The Cosmic Code
Does the universe run on a simple computer program?
Perhaps the year's most unusual bestseller is A New Kind of Science, a doorstop of a book by physicist and erstwhile boy wonder Stephen Wolfram. With its publication in May, the author emerged from more than 10 years of near isolation from mainstream research to proclaim he's the first to glimpse how the universe really works. The theme of its 1,200-plus pages: The universe is in essence just a simple computer program. All of its complexity, up to and including ourselves, is the product of just a few, as-yet-unknown instructions--the equivalent of a few lines of code in a digital computer.
More than 150,000 copies of the book, published by Wolfram's own company and dubbed simply "ANKOS" in technophile Internet chat rooms, are in print. Wolfram's bold claims to all-encompassing answers have clearly struck a chord, at least in the public. But among scientists, who have now had time to ponder Wolfram's message, the reception has been more muted. One factor is pique, on the part of those who say Wolfram takes credit for insights that have been in circulation for years. Others are skeptical precisely because the revolution Wolfram is brashly proclaiming has been proclaimed before--yet caused barely a ripple in mainstream science.
If nothing else the book highlights how deeply digital computers, those potent icons of modern times, are embedded in contemporary thought. And as Dennis Danielson, a University of British Columbia English professor who specializes in the literature of cosmology, puts it, "We think with the language we speak."
Like clockwork. Some 2,600 years ago the discovery of the laws of proportion underlying musical tones inspired followers of Pythagoras to imagine a celestial "music of the spheres" governing the paths of planets, seasons, biological cycles, and other natural rhythms. Similarly, medieval European clockmakers so wowed Descartes, Kepler, Boyle, and other thinkers that they deemed the universe a mechanical clockwork. And now, when Wolfram says the universe is a program, he means literally, as in computer software.
Wolfram's track record as a genius guaranteed that his claim would draw attention. He gained a Ph.D. at age 20. A year later, in 1981, he was on the Caltech faculty and won a MacArthur "genius award." While at the University of Illinois he invented and still markets a powerful scientific programming language called Mathematica that has made him rich. And his notion is rooted in solid computer science: a widely studied kind of program called a cellular automaton, or CA for short.
A CA provides simple rules that govern how discrete cells on a fixed grid switch from one state to another--say, white to black--in response to changes in neighboring cells. In the world of cellular automatons, reality is not continuous but is a grainy mesh of local bits and bytes. Even time does not progress smoothly, but by ultratiny ticks of a cosmic clock.
Wolfram's book smacks readers' eyeballs with myriad, detailed images of CA-generated patterns, mostly resembling crazy checkerboards. They have played across his computer screen for more than 20 years. As he pondered them by the thousands, he tells U.S. News, he developed "an intuition" that a simple rule like those that produce the endlessly shifting patterns of some CAs must also have spawned the complexity of the universe, from atoms to galaxies and living organisms. The "new science" of his book's title would rely on such step-by-step programs to understand and mimic nature, rather than on the continuous equations of calculus and other advanced mathematics that scientists now use.