On Thu, Jan 5, 2017 at 8:24 PM, Bob Higgins <[email protected]> wrote:
There is a more far fetched possibility - that of communications via > gravitational waves. There have been a number of papers talking about the > conversion of EM waves into gravitational waves in certain types of > superconductors. If that ever proves to be possible, it would open a whole > new spectrum - one that could harbor SETI communications. > Because gravity appears to have infinite range, assuming there are gravitons, they are expected to be massless. This means they will travel at the speed of light. From this PhysicsForums post [1], I infer that for masses under human control which would serve as the source of the gravitons, they will have very large wavelengths. Is there a way to send lots of information over a signal with a very low frequency? Gravitons aside, if the alien signal is spread across a spectrum, as you mention, I suppose it might be very difficult to detect. If the transmitted signal further involves intentionally taking the background noise and making small adjustments to it, you would probably have to be looking for this kind of pattern specifically to determine that there was a signal at all. Eric [1] https://www.physicsforums.com/threads/graviton-energy-and-frequency-wavelength.242145/#post-1780881
