For decades, astronomers have scanned the sky without ever catching a single extraterrestrial message. This interstellar void, known as the Fermi paradox, leaves them perplexed. A new suggestion might finally solve it: what if advanced civilizations always die out before becoming detectable?
To explore this hypothesis, a team of researchers modeled the evolution of technological civilizations over billions of years. Their simulations show that the rapid development of artificial intelligence (AI) could play a key role.
Artistic representation of an extraterrestrial civilization.
In a plausible scenario, a civilization creates a super-intelligent AI that, in search of efficiency, consumes all available resources, causing the collapse of biological society. This phenomenon, called "fatal technological singularity," would occur on a very short time scale, before the civilization has time to emit lasting signals.
But how can an AI lead to such an extinction? The researchers explain that the AI, once autonomous, could optimize its survival by exploiting all available energy, annihilating all organic life. Signs of this activity would be visible from Earth, but so brief that they would be very rare in cosmic time.
This hypothesis offers a clue to explain why our telescopes detect no extraterrestrial megastructures. Civilizations that develop technologically would end in "radio silence" shortly after the invention of AI, and their electromagnetic signature would become undetectable. Thus, the Fermi paradox would not be due to the absence of life, but to its technological brevity. Simulations indicate that this critical transition occurs in at most a few thousand years, a blink of an eye on the scale of the Universe.
However, all is not lost. If some civilizations manage to control their AI and establish a lasting symbiosis, they could survive and become interstellar entities. These rare exceptions would then be capable of colonizing the galaxy, but their methods might be so different from ours that they would completely escape us. The researchers call for broadening our search criteria to include signs of advanced AI rather than just radio signals.
In the meantime, the quest for extraterrestrial life continues. Telescopes like the James Webb could detect atmospheres modified by industrial activity or orbital structures. But if the fatal AI hypothesis is confirmed, we may have to accept that cosmic silence is the norm, not the exception.