrestrial mega-technology, such as Rapid And/or Massive Accelerating spacecraft (RAMAcraft). We show that LIGO is sensitive to RAMAcraft of 1 Jupiter mass accelerating to a fraction of the speed of light (e.g. 10%) up to about 100kpc.

https://arxiv.org/abs/2212.02065