Pandora's Keepers (5 page)

Fermi began his neutron experiments in the mid-1930s in typically methodical fashion: by systematically bombarding all the elements in the periodic table. He started with water—testing hydrogen and oxygen at the same time—and finally came to uranium, one of the heaviest elements.

The results were puzzling. Fermi observed that the uranium nucleus captured the bombarding neutron, emitted an unusually large amount of radiation, temporarily became a heavier isotope (with the same chemical characteristics but a different atomic weight), then decayed to an element heavier by one atomic number. The simplest explanation consistent with the known facts—the yardstick typically applied by scientists to interpret experimental results—was that the uranium was mutating up the periodic table. These man-made, very heavy “transuranic” elements should be unstable: their radioactive breakdown could explain the copious radiation being emitted.

During these years Fermi grew increasingly alarmed by Mussolini’s policies, first the invasion of Ethiopia, then the intervention alongside Nazi Germany in the Spanish civil war. And there was something else: although anti-Semitism was not yet an issue in Italy, Fermi’s beloved wife, Laura, was Jewish. In 1936 Fermi traveled to the United States to lecture at the University of Michigan summer school, where he came into contact with a large number of American and visiting European physicists. Fermi liked what he saw at Ann Arbor: well-equipped labs, eager students, and plenty of praise for his scientific talent. He returned the next two summers as well. Each visit made him like America’s people, culture, and institutions more and more. At the same time, he gained perspective on Fascist Italy. America increasingly looked like the future to him, a land of freedom and opportunity far from the troubles of Europe.

Back in Italy, Fermi remained outwardly friendly, but now he kept his own counsel with all but his closest friends. As long as Fermi felt he could work unhindered in physics, he tried to ignore the nature of the Fascist regime and the trend of events. Like many of his countrymen, he tried not to see the unfolding truth, because it was too unpleasant to contemplate. But the atmosphere in Italy took a sharp turn for the worse in July 1938. That month Mussolini published the
Manifesto della Razza
, which announced that “Jews do not belong to the Italian race.” The manifesto was soon followed by edicts copied from Nazi racial laws. Not long after, the Fascist press began attacking Fermi for “having transformed the physics institute into a synagogue.”
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Fermi realized that it was time to get his family out of Italy. He wrote to four American universities that had expressed an interest in hiring him. To avoid suspicion, he mailed each letter from a different location in Rome. When all four responded favorably, Fermi chose Columbia University and awaited an opportunity to make his escape. Listening to the radio on the night of November 10, 1938, Fermi and his wife heard that he had won the Nobel Prize during the same broadcast that reported the horrors of Kristallnacht, the murderous anti-Jewish pogrom that had swept Germany the night before, and the institution of a new set of racial laws excluding Italian Jewish children such as their own son and daughter from public schools.

Fermi decided to use the Nobel ceremony in Sweden to spirit his family out of Italy. In early December he, Laura, and their two children left by train for Stockholm. There were tense moments along the way. When they crossed the frontier from Switzerland into Germany, a Nazi border guard slowly and deliberately flipped through their passports. Fermi watched anxiously until the guard moved on to the next compartment. He and his family reached Stockholm safely, where he received the Nobel Prize on December tenth. Two weeks later, on Christmas Eve, the Fermis left for New York. A short time later, Laura Fermi’s Jewish father, who had been an admiral in the Italian navy, disappeared into a concentration camp and was never heard from again.

Upon arriving in New York, the Fermis put up at the King’s Crown Hotel, on West 116th Street just east of the Columbia University campus, where Szilard had also settled. Szilard had exchanged experimental data about neutrons with Fermi since 1936, so the two men had much to discuss when they inadvertently bumped into each other in the hotel lobby one morning.
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Fermi was a scientific celebrity because of his recent Nobel Prize. Szilard, by contrast, had kept his pioneering nuclear research secret out of fear that the Nazis would somehow learn about it and use it to make an atomic bomb. “You didn’t know what he was up to” was the complaint around Columbia’s new Pupin Laboratory. “He was always a bit mysterious.”
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As a result, most Columbia physicists looked upon Szilard as an inconvenient interloper who nosed around faculty offices and showed up uninvited in the lab to pester and offer unwanted advice.

One physicist at Columbia knew both men well: Rabi. Rabi bridged the world of transatlantic physics, counting both native-born and refugee physicists as personal friends. He had first met Fermi and Szilard in Germany during the 1920s and had remained in touch with both ever since. He shared with Fermi a passion for physics, but with Szilard he shared even more: similar roots. Although their temperaments were very different—Rabi was affable, politic, and of a sunny disposition, while Szilard was eccentric, impolitic, and moody—they were both Jews who hailed from Central Europe, and thus shared certain shadows.

Isador Isaac Rabi was born in 1898 in a village in what is now Poland but was then the northeasternmost province of the Austro-Hungarian Empire. His parents emigrated to America before he was a year old. “Had we stayed in Europe,” he later said, “I probably would have become a tailor.”
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Like millions of other turn-of-the-century immigrants, the Rabis settled in the crowded Lower East Side of New York. It was a tough neighborhood where youngsters grew up fast. A contemporary of Rabi’s described the neighborhood’s “wisdom of the streets”:

We would roam through the city tasting the delights of freedom, discovering possibilities far beyond the reach of our parents. The streets taught us the deceits of commerce, introduced us to the excitement of sex, schooled us in strategies of survival, and gave us our first clear idea of what life in America was really going to be like.

We might continue to love our parents and grind away at school and college, but it was the streets that prepared the future. In the streets we were roughened by actuality, and even those of us who later became intellectuals or professionals kept something of our bruising gutter-worldliness, our hard and abrasive skepticism. You could see it in cab drivers and garment manufacturers, but also in writers and professors who had grown up as children of immigrant Jews.
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Synagogues and saloons coexisted on nearly every Lower East Side street, and these contradictory symbols of life in the Jewish ghetto seemed vivid symbols to the young Rabi of the ways of people and the world. The streets made him impish, quick-witted, buoyant, and brash. He always said exactly what he thought, whether or not he believed it would meet with approval. He was cynical, yet compassionate toward others.

Against the worldliness of the streets stood the piety of his parents, David and Sheindel Rabi, devout Jews who raised their son according to strict Orthodox tradition. Hardly a sentence went by in their conversation without a reference to God. Rabi’s earliest reading was Yiddish Bible stories. When he was nine years old, his family moved to Brownsville, the Jewish enclave of Brooklyn. One day as he browsed in the local branch of the Carnegie public library near his parents’ small grocery store, he stumbled on a book about astronomy. The explanatory power of the Copernican system impressed him deeply. “It was so beautiful, so marvelous,” said Rabi years later. “Instead of the idea that there is some special intervention every day for the sun to come up, I came home with this great revelation.” Pleased with himself, Rabi announced to his parents: “It’s all very simple, who needs God?”
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Rabi began testing other assumptions as well. Orthodox law forbade riding streetcars on the Sabbath. One Saturday he rode a streetcar, expecting God to strike it (or at least him) with lightning, but nothing happened. In synagogue, rabbis held out their tallis-covered hands; the congregation averted its eyes at the risk of blindness. One day Rabi did not, and again nothing happened. As Judaism began to look more and more like superstition to him, his life outside home became increasingly secular as he abandoned the religious practices and rituals of his immigrant parents. But the moral perspective of his Orthodox upbringing—the struggle between good and evil in the world—continued to shape his outlook. “My early upbringing, so struck by God, the maker of the world, this stayed with me,” Rabi later said. “There’s no question that basically, somewhere way down, I’m an Orthodox Jew.”
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Rabi’s testing of Jewish ritual and his growing exhilaration with science reflected a search for some all-encompassing system to explain both the universe and, more personally, the hard life of his family and friends. As an adolescent, he began to read books about Marxism and to attend neighborhood meetings of the Socialist Club. After a while, though, Rabi began to feel that Marxists were either kidding themselves or trying to kid him. “Part of the Socialist thing was ‘equality’—anybody can do this or that,” he recalled later. “But after I went to high school and looked at my classmates, I said, ‘Those people can’t run a government or a world,’ and dropped the whole thing.”
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When Rabi finished high school in 1916, his parents forcefully suggested that he go into Hebrew studies at a yeshiva. Instead, he decided to break away by going “way out west” to Cornell University in upstate New York. Ithaca, with its spectacular waterfalls and nearby Finger Lakes, certainly seemed like romantic country to a New York City boy who had devoured the novels of James Fenimore Cooper. Rabi scraped together enough money to attend college by summering as a sales clerk at Macy’s department store and winning two state scholarships. Once at Cornell, he enthusiastically immersed himself in Ivy League culture—but it was not a total immersion: Rabi reaped its rewards, but he also refused to change his personality or diminish his independence.

When Rabi graduated with a degree in chemistry in 1919, he couldn’t find a good job because of anti-Semitism and a postwar recession, so he returned to Cornell for graduate study. He soon realized that he should change his focus. His Orthodox upbringing had given him a feeling for the mystery of physics, a taste for generalization, and a belief in the profundity and underlying unity of nature. “When you’re doing physics, you’re wrestling with a champ,” he liked to say. “You’re trying to find out how God made the world, just like Jacob wrestling with the angel.”
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Physics brought Rabi nearer to God because the world was his creation. And like God, physics was infinite and certainly not trivial; it had class and drama. Doing good physics was “walking the path of God.”
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A decade later Rabi was a full professor at Columbia University and an accomplished physicist. He liked the atmosphere of the laboratory, but he was completely uninterested in details—decidedly hands-off. He studiously avoided nuts-and-bolts issues. “When things were going well and you were getting interesting data,” said one of his graduate students, “he was right there on top of the experiment helping with the interpretation. But when there were leaks in the apparatus, he just disappeared.”
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His way of training theoretical physicists was to tell a young man when he arrived that if he was bright enough to be a theoretical physicist, then he was bright enough to find his own problem, solve it, and, when he was finished, come back and tell him all about it.

In 1931 Rabi spent a year at the University of Hamburg, where he watched brown-shirted Nazi hooligans march past the university in an eerie torchlight parade. His Hamburg professors at first dismissed Nazism because the brownshirts were so few in number and so coarse. But his wife, Helen, attending a nearby art school whose students included several Nazis, had a very different and more troubling view. She did not look Jewish, and Nazi students therefore talked openly to her. They told her about the “next war,” and there was no doubt whatsoever about their vicious anti-Semitism. Rabi grew more alarmed when Hitler became chancellor in 1933. By then he was back in the United States at Columbia, but he had extensive contacts in Germany, including Szilard, who relayed what was happening there in frightening detail.

When Szilard arrived at Columbia in 1938, he shared with Rabi his idea of a chain reaction and his concern about what it meant for Europe. When Fermi arrived early the following year, the three physicists began a close collaboration. To work on the problems of fission and a chain reaction attended to all of their concerns at once: it was at the center of their scientific interests, the practical consequences might be enormous, and nothing could be more important politically than to guard against the danger that Nazi Germany might get an atomic bomb first. Like Szilard and Fermi, Rabi had become increasingly alarmed by Hitler and feared that the United States might stand by and allow him to take over Europe. Rabi began thinking about what he could do as a physicist to help in the war that he saw coming and that he felt sure would eventually involve America.

Niels Bohr also saw war coming. As a theoretical physicist, Bohr was thrilled and excited by the discovery of fission; but as a Danish Jew, he feared that Nazi Germany might use the discovery to make an atomic bomb. This fear was written on Bohr’s face when he arrived in New York in January 1939 to spend a semester at the Institute for Advanced Study in Princeton, New Jersey. “He stooped like a man carrying a heavy burden,” said a friend who saw Bohr standing on the deck of his ship as it pulled alongside the Hudson River pier. “His gaze, troubled and insecure, shifted but stopped on no one.”
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