Hi sparrowdown,
I'm still sticking to Morgan Freeman. Picture the scene, a sailboat on a clear lake. Morgan's silky smooth voice narrates:
Visualize the luffing of a sail as a sailboat comes about or tacks. The waves in the sail’s fabric are similar in many ways to gravitational waves, but instead of sailcloth fabric, gravitational waves move through a “fabric” of space. Einstein called this fabric the “space-time continuum” in his 1916 work known as General Relativity. Although this theory is very sophisticated, the concept is relatively simple.
Scene cuts to a busy New York intersection:
This fabric is four dimensional. It has the three usual dimensions of space—east-west, north-south, and up down—plus the fourth dimension of time. Here is an example: we define a location on this “fabric” as 5th Street and Third Avenue on the forth floor at 9 AM. We can’t see this “fabric,” just as we can’t see wind, sound, or gravity for that matter. Nevertheless, those elements are real, and so is this “fabric.” If we could generate ripples in this space-time fabric, many applications would become available to us. Much like radio waves can be used to transmit information through space, we could use gravitational waves to perform similar functions...
To be continued...in 2019