Rikkitic:
The fact we don't hear anyone doesn't mean a thing, except we don't hear anyone at this very narrow sliver of time.
Yeah, but it's radio, which is pretty fundamental to space flight for us. And also for modern maritime and aircraft and military operations. And for broadcast communications, although that's probably less relevant. And, without an understanding of electromagnetic waves, I doubt you could have good electrical/electronic communications over wires or fibre, let alone computers and the Internet. But yes, maybe there's some mechanism based on dark matter or quantum mechanics which we really haven't figured out, let alone used. And an alien civ has found that it's so good that they consider the whole area a child's toy.