What are the advantages of using gravitational waves for communication? They seem incredibly difficult to produce or detect, and don't travel any faster in a vacuum than electromagnetic waves.
Do they potentially propagate through matter with less interference than electromagnetic waves? I have no idea, that would be the only thought.. otherwise yeah I don't see what the appeal would be.. and how the hell do you create them on any small scale that can be actually read by someone, since gravity is such a weak force?
No, both gravitational waves and electromagnetic waves decrease in intensity with the square of distance.
(This is true of any wave in 3D space, because the area covered by a wavefront increases with the square of distance. The inverse square law is a consequence of conservation of energy.)
The energy of the gravitational waves will decrease with the square of the distance, but the amplitude will not. We can detect this in LIGO. This amplitude is also known as "strain". For more discussion check this page: http://spiff.rit.edu/classes/ast613/lectures/grav_i/grav_i.h...
The same is true of electromagnetic waves. The amplitude of EM waves decreases inversely with distance, and the energy decreases with the inverse square.
Your original comparison of EM waves to gravitational waves is only possible because you looked at the power of one, and the amplitude of the other. If you compare apples to apples, they're the same.
A question for typon: in light of this information, do you still believe that advanced enough civilizations would use gravitational waves for communication?