My day was dedicated to a filming crew that traveled from Japan to interview me for a science documentary about Fermi’s Paradox. As they entered my home with an expensive camera that was used to film “Top Gun”, the producer asked: “What do you think about Fermi’s question?”
I explained that the framing of Fermi’s question is arrogant, akin to a person who stays at home and wonders “Where is everybody?”, without investing effort in the search for partners. The search for extraterrestrials should be an unapologetic component of mainstream research in physics and astronomy. We would have never discovered the Higgs boson or gravitational waves without investing billions of dollars in the searches for them. Given the vastness of space and time in the cosmos, why would we presume that the answer to the most consequential question in science: “Are we not alone?”, will fall into our lap without effort? Let me be explicit: the existence of extraterrestrials is not an extraordinary claim. It is as ordinary as our own existence. Given that, it is the duty of scientists to invest resources in finding the answer.
The producer was shaken, so I tried to explain from basic principles why we should be humble as cosmic residents. Most of us never saw our inner organs, like our liver, heart, or brain, let alone figure out how they function. Yet, they constitute our physical existence. This implies that we cannot take credit for our physical abilities. Our “under the hood” physiology was handed to us by our parents like a car delivered by dealers. Over time, we get bruised and eventually we all die. Given this transient and circumstantial existence, our ego should have no place in biasing a philosophical answer to Fermi’s paradox.
Let me emphasize: these are not depressing insights. Even without a maker’s pride, it is still fun to drive a car as fast as we can. For that reason, I challenge my body every day during my morning jog.
But our existential modesty should go further. Physicists assume that there is nothing beyond the physical world. If so, our mental abilities emerge from our body and our ego cannot take credit for them either. The physical interpretation also implies that our mental states could potentially be replicated by a sufficiently complex machine with artificial intelligence (AI). Given this perspective, a brain failure is analogous to a computer crash and starvation resembles unplugging a computer from an electric outlet. These analogies come with benefits. Just as we repair or upgrade a computer, we might be able to augment or repair the human body so as to live longer than natural selection prescribed. Technological augmentation would be essential for interstellar journeys that may take millions to billions of years. If we discover long-lived interstellar visitors, we could study their material composition and get insights to futuristic technologies.
As humans, two thirds of our body mass is made of water and 89% of the water mass is oxygen. This implies that we are mostly oxygen. This fact is not surprising since oxygen is the third most abundant element in the present-day universe after hydrogen and helium. But this was not always the case. While the lightest elements, hydrogen and helium, emerged a few minutes after the Big Bang, oxygen was cooked by nuclear fusion in the hot dense cores of stars which started forming a hundred million years later. Here again, it is not surprising from the cosmological perspective that we came to exist much later. Life-as-we-know-it on Earth was an afterthought. Cosmic history was never about us because humans arrived to the scene for the last part in ten thousand of cosmic history
Given this late arrival, Enrico Fermi was probably not the most accomplished scientist who ever lived over the past 13.8 billion years after the Big Bang. There must have been more knowledgeable scientists on exoplanets, who never raised Fermi’s paradox because they figured out observationally that they are not alone. I told the NHK crew in front of their “Top Gun” camera that we are probably not the “Top Gun” of technological civilizations in our cosmic neighborhood. Since we came so late to the scene, interstellar visitors embarked on their journeys millions of years ago without having us in mind.
Investing resources in the search of extraterrestrials is worthwhile since it offers great benefits, akin to learning from a smarter student in our class of intelligent civilizations. Our current geopolitics suggests that we have a lot to learn on how to survive for a cosmologically significant time. To learn our lesson, we better look up for extraterrestrials rather than look down on each other. We should foster childlike curiosity and resist childlike bullying.
If I attended lunch at Los Alamos when Fermi asked: “Where is everybody?”, I would have answered him: “Technological signatures are subtle across astronomical distances, so we must work hard to search for them observationally. You are hereby invited to join our research team in the Galileo Project.” Fermi might have accepted my offer, since in addition to being a top-notch theorist, he was an exceptional experimentalist. During my PhD, I read a book with Fermi’s laboratory notes. His insights inspired me ever since to learn from experiments rather than from social media.
If Fermi would have joined the Galileo Project, he could have attempted to answer his own question. Science is inspired by intriguing questions, but its prestige comes from the ability to answer them. The reason I became a scientist is so that I will be able to find the answers to fundamental questions myself without relying on “the adults in the room.” Since Fermi’s question is of great importance, let’s get to work and fulfil his legacy as an experimentalist.
ABOUT THE AUTHOR
Avi Loeb is the head of the Galileo Project, founding director of Harvard University’s — Black Hole Initiative, director of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics, and the former chair of the astronomy department at Harvard University (2011–2020). He chairs the advisory board for the Breakthrough Starshot project, and is a former member of the President’s Council of Advisors on Science and Technology and a former chair of the Board on Physics and Astronomy of the National Academies. He is the bestselling author of “Extraterrestrial: The First Sign of Intelligent Life Beyond Earth” and a co-author of the textbook “Life in the Cosmos”, both published in 2021. His new book, titled “Interstellar”, was published in August 2023.