The Fermi Paradox
The account
If the universe has billions of Earth-like planets, why hasn't anyone shown up? Maybe they already have.
What investigators found
The question "where is everybody?", asked by the physicist Enrico Fermi, remains open. The Drake Equation, from 1961, tries to estimate how many civilizations might exist in the galaxy.
The story
In 1950, at the Los Alamos laboratory in the United States, the physicist Enrico Fermi was having lunch with colleagues and chatting about flying saucers. In the middle of the conversation, he asked a question that would echo for decades: "Where is everybody?"
The logic is simple. Our galaxy has hundreds of billions of stars, many older than the Sun, and we already know of thousands of planets outside the Solar System. If even a small fraction of them harbored intelligent life, someone should have shown up by now or left some sign. In 1961, the astronomer Frank Drake created an equation to try to estimate how many civilizations might exist.
The possible answers range from "complex life is extremely rare" to "they exist, but avoid contact." For many ufologists, the paradox does not even exist, since the visitors would already be here. To this day, science has not found any confirmed evidence of life beyond Earth. Fermi's question is still hanging in the air.