|
Several authors postulate the need for continuous growth (expansion into the universe) if life is to continue. I recall at least one who suggested that expansion would accelerate to near light-speed because of how resources get consumed. The alternative is reduced energy consumption to stay 'local' but alive (is a VERY slow-running uploaded self still "alive?"). Even Dyson ring/sphere/section energy collection doesn't work over billions of years. Your star runs out of fuel.
Along the Fermi lines, it is hard to imagine a continuously expanding alien race whose RF signature is so low-profile we haven't spotted it yet. I suppose one answer is to say they intentionally keep a low profile, so as to sneak up on their expansion targets. Another is to say that we DO see them but interpret them as natural, cosmological oddities like quasars. Another is to say the laws of physics vary enough across the universe that we don't see their society's emissions (and I don't believe science ruled this one out yet).
|