The Nuclear Option: Lise Meitner, Erwin Schrödinger, and the Science of Exile

In the 1920s, the front rows of the University of Berlin’s physics colloquium were stacked with Nobel laureates, including Albert Einstein, Max Planck, and Gustav Hertz. Lise Meitner was the only female professor in the room. Einstein called her “our Marie Curie,” and decades of leading her research team, culminating in some back-of-the-envelope calculations done on a holiday walk, eventually led to a Nobel Prize—but not for her.

Meitner was born into a secular Jewish Viennese family. Although they lived in the Leopoldstadt, Vienna’s historically Jewish district, the Meitners had little connection to their Judaism, and Lise leaned toward empiricism from an early age. Meitner’s biographer, Ruth Lewin Sime, tells a possibly apocryphal tale about the budding young scientist:

Once, when Lise was still very young, her grandmother warned her never to sew on the Sabbath, or the heavens would come tumbling down. Lise was doing some embroidery at the time and decided to make a test. Placing her needle on the embroidery, she stuck just the tip of it in and glanced anxiously at the sky, took a stitch, waited again, and then, satisfied that there would be no objections from above, contentedly went on with her work.

Meitner, slight, dark haired, with deep-set eyes, was nineteen when the University of Vienna began admitting women. At twenty-three, after working with a private tutor, she passed the entrance exam and began her study of physics in a rickety old building near Sigmund Freud’s home. “If a fire breaks out here,” she wrote, “very few of us will get out alive.” No fires broke out, and Meitner became the second woman in the university’s history to take a doctorate in physics.

In 1907, she boarded a train to Berlin, alone and unknown, to try to make something of herself as a researcher. She approached Planck, the father of quantum mechanics, for permission to audit his lectures. “He received me very kindly,” she recalled, “and soon afterwards invited me to his home. The first time I visited him there he said to me, ‘But you are a Doctor already! What more do you want?’”

She wanted to work as a physicist, and she did, for five years unpaid and supported by a modest allowance from her parents (who had seven other children to support). She worked with the chemist Otto Hahn on radioactive decay, but the laboratory officially barred women, so she conducted experiments in the basement.

In 1912, Planck finally made her his official assistant, the first woman to hold such a position in Prussia. Her collaborator Hahn worked nearby, at the newly formed Kaiser Wilhelm Institute for Chemistry. Study by study, paper by paper, she became one of the world’s foremost experts on radioactivity, founding the institute’s radiophysics department in 1917.

In the years after World War I, Meitner had barely enough to eat. She wrote to her mother in Vienna that she was not suffering, though “when one is over forty, a little student room is not quite the right thing.” Her research, at least, was grand. She built Berlin’s first cloud chamber, a new way to study the atomic nucleus, and worked at the forefront of nuclear physics. By the time that Erwin Schrödinger took a seat next to her at the Wednesday physics colloquium in 1927, Meitner was a star. So, of course, was Schrödinger, who had become renowned for a major breakthrough in quantum mechanics the year before and would later be remembered for his thought experiment about a cat.

Unlike Meitner’s, Schrödinger’s path to physics had been smooth. His father had studied chemistry, and his mother’s father was the chair of the chemistry department at the Technical University of Vienna. The same grandfather owned a palatial five-story apartment building in Vienna’s glittering First District, where Schrödinger grew up in the penthouse, a doted-upon only child. The war left him intact but destroyed his family’s wealth. He left Vienna in 1920 for an assistantship in Jena. His job was to update the theoretical physics lectures of Felix Auerbach, who had been denied a full professorship for decades on account of his Jewishness. As Schrödinger later recalled, “We enjoyed the friendship and cordiality of both the Auerbachs, who were Jews, and of my boss Max Wien and his wife (they were anti-Semites by tradition, but bore no personal malice).”

Later, in Berlin, he became close with Meitner. She may have been from the opposite side of Vienna’s Donaukanal, but they had both been raised to worship the Bildungskultur, the culture of learning, which valued literature, theater, and the cultivation of the life of the mind. Schrödinger’s wife, Annemarie, recalled, “With Lise Meitner in Berlin it was beautiful. We were very good friends.” The Schrödingers hosted merry Wiener Würstelabende (Viennese sausage evenings), attended by practically the whole physics community.

The trouble began after the stock market crash of 1929. Unemployment spiked, and by the summer of 1932, students were going hungry. Schrödinger’s teaching assistant Victor Weisskopf recalled, “Bands of young Nazis freely roamed the streets of Berlin,” beating up “Jewish students or those who looked Jewish,” and “More than once I had to pull one of the boys under attack into my office so that he could escape through the back door.”

On the morning of January 30, 1933, Meitner and Annemarie sat together in the Schrödingers’ apartment, listening to the radio as the Nazi storm gathered. They heard Hitler sworn in as chancellor at noon. The Schrödingers still planned the next Wiener Würstelabende, but it would be the last round of merrymaking.

Einstein immediately sensed the danger. In the United States, he canceled his upcoming lecture at the Prussian Academy of Sciences and wrote to a friend that he “dare not enter Germany because of Hitler.” He soon announced publicly:

As long as I have any choice in the matter, I shall live only in a country where civil liberty, tolerance, and equality of all citizens before the law prevail. . . . These conditions do not exist in Germany at the present time.

That semester, Meitner was acting director of the Kaiser Wilhelm Institute for Chemistry, and she wrote Hahn in March that the accounting office had “ordered us to estimate the cost of our national flag, because it is to be replaced with a black-white-red one which [the Kaiser Wilhelm Society] will pay for.” A swastika soon flew overhead, and Meitner went on with her work.

In April, the Nazis organized a boycott of Jewish-owned businesses. Then they implemented the Law for the Restoration of the Professional Civil Service, dismissing “politically unreliable” and “non-Aryan” appointees. The first of many supplements clarified that a civil servant was “non-Aryan” if they had one Jewish grandparent. Meitner had four.

Her university professorship was revoked that September, barring her even from the Wednesday physics colloquium. Still, her job at the institute was protected, as it was financed by private industry, not the state. Soon, Jewish physicists were fleeing Germany, and colleagues in England and America were hard at work resettling the refugee scientists. Many of the exiles continued to study the nuclear reactions that so fascinated Meitner. The neutron had been discovered the year before, and bombarding atoms with neutrons turned out to result in curious new physics. But Meitner did not want to leave her institute. Later, she wrote, “I had built it from the very first little stone; it was, so to speak, my life’s work, and it seemed so terribly hard to separate myself from it.”

Schrödinger felt differently. He had always described himself as “apolitical,” and he was of the purest “Aryan” blood, but Nazi Berlin was unattractive to him. His old friends from Jena, Felix Auerbach and his wife, had committed suicide together that February. They saw, Schrödinger said, “no means of escape from the oppression and humiliation which Hitler’s taking over held in store for them.”

Schrödinger soon announced that he wanted to move to Oxford, thereby becoming one of the few non-Jewish scientists to leave Germany in response to Hitler’s seizure of power. He informed the university he was taking only a “study leave,” but no one believed it. On vacation that summer, his friend Wolfgang Pauli raised the possibility that he might want to return to Berlin to oppose the Nazis. Schrödinger replied, “I’ve had a nose full—I want to get out.” When he and Annemarie arrived in Oxford that fall, he was awarded the Nobel Prize. But Schrödinger didn’t stay away from the German-speaking world for long. In 1936, he accepted a call to a professorship in Graz, Austria, accompanied by a part-time professorship in Vienna. By then, though, Austria was already in the Nazis’ sights.

After the Anschluss, Schrödinger was unwilling to uproot himself again. At the advice of the new Nazi rector of the university in Graz, he published a fawning letter in the Graz Tagespost under the headline “Confession to the Führer.” He would, he wrote, “be very happy, if in true cooperation and in accord with the will of the Führer [he would] be allowed to support the decision of his now united people with all [his] strength.” Not only that, but he continued:

It really goes without saying, that for an old Austrian who loves his homeland, no other standpoint can come into question; that—to express it quite crudely—every “no” in the ballot box [resisting unification with the Third Reich] is equivalent to a national [“völkisch”] suicide.

There ought no longer—we ask all to agree—to be as before in this land victors and vanquished, but a united people [“Volk”], that puts forth its entire undivided strength for the common goal of all Germans.

Here was Schrödinger obsequiously using the words völkisch and Volk, keywords in the lexicon of what the philologist Victor Klemperer called the Lingua Tertii Imperii. Schrödinger even said that he wanted to grasp Hitler’s “outstretched hand of peace,” the same hand that was reaching out to strangle his Jewish friends and colleagues.

His letter was widely reprinted in German newspapers and reported on in the British scientific journal Nature. His friends abroad feared it had been forced under threat of imprisonment or worse, but, in truth, he and Annemarie just wanted to stay in Austria. They were soon enjoying a spring skiing vacation in the Tyrol. A former Oxford colleague met Schrödinger there and reported that “he has clearly no feeling that it is necessary for him to get out of the country at all costs as soon as possible, and would on the whole like to make his peace with the regime if they will let him.” But the Nazis still didn’t trust him and canceled his professorships. Schrödinger, in fear of further repercussions, fled for England, where he was considerably less welcome than he had been a few years before.

Churchill’s scientific adviser, Frederick Alexander Lindemann, asked, “Is he mad? Doesn’t he realize after this letter he has published what people think of him?”The Jewish physicist Franz Simon wrote that Schrödinger’s arrival “caused a great stir here—with derisive remarks such as ‘he sold his soul’ and quotes of the saying of the King of Hannover: ‘Professors are as good as whores.’” Simon told Schrödinger that “it would be desirable if he would make it clear to his acquaintances that the letter had been written under pressure.” Simon recalled:

First, he asked, which letter? Then he became very abusive and excited. He said he was here in a land of freedom and what he was doing was nobody else’s business. He flatly refused to talk about this point at all.

 Schrödinger did explain himself to Einstein, writing, “I hope you did not seriously denounce my subsequent, certainly quite cowardly, behavior. I wanted to stay free—and couldn’t do it without gross hypocrisy.” But no public recantation followed. As huge numbers of his colleagues joined the Allied war effort, Schrödinger took a position in Dublin, cloistering himself above the fray.

Meanwhile, from 1933 to 1938, Meitner had remained at her institute in Berlin. After the Anschluss, she no longer had a valid passport, and her siblings in Vienna were in dire straits. She finally resolved to leave but was denied papers. Her friends hatched a plan. Dirk Coster, a Dutch physicist, visited her in Berlin and convinced her to sneak back over the Dutch border with him by train. Meitner remembered, “So as not to arouse suspicion, I spent the last day of my life in Germany in the institute until eight at night correcting a paper to be published by a young associate.” Hahn gave her his mother’s diamond ring to use in an emergency. On July 13, 1938, she successfully reached the Netherlands, and only just in time—a colleague had informed the authorities that she seemed ready to flee.

Meitner soon landed in a low-paid research position in Sweden. She worried in a letter to Hahn that her former staff believed that she had “abandoned her responsibilities.” She had none of her things, no money, and did not speak the language. Her siblings’ plight worried her sick. What kept her going was her constant correspondence with Hahn about mysterious isotopes of radium formed when uranium was irradiated with neutrons. That November, the week after both her sixtieth birthday and Kristallnacht, she met Hahn in Copenhagen and discussed these uranium reactions. On December 21, she received a letter describing a striking new result: Barium had been created. Meitner wrote back that this was only possible by a “thoroughgoing breakup” of uranium into lighter elements.

Over the Christmas holiday, she discussed the uranium “breakup” with her nephew Otto Frisch, who was a physicist working in Copenhagen (his father, Meitner’s brother-in-law, was in Dachau). On a walk through the snowy woods, they “sat down on a tree trunk, and started to calculate on scraps of paper,” Frisch recalled. They imagined the nucleus of uranium like a drop of water, split into two droplets by a slow neutron, Frisch said:

Fortunately, Lise Meitner remembered how to compute the masses of nuclei from the so-called “packing fraction formula,” and in that way she worked out that the two nuclei formed by the division of a uranium nucleus would be lighter than the original uranium nucleus by about one-fifth the mass of a proton.

Using Einstein’s famous formula, E = mc², she calculated the energy thus released. They christened this process nuclear fission in an elegant paper composed on long-distance phone calls over the next two weeks.

 Until her research team’s experiments and Meitner’s theoretical interpretation, no one dreamed that an atom could be split in half. But despite this momentous discovery, Meitner languished in Sweden, isolated and unsupported. She wrote incessant letters to help Jewish colleagues fleeing the Third Reich, but when she was invited to Los Alamos, New Mexico, in 1943 to work on the Manhattan Project, she refused, wanting nothing to do with creating an atomic bomb.

After the war, the American press dubbed her the “Mother of the Atomic Bomb.” American Jews embraced her as a heroine, but she wrote to her younger sister in September 1945:

I feel like an imposter when American Jews (or from my point of view one should say Jewish Americans) praise me especially, because I am of Jewish descent. I am not Jewish by belief, know nothing of the history of Judaism, and do not feel closer to Jews than other people.

And yet, unlike practically all of her Gentile colleagues, she recognized her own culpability for remaining at work while Hitler turned the screws on the Jewish people. She wrote to Hahn, “It is very clear to me that I committed a great moral wrong by not leaving in ’33, because staying had the effect of supporting Hitlerism.” Of her colleagues, only Planck agreed. When they met in Stockholm in 1943, he said to her, “We have done the most terrible things; terrible things must happen to us.”

After the war, the physicist Max von Laue wrote to her, “I am not sure that all those who assign blame would have acted differently if they had happened to have been born in Germany.” She begged her friends to see that active resistance had been morally necessary and that it had been wrong for them to help at most “some oppressed person here and there, [while] millions of people were murdered and there was no protest.” She wanted the whole civilized world to resolve that they would act differently if similar circumstances arose again.

Otto Hahn alone received a Nobel Prize, in chemistry, for the discovery of fission. Fritz Strassmann, with whom Hahn had done all the experiments, said Meitner’s “initiative was the beginning of the joint work” that led to the discovery. Strassmann acknowledged that Meitner “was the intellectual leader of our team” and “bound to us intellectually from Sweden,” despite her exile. But Meitner’s leadership and interpretation of the physics of fission went unnoticed by the Nobel Committee. Hahn minimized Meitner’s leadership, but his bigger sin, in her eyes, was his refusal to shoulder any accountability for what the Third Reich had wrought. He wrote to her, “One cannot do anything to counteract a terror regime. . . . How can one constantly reproach an entire people for their behavior during such time?”

Schrödinger also evaded responsibility. When some physicists resisted giving him an honor because of what Max Born called his “silly” “Confession to the Führer,” the Jewish physicist Rudolf Peierls said, “I would not pass it over by just describing it as ‘silly.’ Our distress at events in Germany surely was so bitter just because there were so many people who failed to understand the seriousness of the issues.” Schrödinger was given the honor anyway.

In 1947, Meitner was invited back to lead the Kaiser Wilhelm Institute for Chemistry under Hahn, who led the whole Kaiser Wilhelm Society. She wrote to a friend, “The Germans still do not comprehend what has happened, and they have completely forgotten all the horrors that did not personally happen to them. I think I would not be able to breathe in such an atmosphere.” She turned down the offer. It was too late anyway. The Wednesday physics colloquium had long since emptied out.