ETs have a thing for self-annihilation.
In a 2020 study, researchers suggest the answer to the Fermi paradox could be pretty bleak: Maybe all the intelligent civilizations have annihilated themselves. Jeez, 2020, that’s a little on the nose.
This is the Fermi paradox stated at its most succinct: The universe is unfathomably gigantic, but so far, we’ve never seen any sign that there’s intelligent life anywhere else.
We’ve never observed an extraterrestrial living thing, or uncovered any evidence for extinct ones. As we peer further out into our corner of the universe using more and more powerful telescopes, for example, people continue to hold out hope that we’ll find evidence of a civilization, Dyson sphere, or anything just around the next corner.
But there’s a problem with that line of thinking. A civilization that we’d see from this far away, let alone one that could have built something like a Dyson sphere, is likely to be peering back at us.
Why aren’t they sending telescope satellites through our part of space? And how can it be that out of all the planets and systems we’ve peeked into so far, we’ve seen nothing?
There are as many individual theories as there are theorists, and these run a huge gamut.
“The existence of extraterrestrial intelligence is directly related to habitability and a galactic habitable zone (GHZ); where habitable planets are located and where potential life are most likely to form,” the new study's researchers (three Caltech physicists and one high school student), write:
“Overall, previous studies of habitability and the likelihood of intelligent life have provided many valuable insights; however, the precise propensity of galactic intelligent life to emerge has not yet been explored with spatial and temporal analysis, nor has any research explicitly estimated an age distribution for potential life within the Galaxy.”
These researchers wanted to add nuance to the discussion by increasing the depth of their analysis, and they wanted to gauge how relatively “old” any alien civilizations are likely to be. This is a critical factor in whether or not a civilization can even travel in space or put out intergalactic feelers, because they can only do that from a key “sweet spot.”
Too young, and, like us before very recently, they simply won’t have the means yet. Too old, and they could be stripped of technology in a post-apocalyptic burnout.
They could even be extinct. In fact, the research includes parameters for extinction and the idea of “self annihilation,” a probability that could be extraordinarily high.
“Since we cannot preclude the high possibility of annihilation, [this result] suggests that most of the potential complex life within the Galaxy may still be very young,” the scientists explain. That means there could be a proliferation, but it’s of other civilizations that can’t push out into the galaxy yet—just like us.
What’s the point of research like this? It’s fair to ask, the same way it’s fair to ask questions about projects like SETI, the Search for Extra Terrestrial Intelligence, in the first place.
But these researchers have a clear goal, which is to place a touchstone for others who want to continue to explore the Fermi paradox. They explain:
“The exact number of the intelligent life estimated here is not the focus of our work. [R]ather, it is instead the development of a statistical, comprehensive galactic picture tracing the potential growth propensity of intelligent life over a course of ~20 billion years.”
Indeed, we don’t know what’s hiding around the next intergalactic corner.
