Throughout his public years, Einstein embodied contradictions. A pacifist, he would advocate the construction of the atomic bomb. He argued for a world without borders, and campaigned for the establishment of the state of Israel—so much so that in 1952 he was invited to be its president. He was a genius, puttering absent-mindedly around his house in Princeton, and he was a joker, sticking out his tongue for a photographer. But it wasn’t simply these contradictions that distinguished him. It was their scale. They were all larger than life, and so therefore, the thinking went, must he be, too.
But he wasn’t, as he well knew. His first marriage had ended in divorce, a second, to a cousin, in her death, nearly two decades before his. He fathered one illegitimate daughter, who is thought to have been given up for adoption and is lost to history, and two sons, Hans Albert and Eduard. One of them, Eduard, suffered from schizophrenia. Hans Albert taught engineering at UC Berkeley. Yet somehow Einstein père became a myth among men.
It was a fate Einstein hated. “I feel,” he wrote a friend in 1920, “like a graven image”—as if there were something blasphemous in how his idolaters even then were beginning to fashion him. And maybe there was. Once the Nazis were defeated, Einstein would become not all things to all people but one thing to all people: a saint.
The halo of white hair helped. In 1919, when the world first made Einstein’s acquaintance, his 40-year-old, slightly cocky visage only hinted at the caricature to come. But in time his hair flew, like a mind untethered, while the bags under his eyes deepened, as if from the burden of looking too hard and seeing too much. And as for those eyes—well, when Steven Spielberg was designing the title character of E.T. the Extra-Terrestrial, and he wanted his alien ambassador of good will to have eyes that were moist like a wise old man’s yet twinkling with childlike wonder, he knew whose to use.
Long before the public beatified Einstein, his fellow physicists had begun to question his infallibility. When the Russian mathematician Aleksandr Friedmann in 1922 noted that, according to his calculations using Einstein’s equations, the universe could be expanding or contracting, Einstein wrote a brief rebuttal saying Friedmann’s math was mistaken. Ayear later Einstein acknowledged that the error had in fact been his, yet he remained unrepentant. Only after the American astronomer Edwin Hubble’s 1929 discovery that other galaxies are receding from our own—that the universe is indeed expanding—did Einstein relent. He’d committed his “greatest blunder,” he sighed.
Stubbornness would also dominate his attitude toward quantum mechanics, even though the field was partly an outgrowth of Einstein’s 1905 paper on photons. Einstein frequently and famously objected to the central tenet of quantum theory—that the subatomic world operates according to statistical probabilities rather than cause-and-effect certainties. “God does not play dice with the universe,” he often declared, and to the increasing exasperation of colleagues, he spent the last three decades of his life trying—without success—to find a grand unified theory that would banish such uncertainty.
“Einstein was single-minded, and you can see the good and the bad in that,” says Michael S. Turner, a cosmologist at the University of Chicago and a director for mathematical and physical sciences at the National Science Foundation. “He was single-minded in reconciling general relativity with Newton’s theory of gravity, and he hit a home run. But he was also single-minded about finding a unified field theory, and from 1920 on, his career was that of a mere mortal.” Over the decades, experiments have repeatedly supported both the relativistic and the quantum interpretations of the cosmos. “Space is flexible,” Turner says. “Time warps. And God plays dice.”
In the half century since his death, astronomers have validated perhaps the most revolutionary prediction embedded within Einstein’s equations—the big bang theory of the creation of the universe, a conclusion that seems inevitable if one “runs the film” of Hubble’s expanding universe backward. And there have been other startling ramifications of relativity theory, such as black holes, which can be created by collapsed stars with masses so great that their gravitational force swallows everything in their vicinity, including light. As Weart says, quoting a maxim among physicists, “The general theory of relativity just dropped in 50 years ahead of its time.”
Scientists are still asking questions that Einstein made possible: What powered the big bang? What happens to space, time and matter at the edge of a black hole? What mysterious energy is causing the acceleration of the universe’s expansion? “This is really the golden age for Einstein’s theory, quite apart from the centenary,” says Clifford M. Will, a physicist at WashingtonUniversity in St. Louis and the author of Was Einstein Right?
For his part, Einstein never quite knew what hit him. “I never understood why the theory of relativity with its concepts and problems so far removed from practical life should for so long have met with a lively, or indeed passionate, resonance among broad circles of the public,” he wrote in 1942, at age 63. “What could have produced this great and persistent psychological effect? I never yet heard a truly convincing answer to this question.”