PAGE PROOF Date ________ MW______ AuCx____ Copy ____ JT____ DG____ SLP____ MP____ AGE 64 Einstein’s Grand Quest for a Unified Theory He failed, of course, but he didn’t exactly waste his time stein was at the Institute for Advanced Study situation is the following. We are stand- in Princeton, New Jersey. Yet both men ing in front of a closed box which we can- were outsiders of a sort. In his later years, not open, and we try hard to discover about Einstein had become increasingly isolated what is and is not in it.” That closed box from the mainstream physics community, is the universe, of course, and no one had refusing to embrace the strange but pow- done more to pry off the lid than Einstein. erful theory of quantum mechanics—with Yet in the eyes of nearly all his colleagues its particles that are also waves and that he had contributed almost nothing of im- transform simply because they’re observed. portance to physics for almost 20 years. Nature, he argued, couldn’t be so perverse. Were they right? Did he squander his ge- So for nearly 30 years he had pursued what nius by chasing vainly after an ultimate the- most physicists considered a quixotic goal: ory? That is the conventional view. But at the creation of a unified field theory to de- least a few physicists now argue that Einstein scribe all the forces of nature. was far ahead of his time, raising questions URIED IN ALBERT EINSTEIN’S MAIL ONE SPRING That was the occasion for Moffat’s let- that will challenge researchers for decades. day in 1953 lay a letter from an ordinary ter. He thought he could offer Einstein “It’s often said that Einstein wasted his time mortal, a 20-year-old high-school dropout some constructive criticism.“I wrote him later in life,”Moffat, who went on to become Bnamed John Moffat. Two more disparate to say that I wasn’t happy about what he a theoretical physicist, says.“This of course correspondents would be hard to imagine. was doing,”Moffat recalls. There was noth- is erroneous. Einstein never wasted his time.” Moffat was an impoverished artist and self- ing unusual about this. Plenty of people Einstein and his colleagues, taught physicist. Einstein was a mythic fig- sent letters to Einstein, not all of them ra- EINSTEIN’S SPLIT WITH MAINSTREAM PHYSICS Valentine Bargman and Peter ure—the world’s most famous scientist. tional. But in Moffat’s case something un- came at the very height of his career. In 1927, Bergman, discuss physics at Moffat was living with his British father expected happened: Einstein wrote back. when he was 48, the world’s leading physi- Princeton in 1940. What most bothered Einstein about quantum and Danish mother in Copenhagen. Ein- “Dear Mr. Moffat,”the reply began.“Our cists gathered at a conference in Brussels to mechanics wasn’t that God plays dice, but that our own observations influence how the dice roll. 1 BY TIM FOLGER Informantion here about the writer of the story very accomplished authere ot eh aejrkleha ktheklajrkleaj 2 C M Y K C M Y K 110000 AGE 64 debate an issue that remains contentious to and they suggested a simple thought ex- thought experiment was meaningless: If lem. In 1919 the German mathematician HEN MOFFAT FIRST READ EINSTEIN’S him: Einstein was still openly skeptical of this day: What does quantum mechanics periment to explain why: Imagine that a the second particle was never directly mea- Theodor Kaluza and, later, the Swedish papers in 1953, he didn’t dis- quantum mechanics. “Finally, Bohr said have to say about reality? Einstein had won particle decays into two smaller particles sured, it was pointless to talk about its prop- physicist Oskar Klein had suggested a unique W miss them as professional that as far as he was concerned, Albert had the Nobel Prize in physics for research that of equal mass and that these two daughter erties before or after the first particle was way to join the two forces. Just as Einstein physicists did. But then Moffat was no become an alchemist,”Moffat remembers. showed that light consists of particles—re- particles fly apart in opposite directions. In measured. But it wasn’t until 1982, when had introduced a fourth dimension into physicist at the time. As an out-of-work In his search for a transcendent theory, Ein- search that helped lay the groundwork for order to conserve momentum, both parti- the French physicist Alain Aspect con- his equations of general relativity to de- 20-year-old in Copenhagen, he had be- stein had lost touch with the gritty, roll-up- quantum mechanics. Yet he dismissed the cles have to have identical speeds. If you structed a working experiment based on scribe gravity, Kaluza and Klein suggested come interested in cosmology while brows- your-sleeves world of experimentation. He new theory out of hand. At the conference, measure the velocity or position of one par- Einstein’s ideas, that Bohr’s argument was that a fifth dimension was needed to in- ing through the library in his spare time. was practicing metaphysics, not physics. he clashed with the great Danish physicist ticle, you will know the velocity or position vindicated. In 1935 Einstein was still con- corporate electromagnetism. To his surprise, he found that he could eas- “He thought Einstein was wasting his time,” Niels Bohr, launching a feud that would last of the other—and you will know it with- vinced that he had refuted quantum me- Einstein spent the last two decades of ily absorb the advanced mathematics and Moffat says.“And he told me I was wasting until Einstein’s death in 1955. out disturbing the second particle in any chanics. And from then until his death 20 his life refining this idea. At the same time, physics in popular science books and mag- my time with my interest in Einstein’s ideas.” Bohr championed the strange new in- way. The second particle, in other words, years later, he devoted nearly all his efforts he tried to iron out what he saw as prob- azines. He plowed through four years’ It didn’t end there. A local newspaper sights emerging from quantum mechan- went on to publish a story about Moffat’s ics. He believed that any single particle—be encounters with Einstein and Bohr, and it an electron, proton, or photon—never that story prompted the British consulate occupies a definite position unless some- in Copenhagen to contact the Department one measures it. Until you observe a par- “I have locked myself into quite hopeless of Scientific and Industrial Research in Lon- ticle, Bohr argued, it makes no sense to don. The department brought Moffat to ask where it is: It has no concrete reality; scientific problems,”Einstein wrote near London and paid his way to the Institute it exists only as a probability. the end of his life.“I have remained of Advanced Study in Dublin, for an inter- Einstein scoffed at this. He believed, em- view with Erwin Schrödinger. A polymath phatically, in a universe that exists com- estranged from the society here.” who spoke six languages, Schrödinger was pletely independent of human observation. most famous for the wave equation that All the strange properties of quantum the- now bears his name—an elegant mathe- ory are proof that the theory is flawed, he matical description of one of the central said. A better, more fundamental theory lems in his general theory of relativity. In worth of college-level material in about a mysteries of quantum theory: that all par- will eliminate such absurdities. “Do you cases where gravity was extremely strong, year, then he moved on to professional ticles can also behave like waves. really believe that the moon is not there his theories broke down. Moreover, they physics journals. “I got hold of some of Schrödinger was sick in bed with severe unless we are looking at it?” he asked. seemed to permit the formation of what Einstein’s papers and decided that there bronchitis when Moffat arrived for a two- “He saw in a way more clearly than any- we now call black holes: objects of such was some weakness in what he was doing,” day visit. During their interview, the great one else what quantum mechanics was re- enormous density that their gravity traps he says. “So I wrote two papers and sent physicist would peer at his young visitor ally like,”the British physicist Julian Barbour even light.“Einstein didn’t like black holes,” them to him at Princeton. I never thought through round, rimless spectacles. Moffat explains.“And he said,‘I don’t like it,’”In the Moffat says.“The real motivation for gen- I’d hear anything from him.” knew that he wouldn’t hesitate to dismiss years following the conference in Brussels, eralizing his gravity theory was to see if he Moffat had identified a mistaken as- him as an impostor and send him back to a Einstein leveled one attack after another at could find, as he called them,‘everywhere sumption in the mathematics Einstein was life of obscurity in Denmark. Once again, Bohr and his followers. But for each attack regular solutions’ that fit the equations.” using to describe the electromagnetic force. however, things went smoothly until Mof- Bohr had a ready riposte. Then in 1935 Ein- Such solutions, Einstein hoped, would Einstein conceded that Moffat had a point. fat mentioned his interest in Einstein’s work.