Most movies have alien life coming to Earth – whether for resources, to pick a fight, or just hang out – and though there is a massive technological gap between us, we always overcome through the power of love, or whatever.
In the 1950s a group of scientists sat down for lunch at the Los Alamos National Laboratory in New Mexico, the same place where Oppenheimer and friends built the atomic bomb a decade earlier. This is where Enrico Fermi, an Italian scientist who had won the Nobel Prize in Physics, and is regarded as one of the chief architects of the nuclear age asked, “Where is everybody?”
The probability of Earth-like planets and the sheer population of celestial bodies in the universe means that humans should have been visited by now. Loads of times. And yet, no one has come.
If interstellar travel is possible, then life, or even the archeological remains of it, should have been detected. Right?
This is the Fermi Paradox.
Our galaxy is about 13.6 billion years old. In the beginning, conditions in our solar system would have been too chaotic for life to develop. Everything was getting hit by rocks and debris. It was truly hell. But once the bombardment calmed, the first microbes appeared within a few hundred million years.
Geologically speak, that is pretty fast.
Earth didn’t have much oxygen at the time, but the first lifeforms didn’t use it. They relied on arsenic. When cyanobacteria evolved about a billion years later (which is the blue-green sludge you find in water) it photosynthesized water and sunlight, and released oxygen.
MAGIC.
This began what’s called the Great Oxidation Event. It took a few hundred million years to build up enough oxygen in the atmosphere for life to breathe, but once it did, multi-celled organisms could evolve. And around a billion years after that, we have animals.
We also breathe oxygen, which just so happens to be the third most common element in the universe. Even water (a molecule, to be fair, not an element) is easy enough to find. It's on Enceladus, Europa, Titan, Mars and many other places.
The takeaway here is that life doesn’t need much. The ingredients are relatively abundant.
But to get complex life with brains and a consciousness that is self-aware, requires an entirely different set of circumstances. Think about it this way: there have been millions of different species on Earth, and yet only one of us has been able to build a space program.
In a universe with plenty of time, surely someone somewhere had a stable enough environment to develop a brain?
The Dark Forest is conjecture where there is other intelligent life in the universe, but they’re hiding out of fear of mutual destruction. The term came from a science fiction book written in 2008 by Chinese author Cixin Liu. You might recognize it as the sequel to The Three Body Problem, a popular Netflix series.
Even if a species isn’t as violent or all-consuming as we are, they would still have at least started out on a planet (or moon) that had ‘x’ number of resources, because planets are isolated by space. Unless a comet or asteroid is dropping off something new, the planet only has what it started with.
A species might be able to acquire more resources by synthesizing or extracting them from other planets later, but at some point, competition was likely a factor.
Cooperation, not competition, is a sign of advancement. And we're not as bad as you think at It.
Cooperation is what allowed our species to thrive. We have civilization because, for the most part, we have agreed on rules and order, and we do resolve our problems far more often than we drop a bomb on them.
An advanced civilization would have had to discover cooperation in order to develop, design, and construct anything capable of interstellar travel.
There are many theories as to why we haven’t seen signs of life. Maybe they’re so advanced that they couldn’t be bothered by us – like an ant colony on the other side of the planet that you and I are never going to visit. They just don’t find us that interesting.
Or maybe there were once countless civilizations in the universe, and humans are at the tail end of what was once a golden age of intelligent life in the universe.
As Arthur C. Clarke said, “Two possibilities exist: either we are alone in the universe or we are not. Both are equally terrifying.”