Comic book writer Warren Ellis put this idea in his version of the Marvel first family, the Fantastic Four: what if the answer to the Fermi Paradox was really, really awful? The Fermi paradox is the discrepancy between the lack of conclusive evidence of advanced extraterrestrial life and the apparently high likelihood of its existence. If the universe is so big, and life is seemingly so easy, then where is everybody? The answer in the Fantastic Four was: Galactus devours civilizations before they reach a level of technology that would allow them to communicate with each other. For those of us living outside any Marvel Universe, the answer may be a lot less devastating. Here’s more from Centauri Dreams:
Brian Lacki (UC-Berkeley) looked into the matter in detail at a Breakthrough Discuss meeting in 2021. Lacki points out that our use of radio takes up 100,000,000th of the lifespan of the Sun. We must think, he believes, in terms of temporal coincidence, as the graph he presented at the meeting shows. Note the arbitrary placement of a civilization at Centauri B, and others at Centauri A and C, along with our own timeline. The thin line representing our civilization actually corresponds to a lifetime of 10 million years. What are the odds that the lines of any two stars coincide? Faint indeed, unless societies can persist for not just millions but even billions of years. We don’t know if they can, but we need to think about it in terms of what we might receive.
But there is another point. Should we assume that stars near the Sun are roughly the same age as ours? You might think so at first glance, given the likely formation of our star in a stellar cluster, but in fact clusters separate and diverge over time, so that finding the Sun’s birthplace and its siblings is challenging in itself (though some astronomers are trying). As we’re also learning, slowly but surely, stars around us in the Milky Way’s so-called ‘thin disk’ – within which the Sun moves – actually show a wider range of ages than we first thought.