Lise Meitner (November 17[1], 1878 – October 27, 1968) was an Austrian physicist who studied radioactivity and nuclear physics.
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Born in Vienna, Austria, Lise Meitner was the third of eight children of Philipp Meitner, a freethinking liberal Jewish lawyer, still remembered as a minor chess master, and his wife Hedwig. In later life she recalled their "unusual goodness" and the intellectual atmosphere of their house. With their help and private tuition she became one of the first to take advantage of recent relaxations in Austrian regulations limiting access to further education for women. She entered the University of Vienna in 1901, studying physics under Ludwig Boltzmann. In 1905, she obtained her PhD in physics, the first woman to do so at that university. After Boltzmann's death in 1907, she went to Berlin to work with the chemist Otto Hahn at the Kaiser Wilhelm Institute for Chemistry. Although the director of the Institute, Emil Fischer, would not allow a woman to work in his laboratories, she was allowed to work in the basement.[2]
Meitner worked closely with Hahn for 30 years (while retaining her Austrian citizenship), studying radioactivity with her knowledge of physics and his knowledge of chemistry. During World War I, she supported Hahn's collaboration with Fritz Haber in the development of the use of chlorine gas as a military weapon, although she did not participate in this work herself.[3] In 1918, she and Hahn discovered the first long-lived isotope of the element protactinium. In 1923, she discovered the radiation-less transition known as the Auger effect, which is named for Pierre Victor Auger, a French scientist who independently discovered the effect in 1925.
In 1926, she became a full professor at the University of Berlin; she was the first woman in Germany to achieve this rank in any field of study.
With the discovery of the neutron in the early 1930s, speculation arose in the scientific community that it might be possible to create elements heavier than uranium (atomic number 92) in the laboratory. A scientific race began between Ernest Rutherford in Britain, Irene Joliot-Curie in France, Enrico Fermi in Italy, and the Meitner-Hahn team in Berlin. At the time, all concerned believed that this was abstract research for the probable honor of a Nobel prize. None suspected that this research would culminate in nuclear weapons.
When Adolf Hitler came to power in 1933, Meitner was acting director of the Institute for Chemistry while Hahn was lecturing in the United States. Although she was protected by her Austrian citizenship, she had to watch while all other Jewish scientists, including her nephew Otto Frisch, Haber, Albert Einstein, Leo Szilard and many other eminent figures, were dismissed or forced to resign from their posts - most of them emigrating. Her response was to say nothing and bury herself in her work. In 1946 she acknowledged that "It was not only stupid but also very wrong that I did not leave at once."[4]
In March 1938 Germany annexed Austria, and Meitner found herself a German citizen and thus exposed to Germany's anti-Semitic laws (in fact, since German Jews had been stripped of their status as citizens in by the Nuremberg Laws of 1935, she was now only a German "state subject.") The fact that she was a convert to Lutheranism and did not consider herself Jewish was irrelevant to Nazi German law. Hahn, her close friend and collaborator for 30 years, dismissed her from the Institute and made no effort to protect or assist her: she never forgave him for this betrayal, although they later continued to work together.[5] She was unable to emigrate because her Austrian passport was invalid and she could not obtain a German one.
After several months in a legal limbo, Meitner was offered a refuge in the Netherlands by Dirk Coster of Groningen University who promised her an appointment there. She was forced to travel incognito to the Dutch border, where Coster persuaded German immigration officers that she had permission to travel to the Netherlands. She thus reached safety, though without her possessions. The appointment at Groningen did not eventuate, and she went instead to Stockholm, where she took up a post at Manne Siegbahn's laboratory, despite the difficulty caused by Siegbahn's prejudice against women in science. Here she established a working relationship with Niels Bohr, who travelled regularly between Copenhagen and Stockholm. She continued to correspond with Hahn and other German scientists.[6]
Hahn and Meitner met clandestinely in Copenhagen in November to plan a new round of experiments; in this regard they subsequently exchanged a series of letters. The experiments which provided the evidence for nuclear fission were done at Hahn's laboratory in Berlin. This surviving correspondence indicates that Hahn believed nuclear fission was impossible until Meitner demonstrated to him that it had happened. She was the first person to realize that the nucleus of an atom could be split into smaller parts: uranium nuclei had split to form barium and krypton, accompanied by the ejection of several neutrons and a large amount of energy (the latter two products accounting for the loss in mass).
A letter from Bohr, commenting on the fact that the amount of energy released when he bombarded uranium atoms was far larger than had been predicted by calculations based on a non-fissile core, sparked the inspiration in December of 1938. Meitner's supporters claim that Meitner was the first to do the prediction calculations for a fissile nucleus, yet they have been unable to provide evidence to support Meitner. Hahn claimed that his chemistry had been solely responsible for the discovery.
It was politically impossible for the exiled Meitner to publish jointly with Hahn in 1939. Hahn published the chemical findings in January 1939 and Meitner published the physical explanation the following month with her nephew, physicist Otto Robert Frisch, and named the process "nuclear fission".[7] Meitner recognized the possibility for a chain reaction of enormous explosive potential. This report had an electrifying effect on the scientific community. Because this could be used as a weapon, and since the knowledge was in German hands, Leo Szilard, Edward Teller, and Eugene Wigner together jumped into action, persuading Albert Einstein, who had the celebrity, to write President Franklin D. Roosevelt a warning letter; this led directly to the establishment of the Manhattan Project. Meitner refused an offer to work on the project at Los Alamos, declaring "I will have nothing to do with a bomb!"[8]
In 1944, Hahn received the Nobel Prize for Chemistry for the discovery of nuclear fission. In the opinion of many scientists, Meitner should have shared the prize. The omission may have been due to Hahn's public claims that the discovery was solely the work of chemistry; speculation also persists that — as Siegbahn was a Nobel committee member — his antipathy toward Meitner played a role as well. However, in 1966 Hahn, Fritz Straßmann and Meitner together were awarded the Enrico Fermi Award. On a visit to the USA in 1946 she received American press celebrity treatment as someone who had "left Germany with the bomb in my purse". She was honored as "Woman of the Year" by the National Women's Press Club (USA) in 1946, and received the Max Planck Medal of the German Physics Society in 1949.
After the war, Meitner, while acknowledging her own moral failing in staying in Germany from 1933 to 1938, was bitterly critical of Hahn and other German scientists who had collaborated with the Nazis and done nothing to protest against the crimes of Hitler's regime. Referring to the leading German scientist Werner Heisenberg, she said: "Heisenberg and many millions with him should be forced to see these camps and the martyred people." She wrote to Hahn:
Meitner became a Swedish citizen in 1949, but moved to Britain in 1960 and died in Cambridge in 1968. Element 109 is named meitnerium in her honor.
Although born to and raised by a Jewish family, Meitner became a Lutheran as a young adult, and remained so the rest of her life. She did not consider herself to be Jewish and she objected to accounts after the war that identified her as Jewish. This made no difference to the Nazis who persecuted her anyway, on perceived racial grounds.