Thank you. But I think some overlap should apply between intelligent civilizations <i>seeking</i> to communicate:<br>- the promiscuity of carbon<br>- the observed expansion of the universe<br>"Other dimensions" aside, there should be some Rosetta stone among spacefaring species, where we have observations in common including physics, chemistry, and cosmology. (This would include substrates that allow computation, so we should have computers in common, in some form.)<br>Of course, yes: If elite species have no interest in communicating on a band detectable by our current technology, then we should be unsurprised not to hear them. (And, of course, if the speed of light turns out to be insurmountable for practical purposes, then most of us will never learn of one another, regardless.)