Aliens, probability, physics—it might not sound like the most simple or most interesting of concepts, but the Fermi paradox poses perhaps one of the most existential questions of all time: are we alone in the universe?
Although commonly associated to Fermi, the question of probability in relation to extra-terrestrial life was first questioned in 1933 by Soviet scientist and astronautic pioneer Konstantin Tsiolkovsky, who stated that those who deny the existence of such life relied on the belief that if aliens did exist they would have a) visited us on Earth, and b) given us some sign, no matter how small, of their existence. Tsiolkovsky then proposed the zoo hypothesis, which is perhaps even more existential than the Fermi paradox all together.
“The Fermi paradox poses perhaps one of the most existential questions of all time”
The paradox, named after Italian physicist Enrico Fermi, first arose in 1950. Fermi, also known as the creator of the world’s first nuclear reactor and the winner of the 1938 Nobel Prize in Physics, was discussing a recent increase in UFO sightings in New Mexico, and questioned three primary things: the probability of planets that were like Earth, the probability of life on those planets, and the rise and duration of modern technology.
Fermi, along with American astrophysicist Michael H. Hart, argued the following:
1) Of the billions of stars in the galaxy that are similar to our Sun, there are billions of these which are older than our Solar system.
2) There is high probability that some of these stars must have Earth-like planets which may have the right conditions to allow for the development of intelligent life.
3) Some of these civilizations of intelligent life may have developed interstellar travel, and must have been able to cross the Milky Way in the millions of years that they have existed.
Thus, Fermi argued, humans on Earth should have already been visited by UFOs.
“The ‘Greater Filter’ theory argues that intelligent life regularly destroys itself before it can develop interstellar technology”
There are many hypothetical explanations for the paradox. The most obvious are that intelligent life is extremely rare, or that there is a lack of alien technology advanced enough to facilitate such travel or communication. However, there are also more complex or existential suggestions. For example, the ‘Great Filter’ theory argues that intelligent life regularly destroys itself before it can develop interstellar technology, while the SETI Paradox suggests that all civilizations are listening for UFO communication, but that none, or very few, are successfully transmitting. Meanwhile, perhaps more uncanny theories include that Earth has been deliberately ignored, or that UFOs are already here among us without our knowing.
These theories all present viable reasons for why, against high probability, we have not knowingly found life beyond that which is on our planet. The paradox does have scientific grounding, and has prompted astrophysicists across the globe to seek out alien life. While conspiracy theories run amok, the possibility of life on a planet other than our own is a genuine scientific question. Physicist Brian Cox famously agreed with the Great Filter theory in 2016, arguing that humans were already ‘approaching that position’ of self-destruction. In comparison, when the CIA quietly released over 800,000 files in 2017, it was found that from 2007-2012, over $22 million a year had been spent on investigating UFOs.
“Whether there is life out there or not, humans have long looked to see if they are alone in the universe”
The fact is, whether there is life out there or not, humans have long looked to see if they are alone in the universe. When we were not satisfied with each other, and then too with the creatures we share our planet with, we looked to the stars. Humanity has gazed up into the cosmos and looked for signs of life other than our own since ancient times. Ancient civilizations based entire calendars and religions around the stars and what they believed lay beyond. And in the 21st century, as we continue to develop methods that might one day take us out of our own solar system, it is clear this fascination is still clear.
The Fermi Paradox poses endless questions about our place in the universe, but provides very few answers. Are we alone? Would we want to be visited? Or are we aliens ourselves, sent here by our distant alien ancestors? It’s difficult to explain away, but certainly fun to entertain.