Pandora's Keepers Page 3

  After the war ended, Szilard returned to the Technical University, where revolutionary turmoil swirled around him. Students, artists, and intellectuals debated issues of the day in sidewalk cafés. Szilard thrived as the gadfly who asked the uncomfortable questions that others avoided. He was sympathetic to the communist regime that had come to power in Hungary at the end of the war under Béla Kun but recoiled at the brutalities that Kun inflicted in the name of the people and feared a conservative backlash. Szilard felt this backlash personally when he was confronted by angry students at the university who shouted, “You can’t study here. You’re Jews.” 9 They rushed Szilard, hitting and kicking him. The blood, bruises, and shame left Szilard with a fear of anti-Semitism that he would carry for years to come.

  Realizing that, as a Jew, he was in personal danger, Szilard decided to leave Hungary for the University of Berlin. He arrived in Berlin in 1920 and took the university by storm. Berlin’s physics faculty included giants such as Einstein, Max Planck, and Max von Laue, and Szilard sensed new developments in the air. In 1932 British physicist James Chadwick discovered the neutron. The neutron had no electric charge, which meant it could pass through the electrical barrier surrounding the atom and penetrate the nucleus. Szilard saw in the neutron’s ability to easily penetrate the nucleus the possibility of eventually releasing the vast store of energy contained within the atom.

  The same year as Chadwick’s discovery, Szilard moved from the University of Berlin to the Kaiser Wilhelm Institute, where he continued his experimental work in nuclear physics. As he probed the mysteries of the atom within the institute, he grew edgy as he observed what was happening outside its walls. Szilard noticed that most Germans stood passively watching the growing Nazi threat. When he asked his German friends, “Why don’t you oppose Nazism?” most of them shrugged and muttered, “What good would it do?” Szilard concluded that Hitler would gain power not because Nazism was so appealing to Germans but because so few Germans would resist it.

  Unlike most physicists during these years, Szilard had no illusions that things would get better. He saw Nazism for what it was: an evil force that spelled disaster for Germany and all of Europe. Months before Hitler came to power, and years before he engulfed Europe in a bloody war, Szilard’s assessment of the problems brewing for Jews in Germany led him to grave predictions. He shared them in a letter to Rabi, whom he had met and befriended in the late 1920s. “As far as the fate of Germany is concerned,” Szilard wrote Rabi, “I always was very pessimistic, but I range now with the optimists. (You know, an optimist is a man who jumps out of the window of the 22nd floor and who says smiling when he passes the 10th floor, falling down: ‘Well, nothing happened to me up till now.’)” 10 Szilard’s sarcasm belied his deep pessimism and despair.

  On the night of February 27, 1933, Nazi saboteurs set fire to the Reichstag, Germany’s parliament. Hitler blamed the arson on a Jewish-Communist plot and bullied Reichstag deputies into granting him dictatorial powers. On April first the Nazis directed a national boycott of Jewish businesses and beat Jews in the streets. On April seventh thousands of Jewish academics lost their positions in German universities. Szilard was particularly incensed by the prohibition against teaching “Jewish science”—any theory, even Einstein’s profound theory of relativity, that had been developed by a Jew. He decided the time had come to get out. He grabbed his suitcases and took the night train to Vienna. The following day Nazi border guards stopped the same train and held back everyone whose passport was stamped “non-Aryan.” This close call so traumatized Szilard that, forever after, he kept two suitcases packed and close at hand wherever he lived. 11

  In Vienna Szilard called on Western embassies and warned them that the Nazi assault on Jews was just beginning. The diplomats listened politely but said, and did, nothing. So Szilard decided to leave the Continent for the greater safety of Britain. He sought a permanent academic position there, but Depression-era Britain had only a limited ability to absorb refugees—there were neither enough positions nor enough money to fund them. Unable to secure a university appointment, Szilard decided to camp out in a modest hotel in London while he contemplated his next step. For the moment, he lived on the income from his patent licenses and money he had saved from tutoring fees.

  Szilard was an idea man par excellence. Each day for months he strolled London’s busy streets and beautiful parks pondering nuclear physics and his fears for Europe’s future. One afternoon, while walking on a sidewalk in Bloomsbury, he had a fateful idea. He later recalled:

  As the light changed to green and I crossed the street, it suddenly occurred to me that if we could find an element which is split by neutrons and which would emit two neutrons when it absorbed one neutron, such an element, if assembled in sufficiently large mass, could sustain a nuclear chain reaction. I didn’t see at the moment just how one would go about finding such an element or what experiments would be needed, but the idea never left me. 12

  Szilard imagined that if a neutron struck a nucleus and split the atom, the breakup might release the binding energy that holds the atom together. Some of that atom’s neutrons might in turn be released, which could hit and split other atoms. If more than one neutron was released from each split atom, the process could expand exponentially. “One neutron would release two, which would each strike an atomic nucleus to release four… and so on. In millionths of a second, billions of atoms would split.” 13

  Suddenly Szilard remembered the H. G. Wells novel he had read a year earlier. Published in 1914, just before the outbreak of World War I, The World Set Free prophetically described a conflict in which cities were destroyed by atomic bombs. “Of course,” Szilard wrote a friend to whom he sent a copy of the novel, “all this is moonshine, but I have reason to believe that the forecast of the writers may prove to be more accurate than the forecast of the scientists.” 14

  Szilard stood alone in his belief in a chain reaction. At the time, his mentor and friend Einstein—the world’s preeminent theoretical physicist—told reporters that such an effort would be “fruitless.” 15 Attempting to unlock the energy of the atom by neutron bombardment, said Einstein, was likely to enjoy about the same chance of success as “shooting birds in the dark in a country where there are only a few birds.” 16 A doyen of the scientific establishment, the great experimentalist Lord Ernest Rutherford dismissed the prospect of a chain reaction with devastating British understatement: “The outlook for gaining useful energy from atoms by artificial processes of transformation does not look promising.” 17 With comments like these the order of the day, it is easy to appreciate Szilard’s difficulty in getting support for exploring the possibility of a nuclear chain reaction.

  It was not an idle joke. Recognizing that the days of peace in Europe were numbered and that the future of Western civilization and modern science would depend on the degree of support that could be mustered in the New World, Szilard decided to emigrate to America. About Christmastime 1937 Szilard attended a dinner at Magdalen College in Oxford, where a fellow of the college told Szilard that he was leaving soon on a visit to the United States. “Buy a one-way ticket,” Szilard advised him. 18

  Szilard’s reasoning was simple. As he told a fellow Jewish refugee planning to leave the Continent, Britain was “a very likeable country, but it would certainly be a lot smarter if you went to America. In America you would be a free human being and very soon would not even be a stranger.” 19 In practical terms, he also saw a much better opportunity for nuclear physics research in the United States.

  In January 1938 Szilard decided the time had come to depart. He begged his parents in Budapest to join him, but they refused to budge—they were old and did not want to leave the only world they knew. Szilard could do nothing more than bid them a sad farewell. Once in New York, he found himself quickly and happily at home. Nazism was far away. He did not feel like a foreigner. When he had some difficulty adjusting, this nation of immigrants offered understanding and sympathy. He had felt much mo
re like a refugee in Europe.

  So, quickly and eagerly Szilard decided to become a U.S. citizen. Emotionally and politically, he felt that he already belonged irretrievably to America. In his thinking and action, he scarcely had any affinity with the mentality of Nazi Germany. Soon he was in touch with other refugee physicists in the United States and was visiting Columbia frequently to see Rabi. With Rabi’s help, Szilard resumed his research on the atomic nucleus and began warning anyone who would listen about the looming threat of Nazism.

  Although Szilard had conceived the idea of a chain reaction, he lacked the resources—a laboratory, assistants, and financial support—to search for it. That quest fell to another refugee physicist, Enrico Fermi, who had the resources that Szilard lacked—and the brains to match. In contrast to Szilard, who moved from one temporary job to the next, lived in hotel rooms, and proposed experiments to other people, Fermi was a well-established academic who ran a famous physics institute located in a small, quiet park on a hill in central Rome. The park, landscaped with palm trees, bamboo thickets, and a garden that attracted singing sparrows at dusk, made the institute a peaceful and attractive center of study.

  A short man with rounded shoulders, narrow nose, thick black hair, and hazel eyes that stood out against a dark complexion, Fermi charmed people by craning his neck forward and flashing a winning smile that exposed a gap between his front teeth. Quiet and unpretentious, he displayed an unusual combination of personal modesty and self-confidence. He wore a simple leather jacket and always drove his own car. When he encountered a roadblock in front of his institute one day, he leaned out the window and said, “I am His Excellency Enrico Fermi’s chauffeur”—which got him waved through. He had such a gift for seeing into the heart of problems and such an easy manner of solving them that other physicists nicknamed him “the Pope.”

  Fermi was born in 1901 into a middle-class family of civil servants and attended Italian public schools. He showed intellectual brilliance from an early age and also a cool, reserved manner. He was more prone to deeds than to talk and carefully guarded his innermost thoughts. Though somewhat cold, he was absolutely impartial. Fermi’s most striking trait was his willingness to accept the world and people as they were. “He took people around him at their own value,” said a friend. “That’s why I was very fond of him.” 20 He understood complex theories but preferred making simple points. Likewise, though he did not spend a lot of time analyzing people, he seldom misjudged them. Fermi abhorred confrontation and avoided battles that he was not confident of winning. If faced with superior force, he invariably withdrew from a contest. Consistent with this, he rarely made promises unless he was sure he could deliver on them.

  Fermi began his career as a physicist in 1922, the year he received his doctorate from the University of Pisa. That same year, Benito Mussolini marched on Rome at the head of his armed Black Shirts and seized control of the Italian government in the name of Fascism. Preoccupied as he was with physics, the menace of Fascism seemed remote to Fermi. In 1923 he won a fellowship to study in Germany with the renowned Max Born, who had gathered a group of brilliant young physicists around him at Göttingen, including Werner Heisenberg and Wolfgang Pauli. Heisenberg and Pauli did not bring Fermi into their circle of conversation; most of the time the young Italian worked alone in silence. As a result, Fermi, who had succeeded almost effortlessly until then, felt ignored and unappreciated at Göttingen, an unwelcome foreigner in Germany. The experience embittered Fermi, who would remember it for a long time to come.

  Fermi returned to Italy and took up a professorship of theoretical physics at the University of Rome. Over the next decade Fermi turned his physics institute into a leading center for the study of the nucleus. Fermi preferred tackling concrete problems. His method was never to waste time and to keep things as simple as possible—a no-nonsense, matter-of-fact, commonsense perspective. In this way, he kept going forward until he reached his goal, carefully and relentlessly. He was a master at achieving important results with a minimum of effort. Like Szilard, Fermi saw the significance of the neutron and designed experiments around it. He decided to bombard nuclei of atoms with neutrons and see what happened. Fermi’s insight was to slow neutrons down by sending them through paraffin (a particularly dense substance); the slower the neutrons moved, he thought, the more likely they were to stick in the nucleus they were hitting.

  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.” 21

  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. 22 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.” 23 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.