The visionary physicist who brought cosmology to the masses

In 1963, Stephen Hawking was told that he had two years to live. The 21-year-old cosmology student at the University of Cambridge had been diagnosed with amyotrophic lateral sclerosis, a neuromuscular wasting disease also known as Lou Gehrig’s disease. The condition would eventually rob him of his voice and control over almost his entire body, except for a muscle in his right cheek, which he would twitch to operate his speech-generation computer. Yet his ALS developed far more slowly than predicted. Over the next 55 years, Hawking would become one the world’s leading cosmologists, a pioneering thinker on black holes—objects so massive that not even light can escape their gravity—and a star among theoretical physicists. But it was his skill and wit in translating complex concepts into ordinary language that made him a global celebrity. “My goal is simple,” he once said. “It is complete understanding of the universe, why it is as it is and why it exists at all.”

Hawking was born in Oxford on Jan. 8, 1942, “the 300th anniversary of Galileo’s death, he liked to point out,” said The Washington Post. The son of a research biologist father and a Liberal Party activist mother, he was a mediocre student, “despite an obvious streak of brilliance that prompted his friends to nickname him ‘Einstein.’” At Oxford University, he found his physics studies so easy that he worked only an hour a day, giving him plenty of time to carouse with fellow boat club members. He graduated with the highest possible honors and went to Cambridge to pursue a cosmology Ph.D. Not long into his studies, Hawking noticed that his movements were becoming “clumsy and awkward,” said the Los Angeles Times. Diagnosed with ALS, he plunged into depression and skipped his doctoral work, occupying himself by “drinking, listening to Wagner records, and reading science fiction.” But his black mood lifted as the progression of his disease slowed unexpectedly. In 1965, he married Jane Wilde, a linguistics student, giving him another reason to live. “[I] started working hard for the first time in my life,” Hawking said. “To my surprise, I found that I liked it.” “While he declined physically, his body of work increased,” said The Times (U.K.). Unable to write out long strings of equations, Hawking attacked problems geometrically through pictures and diagrams. Using this technique, he reached a profound realization on black holes: “They could shine.” Hawking found that black holes leak thermal radiation from subatomic processes at their edges—emanations now known as Hawking radiation—and can potentially evaporate over eons. The discovery moved science one step closer toward a “theory of everything” that could reconcile newer theories of quantum physics—the study of the strange behavior of the smallest particles in the universe—with Albert Einstein’s theory of general relativity, essential for understanding the gravity of black holes. “But it was A Brief History of Time that rocketed Hawking to stardom,” said The Guardian. A popular-science account of fundamental physics and the birth of the universe, the 1988 book would sell more than 11 million copies and make him a global celebrity.

With the aid of a voice synthesizer—controlled first by his fingers and finally by his cheek—the wheelchair-bound Hawking gave speeches around the world, expounding on everything from space exploration to the dangers of artificial intelligence. The public, said The New York Times, came to regard him as “a rolling Delphic Oracle.” Hawking refused to be constrained by his disability or notions of how a public intellectual should behave. He appeared on Star Trek: The Next Generation and The Simpsons, and in 2007 took part in a zero-gravity flight aboard a specially equipped Boeing 727 that allowed him to float through the cabin as if he were in space. Hawking never stopped working: his final paper, on how mankind might detect parallel universes, was submitted two weeks before his death. Through it all he maintained his cosmic perspective, telling interviewers that he didn’t fear death, having grappled with the mysteries of the cosmos. “They’re named black holes because they are related to human fears of being destroyed or gobbled up,” said Hawking. “I don’t have fears of being thrown into them. I understand them. I feel in a sense that I am their master.”