Roaming the Cosmos

By Leon Jaroff/Cambridge

Darkness has fallen on Cambridge, England, and on a damp and chilly evening King's Parade is filled with students and faculty. Then, down the crowded thoroughfare comes the University of Cambridge's most distinctive vehicle, bearing its most distinguished citizen. In the motorized wheelchair, boyish face dimly illuminated by a glowing computer screen attached to the left armrest, is Stephen William Hawking, 46, one of the world's greatest theoretical physicists. As he skillfully maneuvers through the crowd, motorists slow down, some honking their horns in greeting. People wave. "Hi, Stephen," they shout.

A huge smile lights up Hawking's bespectacled face, but he cannot wave or shout back. Since his early 20s, he has suffered from amyotrophic lateral sclerosis (ALS), or "Lou Gehrig's disease," a progressive deterioration of the central nervous system that usually causes death within three or four years. Hawking's illness has advanced more slowly, and now seems almost to have stabilized. Still, it has robbed him of virtually all movement. He has no control over most of his muscles, cannot dress or eat by himself and needs round-the-clock nursing care.

A few years ago, Hawking's voice had deteriorated to a labored moan that only his family and a few associates could understand; one of them always stood close by to interpret his words. Then, in 1985, after Hawking nearly suffocated during a bout with pneumonia, he was given a tracheostomy that enabled him to breathe through an opening in his throat and a tube inserted into his trachea. The operation saved his life but silenced his voice. Now he "speaks" only by using the slight voluntary movement left in his hands and fingers to operate his wheelchair's built-in computer and voice synthesizer.

While ALS has made Hawking a virtual prisoner in his own body, it has left his courage and humor intact, his intellect free to roam. And roam it does, from the infinitesimal to the infinite, from the subatomic realm to the far reaches of the universe. In the course of these mental expeditions, Hawking has conceived startling new theories about black holes and the tumultuous events that immediately followed the Big Bang from which the universe sprang. More recently, he has unsettled both physicists and theologians by suggesting that the universe has no boundaries, was not created and will not be destroyed.

Most of Stephen Hawking's innovative thinking occurs at Cambridge, where he is Lucasian professor of mathematics, a seat once occupied by Isaac Newton. There, in the Department of Applied Mathematics and Theoretical Physics, he benevolently reigns over the relativity group, 15 overachieving graduate students from nine countries. On his office door is a small plaque irreverently reading QUIET, PLEASE. THE BOSS IS ASLEEP.

Hardly. From midmorning until he departs for dinner around 7 p.m., Hawking follows a routine that would tax the most able-bodied. When he rolled into the department's common room one morning last month, his students were sprawled in lounge chairs around low tables, talking shop. Maneuvering to one of the tables, Hawking clicked his control switch, evoking tiny beeps from his computer and selecting words from lists displayed on his screen. These words, assembled in sequence at the bottom of the screen, finally issued from the voice synthesizer: "Good morning. Can I have coffee?" Then, for the benefit of a visitor: "I am sorry about my American accent." (The synthesizer is produced by a California company.)

Fetching coffee, the nurse placed a bib on Stephen, who has difficulty swallowing, gently held his head forward and poured the beverage, a sip at a time, into his mouth. Meanwhile, Hawking was responding to a question from a student who knelt to read the answer as it slowly took shape on the dim liquid-crystal screen. The conversation shifted to creativity and how mathematicians seem to reach a creative peak in their early 20s. Hawking's computer beeped. "I'm over the hill," he said, to a chorus of laughter.

Most of Hawking's working day is spent in his cluttered, book-lined office, amid photographs of his wife Jane and their three children, Robert, 20, Lucy, 17, and Timmy, 8. There Stephen painstakingly writes technical papers or speeches on a desktop computer, stopping frequently to consult with his assistant, Graduate Student Raymond Laflamme, 27, who sits at his side. Occasionally, the artificial voice says "Lift," and Laflamme hoists up Hawking, who has slumped down in his chair. The word "glasses" signals that his spectacles have slid too far down his nose and must be pushed back.

Hawking was born on Jan. 8, 1942 -- 300 years to the day, he often notes, after the death of Galileo -- to parents who were Oxford graduates. As a small boy, he was slow to learn to read but liked to take things apart -- a way of "finding out how the world around me worked." But he confesses that he was never very good at putting things back together. When he was twelve, he recalls wryly, "one of my friends bet another friend a bag of sweets that I would never come to anything. I don't know if this bet was ever settled and, if so, who won."

Enthralled by physics, Stephen concentrated in the subject at Oxford's University College, but did not distinguish himself. He partied, served as coxswain for the second-string crew and studied only an hour or so a day. Moving on to Cambridge for graduate work in relativity, he found the going rough, partly because of some puzzling physical problems; he stumbled frequently and seemed to be getting clumsy.

Doctors soon gave him the bad news: he had ALS, it would only get worse, and there was no cure. Hawking was devastated. Before long, he needed a cane to walk, was drinking heavily and ignoring his studies. "There didn't seem to be much point in completing my Ph.D.," he says.

Then Hawking's luck turned. The progress of the disease slowed, and Einsteinian space-time suddenly seemed less formidable. But what really made the difference, he says, "was that I got engaged to Jane," who was studying modern languages at Cambridge. "This gave me something to live for." As he explains, "If we were to get married, I had to get a job. And to get a job, I had to finish my Ph.D. I started working hard for the first time in my life. To my surprise, I found I liked it."

What particularly intrigued Stephen was singularities, strange beasts predicted by general relativity. Einstein's equations indicated that when a star several times larger than the sun exhausts its nuclear fuel and collapses, its matter crushes together at its center with such force that it forms a singularity, an infinitely dense point with no dimensions and irresistible gravity. A voluminous region surrounding the singularity becomes a "black hole," from which -- because of that immense gravity -- nothing, not even light, can escape.

Scientists years ago found compelling evidence that black holes exist, but they were uncomfortable with singularities, because all scientific laws break down at these points. Most physicists believed that in the real universe the object at the heart of a black hole would be small (but not dimensionless) and extremely dense (but not infinitely so). Enter Hawking. While still a graduate student, he and Mathematician Roger Penrose developed new techniques proving mathematically that if general relativity is correct down to the smallest scale, singularities must exist. Hawking went on to demonstrate -- again, if general relativity is correct -- that the entire universe must have sprung from a singularity. As he wrote in his 1966 Ph.D. thesis, "There is a singularity in our past."

Stephen later discerned several new characteristics of black holes and demonstrated that the stupendous forces of the Big Bang would have created mini-black holes, each with a mass about that of a terrestrial mountain, but no larger than the subatomic proton. Then, applying the quantum theory (which accurately describes the random, uncertain subatomic world) instead of general relativity (which, it turns out, falters in that tiny realm), Hawking was startled to find that the mini-black holes must emit particles and radiation. Even more remarkable, the little holes would gradually evaporate and, 10 billion years or so after their creation, explode with the energy of millions of H-bombs.

Other physicists, long wedded to the notion that nothing can escape from a black hole, have generally come to accept that discovery. And the stuff emitted from little black holes (and big ones too, but far more slowly) is now called Hawking radiation. "In general relativity and early cosmology, Hawking is the hero," says Rocky Kolb, a physicist at Fermilab in Illinois. Caltech Physicist Kip Thorne agrees: "I would rank him, besides Einstein, as the best in our field." And what if a mini-black hole explosion is finally observed? "I would get the Nobel Prize," says Stephen, matter-of-factly.

Hawking's ability to perceive complex truths without doodling long equations on paper astounds his colleagues. "He has an ability to visualize four- dimensional geometry that is almost unique," says Werner Israel, a University of Alberta physicist who has collaborated with Hawking in relating mini-black holes to the new cosmic-string theories. Observes Kolb: "It's like Michael Jordan playing basketball. No one can tell Jordan what moves to make. It's intuition. It's feeling. Hawking has a remarkable amount of intuition."

Now, hoping to fulfill a career-long dream of seeing his books at airport newsstands, Stephen is putting the finishing touches on A Brief History of Time (Bantam), a popular nonmathematical account that will be published in April. "Someone told me that each equation I included in the book would halve the sales," says Hawking. "In the end, however, I did put in Einstein's famous equation E = m c squared. I hope that this will not scare off half my potential readers."

Hawking has visited the U.S. 30 times, made seven trips to Moscow, taken a round-the-world jaunt, and piloted his wheelchair on the Great Wall of China. All this despite daunting logistical problems. "Our party usually consists of Stephen, me, three nurses and sometimes Jane," says Laflamme. "I usually try to arrange group fares." On the road, the activities occasionally deviate somewhat from physics. One night Stephen accompanied a group to a Chicago discotheque, where he joined in the festivities by wheeling onto the dance floor and spinning his chair in circles. Later, in a restaurant, a waiter passed the cork from a newly opened bottle of wine under Stephen's nose. The computer beeped, and the voice proclaimed, "Very good." Hawking was just being polite; the tracheostomy also deprived him of his sense of smell. Says Indian-born Amarjit Chohan, one of Stephen's nurses: "There is an aura around him, a spiritual atmosphere. He is going to end up as a saint."

Meanwhile, Hawking is pursuing a more earthly reward, seeking what Cambridge Astronomer Martin Rees calls the physicists' Holy Grail: a theory that will combine general relativity with the quantum theory. This requires "quantizing" gravity, the only one of nature's four basic forces that cannot yet be explained by the quantum theory.

In the course of that search, Hawking, who has no qualms about recanting his own work if he decides he was wrong, may have transcended his famous proof that singularities exist. With Physicist James Hartle, he has derived a quantum wave describing a self-contained universe that, like the earth's surface, has no edge or boundary. If that is the case, says Hawking, Einstein's general theory of relativity would have to be modified, and there would be no singularities. "The universe would not be created, not be destroyed; it would simply be," he concludes, adding provocatively, "What place, then, for a Creator?"

Indeed, the universe is never far from Stephen's thoughts. Nurse Chohan recalls the day that Hawking's children talked him into a few hands of casino, a card game Stephen had not played since his own childhood. Asked how he could remember the rules, Hawking did not hesitate. It is simple, he responded, "because I play the game of universe."