The question of whether there are other forms of life in the universe has boggled the minds of scientists for time immemorial. And now, University of Rochester physics and astronomy professor Adam Frank has gone on record to say that there may be, or have been other civilizations in our universe, though it would be virtually impossible to communicate with them.
“The question of whether advanced civilizations exist elsewhere in the universe has always been vexed with
three large uncertainties in the Drake equation,” said Frank, referring to previous research from the early 1960s. In 1961, astronomer Frank Drake proposed his eponymous equation which, in brief, lists a number of conditions that would allow technological civilizations to communicate with Earthlings. That was an equation Frank and co-author Woodruff Sullivan of the University of Washington sought to update in their new study.
“We’ve known for a long time approximately how many stars exist,” Frank’s statement continued. “We didn’t know how many of those stars had planets that could potentially harbor life, how often life might evolve and lead to intelligent beings, and how long any civilizations might last before becoming extinct.”
According to Frank, there were still a lot of missing pieces of information when Drake developed his equation over 50 years ago. These included the number of stars that could host some form of life, the evolution progression of other life forms into intelligent creatures, and how long civilizations may exist.
The new A = Nast · fbt equation is based on Drake’s, but has some of the big unknowns eliminated. The “A” refers to the number of technological species that have formed in the universe’s observable history. Nast pertains to the “number of habitable planets in a given volume of the universe,” while fbt refers to the chances a technological species could come about in one of those habitable planets.
Based on the researchers’ findings, the odds that humans are the only intelligent form of life in the universe is one in 10 billion trillion. But the fact that there are such great distances between stars, plus the uncertainty of how long technological species can exist before extinction, means there’s a very, very good chance humans may never communicate with other civilizations in the universe.
“Our results imply that our evolution has not been unique and has probably happened many times before,” said Frank in conclusion. “The other cases are likely to include many energy-intensive civilizations dealing with their feedback onto their planets as their civilizations grow. That means we can begin exploring the problem using simulations to get a sense of what leads to long-lived civilizations and what doesn’t.”
