Stephen Hawking, the British physicist whose scientific achievements, decades-long battle with Lou Gehrig’s disease, and best-selling book “A Brief History of Time” helped make him the most celebrated scientist since Albert Einstein, died at his home in Cambridge, England, his family said in a statement early Wednesday. He was 76.
Dr. Hawking, who was emeritus Lucasian professor of mathematics at Cambridge University, a chair once held by Sir Isaac Newton, was often called the most brilliant theoretical physicist since Einstein. His most important work — which brought together quantum mechanics, thermodynamics, and the general theory of relativity — marked a startling extension of Einstein’s greatest discovery, relativity.
Dr. Hawking focused his research on what are now known as black holes, dying stars that have collapsed upon themselves, forming centers (“singularities”) of such density and with such immense gravitational force that nothing, not even light, can escape. In a 1965 paper, a colleague, Roger Penrose, had done the theoretical work to demonstrate that singularities could exist.
Dr. Hawking took this framework and applied it to the origins of the universe as a whole, treating the entire universe as if it were a singularity and showing that “time has a beginning.” His name then became linked with the Big Bang theory of the creation of the universe, and his work became a major support of the theory, which is now the generally held view on the origins of the cosmos.
Dr. Hawking’s groundbreaking advances in cosmology, the science of the nature of the universe, early on earned him renown among scientists. What made him a household name was his tragic illness. He was first diagnosed as having amyotrophic lateral sclerosis in 1962, just as he was beginning graduate studies.
ALS, more commonly known as Lou Gehrig’s disease, afflicts the spinal cord and those parts of the brain that control motor functions. As the affected cells degenerate, muscular atrophy leads to paralysis. However, other functions of the brain, such as memory and reasoning, remain unaffected.
Dr. Hawking’s doctors told him he had two years to live. He proved them spectacularly wrong. Demonstrating an indomitable, even heroic, will, Dr. Hawking carried on with his work and is believed to have been the longest-surviving patient to have ALS.
Almost immediately Dr. Hawking was required to use a cane, then crutches, and eventually a wheelchair. As he lost use of his arms, he was unable to work out equations on a blackboard. He was called upon to produce prodigious feats of memory to deal with the mathematics involved in theoretical physics. As Werner Israel, a colleague, once noted, Dr. Hawking’s “achievement is as though Mozart had composed and carried an entire symphony in his head.”
His arms and legs were not the only parts affected by the disease. By the mid 1970s, only family members and close associates could understand his increasingly slurred speech. Even that form of communication was denied him when a near-fatal bout with pneumonia in 1985 necessitated a tracheotomy, which left him voiceless. He could, however, laboriously type out words with his left hand — and, in fact, had for several years been using a computer keyboard to facilitate communication.
A computer-controlled voice synthesizer was then developed for Dr. Hawking, and it was by machine that he communicated for the rest of his life.
“It was a bit slow,” he once said with characteristic humor, “but then I think slowly, so it suited me well.” As his muscular control further deteriorated, eye twitches were eventually employed to control the synthesizer.
This remarkable medical history combined with Dr. Hawking’s scientific eminence to make him a worldwide celebrity. People magazine described him in 1995 as “almost a character of science fiction, a disembodied intellect above and beyond the flesh.”
That disembodied intellect was also one of the world’s best-selling authors. Since its publication in 1988, “A Brief History of Time,” Dr. Hawking’s introduction to cosmology for lay readers, has been translated into 40 languages and sold some 10 million copies. Presumably, he could have sold 20 million: Told by a publisher that “each equation I included in the book would halve the sales,” Dr. Hawking “resolved not to have any equations at all,” but did end up including Einstein’s E=mc2.
Dr. Hawking’s wizened, 90-pound frame, slumped in a computer-equipped wheelchair, became a familiar media image. The director Errol Morris made a film of “A Brief History of Time,” starring Dr. Hawking. When the publisher of his first book, an esoteric work titled “The Large Scale Structure of Space-time,” changed the author credit on its dustjacket from “S. W. Hawking” to “Stephen Hawking,” sales jumped. A character on the ABC series “Lost” was named “Hawking,” a nod to the scientist. He appeared on an episode of “Star Trek: The Next Generation”and was a “guest voice” on “The Simpsons.” “We were in awe of him, said Matt Selman, one of the show’s writers. “He was unbelievably cool.”
Dr. Hawking published four children’s books, written with his daughter, as well as the best-selling “The Universe in a Nutshell,” in 2001, and “The Grand Design,’ written with Leonard Mlodinow, in 2010, among other titles.
“I want my books sold on airport bookstalls,” Dr. Hawking once said.
Stephen William Hawking was born in Oxford, England, on Jan. 8, 1942 — the 300th anniversary of the death of Galileo Galilei, the father of modern science. Dr. Hawking dryly noted in his 2013 autobiography, “My Brief History,” that some 300,000 other babies were born the same day and “I don’t know whether any of them was later interested in astronomy.” He was the son of Isobel and Frank Hawking, a physician specializing in research into tropical diseases. “My father would have liked me to do medicine,” Dr. Hawking later recalled. “However, I felt that biology was too descriptive and not sufficiently fundamental.”
Although Dr. Hawking did not learn to read until he was 8, he did well enough in secondary school to win a scholarship to Oxford University. While there, he won the University Physics Prize yet later estimated that during his three years as an undergraduate he spent perhaps 1,000 hours actually studying — or roughly 60 minutes a day. Capitalizing on his small frame, he was coxswain on his college crew team. He also began to display the mischievousness that would mark him for the rest of his life. A favored tactic in later years when he heard an annoying statement was to run his wheelchair over the speaker’s toes. At Oxford, Dr. Hawking was, in the words of his biographers, Michael White and John Gribbin, “a graffiti-daubing sluggard.”
His sluggardness put Dr. Hawking on the cusp between a First- and Second-class degree. In such cases, an oral examination is prescribed. Asked by his chief examiner what his plans were, he replied, “If you award me a First, I will go to Cambridge” (a First was required for the program he had applied to there). “If I receive a Second, I shall stay at Oxford, so I expect you will give me a First.”
Dr. Hawking did go to Cambridge and began graduate work in cosmology. Earlier that year, he had begun to exhibit symptoms of his illness. “Lay off the beer” was the advice of the first doctor he consulted. Soon enough Dr. Hawking was diagnosed. The fact that he was in theoretical physics — a discipline consisting of mathematical calculations rather than experiments — meant that he could expect to continue working. In addition, as colleagues later noted, his illness might even be seen to have expedited his work, freeing him from the standard bureaucratic chores of academe and mundane domestic tasks.
That was little consolation to Dr. Hawking, and he entered into a state of depression, secluding himself and listening to music, particularly the operas of Richard Wagner. He found himself thinking: “How could something like this happen to me? Why should I be cut off like this?” Yet, as he later recounted, the memory of a boy dying of leukemia in the next hospital bed while Dr. Hawking was undergoing the tests that diagnosed ALS acted as a powerful corrective.
“Clearly there were people worse off than me. At least my condition didn’t make me feel sick. Whenever I feel inclined to be sorry for myself, I remember that boy.”
An even more important factor in bringing Dr. Hawking out of his depression was Jane Wilde. He had met her at a family New Year’s Eve party shortly before his disease was diagnosed. They married in 1965. As his disease worsened, she devoted herself to his care.
The early years of Dr. Hawking’s battle with the disease, along with this marriage, inspired the 2014 film “The Theory of Everything.” Eddie Redmayne won a best actor Academy Award for his portrayal of the scientist.
The couple later had three children: Robert, Lucy, and Timothy. Dr. Hawking once said that his greatest regret about his illness was “not being able to play physically with my children.”
The Hawkings divorced in 1995, and later that year he married Elaine Mason, who had been his nurse for a number of years before she and Dr. Hawking married and whose first husband had designed the voice synthesizer he employed. They divorced in 2007.
His three children released a statement to the British media early Wednesday, according to the Guardian newspaper: “He was a great scientist and an extraordinary man whose work and legacy will live on for many years.
“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.”
In 1965, Dr. Hawking received his PhD for his work on black holes, contained in his thesis, “Properties of Expanding Universes.” He was made a fellow of Cambridge’s Gonville and Caius College. It was an especially exciting time in cosmology, as such astronomical discoveries as pulsars and quasars opened new avenues for Dr. Hawking and his colleagues to pursue.
Over the next few years, he built a reputation for himself as a gifted — and somewhat brash — theoretician. He and Penrose worked further on singularities, predicting in 1970 that black holes could in fact be detected. This later was borne out experimentally. Then came what one writer has called “Hawking’s Eureka Moment,” a flash of insight that transformed cosmology. “One evening in November 1970,” he later recalled, “I started to think about black holes as I was getting into bed. My disability makes this rather a slow process, so I had plenty of time.” The realization came to him that the surface area of a black hole can remain constant or increase, but can never decrease.
Hawking’s Law of Area Increase, as this became known, raised numerous problems, however, problems that led to the formulation by Dr. Hawking of a breathtaking menage a trois among quantum mechanics and relativity (the two greatest achievements of 20th-century physics) and thermodynamics, a field of 19th-century physics. Dr. Hawking argued that, against all previous assumptions, “black holes are really not black after all. They have a temperature, an entropy and produce radiation just like any other thermodynamic body.”
“It is unlikely that there has ever been a more powerful demonstration of the self-consistency of physics,” the science writer J. P. McEvoy has written, “than this formulation, which became known as Hawking Radiation.”
In March 1974, shortly after the announcement of Hawking Radiation, he was made a fellow of the Royal Society. Dr. Hawking was 32, one of the youngest scientists to be invested in that august assemblage.
Seven years later, Dr. Hawking weighed in again on his first research interest, the origins of the universe. At a Vatican conference, he delivered his “No Boundary Proposal,” in which he applied quantum theory — which seeks to explain the transfer of energy among matter’s most basic building blocks — to the origins of the universe, arguing that space and time were finite but without boundary or edge. Dr. Hawking went on to use the No Boundary Proposal to develop quantum cosmology, further refining the application of quantum mechanics to the singularity at the Big Bang.
It was this turn in his work that led Dr. Hawking to write “A Brief History of Time.” Other books by him include “300 Years of Gravitation,” “Black Holes and Baby Universes” and, as joint editor, “General Relativity: An Einstein Centenary Survey,” “Superspace and Supergravity,” and “The Very Early Universe.”
When Dr. Hawking announced in 2004 that he’d made a mistake in his calculations about black holes, that information can in fact escape from them, it drew worldwide headlines.
“I’m sorry to disappoint science fiction fans,” he announced at a conference in Dublin that year, “but if information is preserved there is no possibility of using black holes to travel to other universes.” Provoking laughter from the audience he added, “If you jump into a black hole, your mass energy will be returned to our universe, but in a mangled form, which contains the information about what you were like, but in an unrecognizable state,”
Dr. Hawking made headlines in 2007 with a different form of travel. He took off from Cape Canaveral in a specially designed Boeing 727 and experienced zero gravity for eight 25-second periods.
“It was amazing,’ Dr. Hawking said of the experience of floating in air. “I could have gone on and on. Space, here I come.”
Dr. Hawking was the recipient of numerous honorary degrees and awards, among them the Wolf Foundation Prize, the Maxwell Medal, the Fundament Physics Prize, and Albert Einstein Award.
“If you understand how the universe operates,” he wrote in “My Brief History,” “you control it, in a way.”
Mark Feeney can be reached at firstname.lastname@example.org