The Fermi Paradox asks why we haven't found any evidence of aliens. Here are 13 potential answers to that question.
- The Milky Way galaxy has billions of planets that could potentially host life. Yet despite scientists' efforts to monitor for and occasionally signal to extraterrestrials, we have not found any evidence that aliens exist.
- This conundrum is known as the Fermi Paradox, and it has inspired debate among researchers for decades.
- In his new book, "End Times," author Bryan Walsh discusses the many theories about why we have not made contact with aliens - and possibly why we never will.
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In the summer of 1950, physicist Enrico Fermi posed a simple question to his colleagues over lunch: "Where is everybody?"
Fermi was referring to alien life in the universe.Arguably, he said, in the 4.4 billion years it took for intelligent life to evolve on our planet, the rest of our galaxy should have been overrun with similarly smart, technologically advanced aliens. But despite decades of searching the Milky Way for signs of extraterrestrials, we haven't found anything or anyone.
This conundrum has come to be known as the Fermi Paradox.
Scientists have offered myriad potential answers to the question, including that aliens are hibernating or deliberating hiding from us. Some researchers have also suggested that highly advanced technological civilizations destroy themselves before they have the opportunity to get in contact with other intelligent life in the universe.