If intelligent life is so likely to exist elsewhere in the universe, why haven’t we found it? Well, the chances of us coming across extraterrestrials are not looking good, according to a new study.
Scientists from the Future of Humanity Institute at Oxford University have revealed that we are probably the only advanced civilization out there, although they can’t say for sure. The team came to their conclusion after realizing that Fermi’s paradox and its supporting theories are somewhat flawed. The paradox is the conflict between the probability that intelligent life exists elsewhere in the universe and the lack of evidence of such.
This is linked to other theories like the Drake equation, which says that even if the probability of life elsewhere is small, because of the vast size of the universe, it is possible that there are a large number of civilizations somewhere out there.
The Oxford researchers took another look at the Drake equation and found how misleading guesswork can be when selecting the parameters to plug into the equation. Their findings are published in a new study, ‘Dissolving the Fermi Paradox.’
“When people discuss the [Drake] equation it is not uncommon to hear them say something like: ‘this parameter is uncertain, but let’s make a guess and remember that it is a guess,’ finally reaching a result that they admit is based on guesses,” Dr. Anders Sandberg, one of the study’s authors, told Universe Today.
“This often leads to overconfidence, and worse, the Drake equation is very sensitive to bias: if you are hopeful a small nudge upwards in several uncertain estimates will give a hopeful result, and if you are a pessimist you can easily get a low result.”
The researchers assigned each of the equation’s parameters a range from the smallest to the largest values they could possibly have, based on current knowledge. This revealed that in a third of the cases, the galaxy would be absolutely devoid of intelligent life anywhere else but Earth. In other scenarios, however, there could be a large number of civilizations.
It’s not all bad news, as the scientists’ conclusions don’t rule out alien life entirely. It just means that it’s more likely that humans are the only intelligent species in our galaxy at this moment - but that can all change in the future.
“What we are not showing is that SETI [search for extraterrestrial intelligence] is pointless – quite the opposite!” Sandberg said.