Stephen Hawking, the British theoretical physicist who found a link between gravity and quantum theory, and who declared that black holes aren't really black at all, has died, a spokesperson for the family told the Guardian and the Associated Press.
“He was a great scientist and an extraordinary man whose work and legacy will live on for many years," Hawking's children Lucy, Robert, and Tim said in a statement. "His courage and persistence with his brilliance and humor inspired people across the world.
“He once said: ‘It would not be much of a universe if it wasn’t home to the people you love.’ We will miss him for ever.”
Hawking was 76 years old, more than 50 years older than the age doctors told him he could expect to reach after being diagnosed in 1963 with amyotrophic lateral sclerosis (ALS), also called Lou Gehrig's disease.
"Few, if any, have done more to deepen our knowledge of gravity, space, and time," said British astrophysicist Martin Rees. In a reminiscence to mark the occasion of his Cambridge University colleague's improbable 70th birthday, he recalled a young man who was unsteady on his feet and spoke with great difficulty. No one expected him to live long enough to earn his Ph.D.
Although his degenerative disease progressively crippled him and robbed him of speech, Hawking did more than survive. He became "arguably the most famous scientist in the world," Rees said, "acclaimed for his brilliant research, for his best-selling books [about space, time, and the cosmos], and, above all, for his astonishing triumph over adversity."
Hawking's scientific claim to fame was his revelation that the universe began in a singularity, an infinitely dense point of space-time. Working with mathematical physicist Roger Penrose, he would show that Einstein's General Theory of Relativity "implied space and time would have a beginning in the big bang and an end in black holes," according to Hawking's website, and that "the way the universe began was completely determined by the laws of science."
In the early 1970s, he was the first to show that radiation escapes from black holes and that the holes aren't completely black. His theory explaining what came to be called Hawking radiation made him a scientific superstar.
It was, said Declan Fahy, a communications professor who studies scientists as celebrities and public intellectuals, "a signature contribution to cosmology [just] as the field became the most exciting place in physics."
Years later, Hawking would say that black holes do not have "event horizons," or points of no return, and that one of space's most mysterious objects may need rethinking. (See "No Black Holes Exist, Says Stephen Hawking—At Least Not Like We Think.")
Stephen William Hawking was born in Oxford, England, on January 8, 1942, a date that he often noted was exactly 300 years after the death of Galileo. The first of four children of Oxford University graduates Isobel and Frank Hawking, he grew up in a prodigiously intellectual family that read books at the dinner table and that he later described as "slightly eccentric."
His father, a noted researcher on tropical diseases, wanted his son to go into medicine; young Hawking was drawn to the stars. Hawking attended St. Alban's School and Oxford, where he studied cosmology and fought off boredom before graduating with honors.
He went on to Cambridge for his doctorate, earning it in 1966, three years after receiving the devastating diagnosis of ALS at age 21 and being given two and a half years to live.
The scientist would credit his relationship with Jane Wilde, whom he met shortly before his diagnosis, with giving him a reason to live. The couple married in 1965 and had three children, who survive him.
But the strain of being her husband's caregiver even as he became a worldwide phenomenon took a toll, and they divorced after 25 years of marriage. Hawking soon married one of his nurses, Elaine Mason. That marriage, tainted by allegations (later dismissed by police) that his second wife was abusive, also ended in divorce.
Hawking became an international celebrity in 1988 when his book, A Brief History of Time, was published. A layman's guide to the universe that explains complex mathematics and concepts in terms non-scientists can understand, it sold more than ten million copies and made him a household name.
In the years that followed, Steven Spielberg produced the film version while its author appeared in a string of films and TV shows, including a six-part series, Stephen Hawking's Universe. He played a hologram of himself on Star Trek: The Next Generation and an animated character in the Simpsons.
Hawking's franchise wasn't based solely on his work, though he'd already been elected at age 32 to Britain's prestigious Royal Society. "Because of his physical appearance," Fahy said, "he became a symbol of pure intellect, an image journalists recycled over and over again. That image connected with people around the world."
It also dismayed many of Hawking's fellow physicists, who considered comparisons to Einstein to be "over the top."
He was "a symbol of the overcoming of great difficulty, and that, obviously, you have to admire," said Virginia Trimble, an astronomer at the University of California, Irvine, who was a fellow student at Cambridge. "But I think the work would not have raised him as high in the pantheon if he'd done it as someone who could go out skiing every weekend."
Hawking himself acknowledged that he "fit the stereotype of a disabled genius," though he never let his wheelchair slow him down. He traveled the world giving lectures, always accompanied by a retinue of caregivers. At Cambridge, he held the Lucasian Professorship of Mathematics, Isaac Newton's former chair, and was director of research at the university's Center for Theoretical Cosmology.
In later years, Hawking completely lost his ability to speak after a bout of pneumonia necessitated a tracheotomy. Communicating took longer and longer. Toward the end, he could form just one word per minute using a speech-generating device controlled by his right cheek muscle. Fears that Hawking's brilliance would soon be "locked in" his body prompted efforts to find ways to preserve his ability to express himself.
Before his final decline, Hawking wrote on his website about the voice synthesizer that kept him connected to the world.
"It is the best I have heard," he wrote, "although it gives me an accent that has been described variously as Scandinavian, American or Scottish."