These guys must be fun at parties. Astrobiologists Aditya Chopra and Charley Lineweaver said in their recent study that the reason why aliens haven’t made contact with us is because they’re all dead.
“Our suggestion that the universe is filled with dead aliens might disappoint some, but the universe is under no obligation to prevent disappointment,” they wrote in their study—probably before dropping the mic.
Scientists have long believed that we are not alone in the universe, with billions of planets in the Milky Way alone capable of supporting life. And if life can be supported, the thinking goes, then life should—microorganisms should evolve into multicellular lifeforms, eventually giving rise to life intelligent enough to send and receive radio signals, or maybe even travel in space.
But Chopra and Lineweaver argue otherwise, saying that “early extinction could be the cosmic default for life in the universe.” Using the Gaia hypothesis (which states that microorganisms interact with their environment to form a self-regulating system, making it habitable), they note that even if such organisms existed, the chances of them evolving in time to regulate a planet’s environment are slim.
Without this regulation, more complex multicellular organisms are unlikely to appear. So what you’re left with are just a bunch of dead alien microorganisms battered into submission by the harsh environments they emerged in.
“Even if life does emerge on a planet, it rarely evolves quickly enough to regulate greenhouse gases, and thereby keep surface temperatures compatible with liquid water and habitability,” Chopra and Lineweaver said in their study.
They must have then found another mic, and dropped it again. “Maintaining life on an initially wet rocky planet in the habitable zone may be like trying to ride a wild bull. Most riders fall off.”
Chopra and Lineweaver’s study is unlikely to make SETI researchers find something else to do with their lives, but without evidence proving or disproving the existence of intelligent extraterrestrial life, these ‘false starts’ seem at least as likely as extra-terrestrial life being ‘out there.