The master of black holes

The most famous scientist since Albert Einstein died on March 14, Einstein’s birthday. Stephen Hawking, the physicist and best-selling author, was 76.

Like Einstein, his trailblazing work in physics redefined the universe we live in, and continues to drive leading-edge scientific research even today. And like Einstein, Hawking was a global cultural hero: the scientist as authority, oracle, explainer in chief.

Unlike Einstein, Hawking was confined to a specially outfitted wheelchair since his early 30s; he was diagnosed with amyotrophic lateral sclerosis, a progressive neuromuscular disease, when he was 21, in 1963. For most of his life, he had physical control only of a finger, a muscle on his cheek, and his eyes. But his intellect remained undimmed. With the help of his partners and caregivers, he was able to communicate with the world at large, his synthesized voice (with its American accent, which the British citizen kept apologizing for) becoming as familiar as his trademark sense of humor. And partly by forcing himself to think of research problems in theoretical physics in new, nonverbal ways, he was able to continue doing pioneering work.

Millions around the world will remember him, first, for his personal story: the triumph over great adversity, the soaring example of mind overcoming the limits of the human body, the tale of a powerful, determined will surmounting innumerable inconveniences and daily humiliations to finally take flight. There is a famous picture of him floating on board a zero-gravity flight conducted by the US National Aeronautics and Space Administration some time after he turned 65, a smile lighting his face. Why, despite his condition, did he pursue adventure, travel frequently (he even made it to Antarctica), constantly push himself? he was asked. “I want to show that people need not be limited by physical handicaps as long as they are not disabled in spirit,” he replied.

Many will also remember Hawking as author: His “A Brief History of Time: From the Big Bang to Black Holes,” published in 1988, became widely, and wildly, popular. It was a dense book of some 100 pages, written for nonphysicists, and distributed not only in bookstores but also in drugstores and supermarkets. Hawking’s editor traces the remarkable trajectory of the book: “‘A Brief History of Time’ sold out its first US printing in a matter of days, became a No. 1 bestseller around the world, was translated into more than 35 languages, and went on to sell more than 10 million copies.” This attempt to tell the story of the quest for a grand unified theory, a theory of everything that unites both gravity and quantum mechanics, continues to sell well today.

Many will remember him as the subject of many a cultural moment: He has appeared in “The Simpsons,” the “Star Trek” series, “The Big Bang Theory,” a Pink Floyd song and, most movingly, in the movie “The Theory of Everything,” where the actor Eddie Redmayne won an Oscar for portraying him. (The movie was based not on “A Brief History of Time,” but largely on the memoirs of Jane Wilde, his first wife.)

It seems likely, though, that in the future millions more will remember him for his discoveries—his radical, revolutionary, reality-shaping ideas. We owe much of what we currently know about black holes, those mysterious gravitational traps that litter the universe like uncovered potholes, to Hawking’s brilliant theorizing and thought experiments.

The science writer Dennis Overbye sums up what may be Hawking’s most significant discovery, achieved when he applied quantum theory to black holes: “In a long and daunting calculation, Dr. Hawking discovered to his befuddlement that black holes—those mythological avatars of cosmic doom—were not really black at all. In fact, he found, they would eventually fizzle, leaking radiation and particles, and finally explode and disappear over the eons.” Amanda Gefter writes: “It’s no exaggeration to say that Hawking’s discovery has driven, and continues to drive, theoretical physics forward for the last four decades. It’s because the three great pillars of physics—general relativity, quantum mechanics and thermodynamics—all collide in his brilliant calculation, pointing the way toward some deeper unified theory.”

At the risk of oversimplifying, we can say that a black hole “glows”—How fitting that this has come to be known as Hawking radiation.