His Numbers Say We Are Not Alone

His Numbers Say We Are Not Alone

Monday, January 4, 1999

By DIEDTRA HENDERSON
Special from The Seattle Times

Don't expect too much romance from a statistician like Amir Aczel, a man whose career is rooted in the cool certainty of numbers.

Once Aczel had established, using probability theory, that there's a 100-percent chance that intelligent life exists elsewhere in the universe, the brief romance of the moment evaporated.

Rationality reared its familiar head.

"My next question was, 'Well, what do you do with that?' " said Aczel, an associate professor of statistics and mathematics at Bentley College in Massachusetts. "You can't talk to them. You can't meet them. It will take thousands of years to get a message across -- if they're even listening. It was more of a concept, rather than something practical."

That's the difference between Aczel, son of a cargo-boat captain who routinely navigated beneath the stars, and the late Carl Sagan, who often wondered which stars might provide warmth and produce the chemical building blocks necessary for life to thrive.

Sagan originally approached the publisher with the idea that turned into Aczel's newest book, "Probability 1: Why There Must be Intelligent Life in the Universe" (Harcourt Brace, $22). Sagan, author of "Contact" and co-founder of a society devoted to the search for extraterrestrial life, didn't get a chance to write the book before his death.

"If I had to guess," Sagan did write in "Pale Blue Dot: A Vision of the Human Future in Space," ". . . I would guess that the Universe is filled with beings far more intelligent, far more advanced than we are. But of course I might be wrong. Such a conclusion is at best based on a plausibility argument, derived from the numbers of the planets, the ubiquity of organic matter, the immense time scales available for evolution, and so on."

Or, as Aczel says via mathematical equation, probability, expressed by an upper-case P, is one, meaning there's a 100-percent chance that intelligent life exists elsewhere.

His mathematical equation takes into account the number of planets that contain life and are in orbit around at least one star in the known universe. (So far, Earth is the only planet to fit the criteria.)

It also factors in the extremely remote chance that DNA has developed and continues to thrive elsewhere and quantifies planets that orbit a nurturing star that is neither too hot nor too frigid.

To some, the notion that intelligent life exists elsewhere, in some galaxy so far away it's beyond the reach of our telescopes, is the stuff of science fiction. Physicist Enrico Fermi's skeptical question -- "Where are they?" -- still stands, 47 years after Fermi uttered it and despite 22 years of eavesdropping using the world's most sophisticated radio telescopes to listen for the signals generated by beings light years away.

Aczel, who also wrote "Fermat's Last Theorem," began his foray into the realm of outer space while walking around Orlando, Fla. He saw a sign for Harcourt Brace and wandered in, explaining to the book publisher that he was an author in need of an editor.

An executive editor who phoned back liked none of his book ideas. But she wondered whether he would write about the probability of extraterrestrial life.

"My initial reaction was, 'No, I don't want to do that.' I never really thought about that. I'm a statistician -- we believe in data. How am I going to prove that? How am I even going to consider such a possibility?" he recalled. "She said, 'Why don't you try?' "

A question that had never before occurred to him -- What else exists in space? -- now haunts him, the search for its answer occupying five or six hours of his day. "We were put on this planet to solve this puzzle of what is out there. It's a fascinating puzzle," he said.