Meitner, Lise (1878–1968)

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Meitner, Lise (1878–1968)

Austrian theoretical physicist, and the first woman in Germany to hold the title professor, who made key contributions to the discovery of nuclear fission . Pronunciation: MITE-ner. Born Lise Meitner in Vienna, Austria, on November 7, 1878; died in Cambridge, England, on October 27, 1968; daughter of Hedwig (Skovran) Meitner and Philip Meitner; attended Academic High School, Vienna, and University of Vienna, 1902–06, awarded Ph.D.; never married; no children.

Awards:

Leibnitz Medal of the Berlin Academy of Sciences (1924); Lieber Prize of the Austrian Academy of Sciences (1925); City of Vienna's Prize in Science (1947); Max Planck Medal (1949); Enrico Fermi Award (1966).

Enrolled in Max Planck's lectures, University of Berlin (1907); met Otto Hahn (September 28, 1907) and began collaboration; with Hahn, discovered thorium c (1908); joined Kaiser Wilhelm Institute for Chemistry (1912); became research assistant to Max Planck (1912); was X-ray technician in the Austro-Hungarian Army (1914–18); appointed head of the Department of Physics, Kaiser Wilhelm Institute for Chemistry (1918); with Hahn, discovered protactinium (1918); became a privatdozent, University of Berlin (1919); appointed Professor Extraordinary, University of Berlin (1926); was one of the first to report that positrons were formed by gamma rays (1933); worked with Hahn to confirm Fermi's thesis (1934); fled Nazi Germany (1938); joined the Nobel Institute, Stockholm, Sweden (1938); identified nuclear fission (1939); refused to participate in the Manhattan Project (1942); was a visiting professor, Catholic University, Washington, D.C. (1946); retired from the Nobel Institute (1947); joined the Royal Institute of Technology, Stockholm, Sweden (1947); retired to Cambridge, England (1966); died a few weeks before her 90th birthday (1968).

Selected publications in English:

(with O.R. Frisch) "Disintegration of Uranium by Neutrons: A New Type of Nuclear Reaction," in Nature (1939); "Resonance Energy of the Th Capture Process," in Physical Review (1941); "Looking Back," in Bulletin of Atomic Scientists (1964).

On July 16, 1945, at 5:29 am, the world's first atomic bomb exploded in the New Mexico desert, marking the transition of humanity to the nuclear age. The implications of the blast that was heard around the world are still a matter of considerable conjecture. It can be said with certainty, however, that without the contribution of Lise Meitner, nuclear science would not have come about when it did.

Born in Vienna on November 7, 1878, Lise Meitner was one of seven children of Hedwig Meitner and Philip Meitner, a well-known attorney and converted Jew. Though his daughter's interest in physics was apparent from an early age, Philip insisted that she obtain a teaching diploma in order to support herself. After graduation, Lise took the entrance examination and, in 1902, was enrolled at the University of Vienna. By then, her father was willing to subsidize her education.

Fascinated by the work of Marie Curie , Lise Meitner studied theoretical physics under Ludwig Boltzmann. At the time, not all physicists agreed that the world was comprised of atoms. Fortunately for Meitner, Boltzmann was a firm advocate of the thesis. Notes Edna Yost , the debate had a long antecedence:

The Greek Democritus, who in the fifth century B.C. propounded the theory that all things are composed of invisible particles, all of them in constant motion, and all of them composed of the same matter but different in size, shape and weight, had named these tiny particles atoms because that is the Greek word for "indivisible." Nearly twenty-four centuries elapsed before science had been developed to the stage where men (and women) whose minds were receptive to the atomic theory had scientific equipment and accumulated knowledge to begin to investigate the validity of this theory.

In 1906, when Lise Meitner was awarded a Ph.D. from the University of Vienna, she was only the second woman to receive a doctorate from that institution. Her dissertation dealt with heat conduction in non-homogeneous substances. For a time, she remained in Vienna, undertaking research into radioactivity with Stephan Meyer.

In 1907, Meitner traveled to Berlin, drawn by the prospect of attending Max Planck's lectures on theoretical physics and envisaging only a short stay of one or two years. She also hoped to undertake postgraduate research. As a woman, however, she was barred from entering university laboratories. The Berlin of Meitner's day was a glittering citadel of science, attracting some of the most influential scientific minds of a generation: Max von Laue, Albert Einstein, Gustav Hertz, Max Planck, and Otto Hahn. It was also a city where attitudes towards women were slowly beginning to change.

When Lise Meitner met the gifted organic chemist Otto Hahn at a colloquium at the Institute of Physics on September 28, 1907, she was 29 and had already published two papers on radiation, "On the Absorption of Alpha and Beta Rays" and "On the Dispersion of Alpha Rays." The two scientists seemed an unlikely pair; Hahn was a convivial Rhinelander who enjoyed the outdoors, cigars, and beer, while Meitner was a petite, dark, and pretty Austrian who was morbidly shy. Hahn, an admirer of attractive women, noted: "There was no question of any closer relationship between us outside the laboratory. Lise Meitner had had a strict lady-like upbringing and was very reserved, even shy…. And yet we were really close friends." A scientific partnership soon blossomed, enabling Meitner to resume her research. The collaboration lasted for the next 30 years, and proved to be one of the most productive scientific alliances of the 20th century.

Meitner was a victim of the same patterns of prejudice which other women in academia faced. She and Hahn planned to work together at the Chemical Institute in Berlin, but its director, Emil Fischer, did not allow women on the premises. In Meitner's case, a compromise was reached, and she was allowed to work with Hahn provided she did not enter the laboratories where male students were taught. Though Meitner conscientiously kept her part of the bargain, in time Fischer "developed an attitude of fatherly friendship toward Lise Meitner," noted Hahn, and the rules were relaxed.

Meitner and Hahn equipped an old carpentry shop to serve as a laboratory. Here they measured the radioactivity of various substances. While Hahn, the chemist, was interested in the discovery of new compounds, Meitner focused on radiation research. Her inquiry built on the results of work done by Pierre and Marie Curie, Ernest Rutherford, and Niels Bohr. By 1908, Meitner and Hahn had discovered thorium c, and the editor of the Brockhaus Encyclopedia asked scientist Meitner to write an entry for the publication. Upon learning that scientist Meitner was a woman, however, he swiftly withdrew the offer.

Soon afterwards, Max Planck (originator of the quantum theory) asked Meitner to become his research assistant. Though few women held such a prestigious position, she served Planck for three years while continuing her work with Hahn. Then, on October 23, 1912, the Kaiser Wilhelm Institute of Chemistry was officially dedicated, and Hahn was invited to join the institute; he asked Meitner to follow him as a guest researcher. Finally, Meitner and Hahn had access to a first-class laboratory. The move was timely, because the old carpentry shop where the pair conducted their early research had become contaminated with radiation. In order to avoid a reoccurrence of this danger, Meitner and Hahn instituted rigorous safety precautions.

World War I disrupted their research. While Hahn served in an army unit specializing in gas warfare, Meitner returned to Austria and became an X-ray technician in a military hospital. As their experiments often took months to come to fruition, they made a virtue of necessity, and whenever their leaves coincided, Meitner and Hahn returned to Berlin and resumed their research.

In 1918, Lise Meitner, who had originally been banned from university laboratories, was asked to organize and head the Department of Physics at the Kaiser Wilhelm Institute. That same year, she and Hahn discovered protactinium. In the history of radioactivity, Lise Meitner was quickly emerging as the best-known female scientist since Marie Curie. The establishment of the Weimar Republic in 1919 opened the doors of academe to women. Shortly thereafter, Meitner became a privatdozent (lecturer without pay) at the University of Berlin.

Recognition of her work came in 1924, with the presentation of the Leibnitz Medal of the Berlin Academy of Sciences. A year later, the Lieber Prize of the Austrian Academy of Sciences was awarded. In 1926, Meitner was appointed Professor Extraordinary at the University of Berlin. She continued to focus on the differentiation of beta rays and gamma rays, working with her own independent research team. In 1933, she was one of the first to report that positrons were formed from gamma rays.

By the early 1930s, the science of nuclear physics was making rapid headway. Neutrons were discovered in 1932, positrons the following year, and the existence of artificial radiation was confirmed in 1934. Enrico Fermi, the Italian physicist, was obtaining interesting results by bombarding uranium with neutrons. He found that several radioactive elements were produced, which Fermi described as "elements beyond uranium." Fermi's research hinted that a peaceful use for nuclear energy might lie somewhere in the future. However, as Hahn noted, "among the results are also the atom bomb and the hydrogen

bomb!" Meitner and Hahn set out to confirm Fermi's results. The young chemist Fritz Strassmann soon joined the team.

Although of Jewish ancestry, Meitner was not initially affected by the rise of National Socialism. On April 7, 1933, all non-Aryans were barred from teaching in Germany. Since Meitner was an Austrian citizen, however, the new Nazi legislation did not apply to her. The early "years of the Hitler regime," she said, "were naturally very depressing. But work was a good friend, and I have often thought and said how wonderful it is that by work one may be granted a long respite of forgetfulness from oppressive political conditions." It was not until the German annexation of Austria in 1938 that Meitner lost her position at the Kaiser Wilhelm Institute. The German government deemed her to be "over 50 percent non-Aryan." "Lise Meitner had always kept quiet about her Jewish connection," said her nephew Otto Frisch. "She had never in any way related to the Jewish tradition." Meitner, Hahn, and Strassmann were on the threshold of solving the mystery of nuclear fission when Meitner was forced to flee Berlin. Her loss was deeply felt by Hahn and marked the end of their long collaboration.

Since Meitner attempted to escape Germany without a valid passport, she was terrified:

I took a train for Holland on the pretext that I wanted to spend a week's vacation. At the Dutch border, I got the scare of my life when a Nazi military patrol of five men going through the coaches picked up my Austrian passport which had expired long ago. I was so frightened, my heart almost stopped beating. I knew that the Nazis had just declared open season on Jews, that the hunt was on. For ten minutes I sat there and waited, ten minutes that seemed like so many hours. Then one of the Nazi officials returned and handed me back the passport without a word. Two minutes later I descended on Dutch territory, where I was met by some of my Holland colleagues.

From Holland, Meitner traveled to Copenhagen where she stayed with Niels Bohr and his wife Margrethe Bohr . Although the Danish capital boasted excellent research facilities, as well as well-known scientists, such as Otto Frisch, Meitner chose to move on, and accepted the offer of a position at the Nobel Institute in Stockholm. At 60 years of age, she set out to assemble a small research group and quickly acquired a command of the Swedish language. She also set to work on a number of monographs dealing with the properties of radioactive elements.

A few months after her arrival in Stockholm, Hahn and Strassmann completed their research in Berlin. They discovered that uranium atoms produced barium when bombarded by neutrons. As chemists, however, they were puzzled by these results. Hahn wrote to Meitner on December 19, 1938, informing her of the discovery. In the same month, Otto Frisch visited his Aunt Lise in Sweden. He found her engrossed in the letter from Hahn. Frisch reported:

We walked up and down in the snow … and gradually the idea took shape that this was no chipping nor crackling of the nucleus but rather a process to be explained by Bohr's idea that the nucleus was like a liquid drop; such a drop might elongate and divide itself. But how can one get a nucleus of barium from one of uranium…. Could it be that the nucleus got cleaved right across like a chisel? It seemed impossible that a neutron could act like a chisel, and anyhow the idea of a nucleus as a solid object that could be cleaved was all wrong; a nucleus was much more like a liquid drop. Here we stopped and looked at each other.

Over the Christmas holidays, Meitner and Frisch theorized that the positively charged protons within the uranium nucleus repelled each other, and separated into different chemical compounds. In an article co-written with Frisch, "Disintegration of Uranium by Neutrons: A New Type of Nuclear Reaction," Meitner identified the process as "atomic fission," a term first used by her. Employing Einstein's mass energy equivalence theory, she calculated that 200 million electron volts of energy had been created during Hahn's experiment. A few months later, Meitner and Frisch reproduced the experiment and confirmed their hypothesis. The experiment was also reproduced by scientists in Europe and North America.

With the inauguration of the Manhattan Project in the United States, Lise Meitner was invited to participate. She declined the offer on moral grounds, and fervently hoped that the project to build an atomic bomb would fail. "It is an unfortunate accident that this discovery [nuclear fission] came about in time of war," she commented. Except for brief experiments on the asymmetry of fissionable fragments, Meitner never worked on nuclear fission again.

In 1944, Otto Hahn received the Nobel Prize for the discovery of nuclear fission. His results were heavily dependent on the research of Lise Meitner, whom he did not acknowledge and whom the Nobel selection committee ignored. That she had been forced to flee Berlin just before their research bore fruit can account for this exclusion in part. Hahn and Strassman discovered that slow neutrons bombarding uranium produce barium, the first evidence that the uranium atom can be split. This discovery led to the first controlled nuclear reaction and to the first atomic bomb. Without Lise Meitner's expertise, however, their experiment would have been devoid of theoretical meaning. Even today, entries on Hahn in many wide-circulation encyclopedias refer to him as the sole "father" of nuclear fission, and, while those entries may include mention of Strassman, they make no mention of Lise Meitner or of her critical role in the achievement of nuclear fission.

After World War II, Meitner spent a semester as a visiting professor at the Catholic University in Washington, D.C. Leaving the Nobel Institute in 1947, she undertook research at the Royal Institute of Technology. In the same year, she was awarded the City of Vienna's Prize in Science, and two years later received the Max Planck Medal.

Meitner retired to Cambridge, England, in 1960. Much celebrated in later life, on July 29, 1966, she was honored with the Enrico Fermi Award. The dedication read in part:

The President of the United States of America … awards … the Enrico Fermi Award to Lise Meitner for pioneering research in the naturally occurring radioactivities and extensive experimental studies leading to the discovery of fission.

At the turn of the century, women in science were still scorned. As Hahn pointed out:

Lise Meitner's career is an interesting illustration of the difficulties which confronted a woman interested in an academic career at the beginning of the twentieth century…. Ofcourse she could not become a Privatdozent; at that time there were no female professors of any rank in Berlin. But in 1912 Planck took the step of making her an "assistant" at the Institute for Theoretical Physics of the University of Berlin. I think she was one of the first female scientific assistants in all Prussia…. After World War One women were admitted to academic careers, and Lise Meitner was able to become Privatdozentin…. But to many the concept of a "scientific female" was still somewhat weird.

Despite sexual and racial discrimination, Lise Meitner never failed to contribute to the field which, as a woman, she both pioneered and dominated. Indeed, Albert Einstein, ignoring her Austrian birth, once described her as "the German Madame Curie." Her collaboration with Hahn led to the discovery of new chemical elements, and ultimately to the discovery of nuclear fission. Said Meitner: "I believe all young people think about how they would like their lives to develop, when I did so I always arrived at the conclusion that life need not be easy, provided only that it was not empty. And this wish I have been granted."

sources:

Boorse, Henry A., Lloyd Motz, and Jefferson Hane Weaver. The Atomic Scientists. NY: John Wiley and Sons, 1989.

Ermenec, Joseph J., ed. Atom Bomb Scientist's Memoirs, 1939–1945. Westport, CT: Meckler, 1989.

Hahn, Otto. A Scientific Autobiography. Translated by Willy Ley. NY: Scribner, 1966.

Hermann, Armin. The New Physics. Translated by David C. Cassidy. Munich: Inter Nationes: 1979.

Jones, Lorella M. "Intellectual Contributions of Women to Physics," in Women in Science. G. Kass-Simon and Patricia Farnes, eds. Bloomington: Indiana University Press, 1990.

Libby, Leona Marshall. The Uranium People. NY: Scribner, 1979.

Yost, Edna. Women of Modern Science. NY: Dobb, Mead, 1964.