Gravitational Waves

Like electromagnetic waves, gravitational waves could be used to carry information over great distances, and have the advantage of reduced scattering due to their long wavelengths. Further, unlike optical or radio communications, gravitational waves have little background noise to contend with. The disadvantage of gravitational waves, and it's a big one, is the energy and technological sophistication required to harvest them, which is presumably out of reach of all but the most advanced civilizations.

Detectability

  • Gravitational waves have only recently become detectable by instruments such as the Laser Interferometer Gravitational-Wave Observatory (LIGO).