| Lise Meitner | |
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Lise Meitner (1878–1968), photo taken in 1900
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| Born | 7 November 1878 Vienna, Austria |
| Died | 27 October 1968 (aged 89) Cambridge, England |
| Residence | Austria, Germany, Sweden United Kingdom |
| Citizenship | Austro-Hungarian (pre 1919), Austria (pre-1949), Sweden (post-1949) |
| Fields | Physics |
| Institutions | Kaiser Wilhelm Institute University of Berlin |
| Alma mater | University of Vienna |
| Doctoral advisor | Ludwig Boltzmann |
| Other academic advisors | Max Planck |
| Doctoral students | Arnold Flammersfeld Kan-Chang Wang Nikolaus Riehl |
| Other notable students | Max Delbrück Hans Hellmann |
| Known for | Nuclear fission |
| Influenced | Otto Hahn |
| Notable awards | Lieben Prize (1925) Max Planck Medal (1949) Enrico Fermi Award (1966) |
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Lise Meitner FRS[1] (7 November 1878 – 27 October 1968) was an Austrian-born, later Swedish, physicist who worked on radioactivity and nuclear physics.[2] Meitner was part of the team that discovered nuclear fission, an achievement for which her colleague Otto Hahn was awarded the Nobel Prize. Meitner is often mentioned as one of the most glaring examples of women's scientific achievement overlooked by the Nobel committee.[3][4][5] A 1997 Physics Today study concluded that Meitner's omission was "a rare instance in which personal negative opinions apparently led to the exclusion of a deserving scientist" from the Nobel.[6] Element 109, Meitnerium, is named in her honor.
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Meitner was born into a Jewish family as the third of eight children in Vienna, 2nd district (Leopoldstadt). Her father, Philipp Meitner,[7] was one of the first Jewish lawyers in Austria.[5] She was born on 7 November 1878. She shortened her name from Elise to Lise.[8][9] The birth register of Vienna's Jewish community lists Meitner as being born on 17 November 1878, but all other documents list it as 7 November, which is what she used.[10] As an adult, she converted to Christianity, following Protestantism,[10] and being baptized in 1908.[11]
Inspired by her teacher, physicist Ludwig Boltzmann, Meitner studied physics and became the second woman to obtain a doctoral degree in physics at the University of Vienna in 1905 ("Wärmeleitung im inhomogenen Körper").[5] Women were not allowed to attend institutions of higher education in those days, but thanks to support from her parents, she was able to obtain private higher education, which she completed in 1901 with an "externe Matura" examination at the Akademisches Gymnasium. Following the doctoral degree, she rejected an offer to work in a gas lamp factory. Encouraged by her father and backed by his financial support, she went to Berlin. Max Planck allowed her to attend his lectures, an unusual gesture by Planck, who until then had rejected any women wanting to attend his lectures. After one year, Meitner became Planck's assistant. During the first years she worked together with chemist Otto Hahn and discovered with him several new isotopes. In 1909 she presented two papers on beta-radiation.
In 1912 the research group Hahn-Meitner moved to the newly founded Kaiser-Wilhelm-Institut (KWI) in Berlin-Dahlem, south west in Berlin. She worked without salary as a "guest" in Hahn's department of Radiochemistry. It was not until 1913, at 35 years old and following an offer to go to Prague as associate professor, that she got a permanent position at KWI.
In the first part of the First World War (World War I), she served as a nurse handling X-ray equipment. She returned to Berlin and her research in 1916, but not without inner struggle. She felt in a way ashamed of wanting to continue her research efforts when thinking about the pain and suffering of the victims of war and their medical and emotional needs.[12]
In 1917, she and Hahn discovered the first long-lived isotope of the element protactinium, for which she was awarded the Leibniz Medal by the Berlin Academy of Sciences. That year, Meitner was given her own physics section at the Kaiser Wilhelm Institute for Chemistry.[5]
In 1922, she discovered the cause, known as the Auger effect, of the emission from surfaces of electrons with 'signature' energies.[13] The effect is named for Pierre Victor Auger, a French scientist who independently discovered the effect in 1923.[14]
In 1926, Meitner became the first woman in Germany to assume a post of full professor in physics, at the University of Berlin. There she undertook the research program in nuclear physics which eventually led to her co-discovery of nuclear fission in 1939, after she had left Berlin. She was praised by Albert Einstein as the "German Marie Curie".[15][16]
In 1930, Meitner taught a seminar on nuclear physics and chemistry with Leó Szilárd. 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, Irène 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 honour 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. Although she was protected by her Austrian citizenship, all other Jewish scientists, including her nephew Otto Frisch, Fritz Haber, Leó Szilárd and many other eminent figures, were dismissed or forced to resign from their posts. Most of them emigrated from Germany. Her response was to say nothing and bury herself in her work; she later acknowledged, in 1946, that "It was not only stupid but also very wrong that I did not leave at once."[17]
After the Anschluss, her situation became desperate. In July 1938, Meitner, with help from the Dutch physicists Dirk Coster and Adriaan Fokker, escaped to the Netherlands. She was forced to travel under cover to the Dutch border, where Coster persuaded German immigration officers that she had permission to travel to the Netherlands. She reached safety, though without her possessions. Meitner later said that she left Germany forever with 10 marks in her purse. Before she left, Otto Hahn had given her a diamond ring he had inherited from his mother: this was to be used to bribe the frontier guards if required. It was not required, and Meitner's nephew's wife later wore it.
Meitner was lucky to escape, as Kurt Hess, a chemist who was an avid Nazi, had informed the authorities that she was about to flee. An appointment at the University of Groningen did not come through, 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.[18]
Hahn and Meitner met clandestinely in Copenhagen in November to plan a new round of experiments, and they subsequently exchanged a series of letters. Hahn and Fritz Strassmann then performed the difficult experiments which isolated the evidence for nuclear fission at his laboratory in Berlin. The surviving correspondence shows that Hahn recognized that fission was the only explanation for the barium, but, baffled by this remarkable conclusion, he wrote to Meitner. The possibility that uranium nuclei might break up under neutron bombardment had been suggested years before, notably by Ida Noddack in 1934. However, by employing the existing "liquid-drop" model of the nucleus,[19] Meitner and Frisch were the first to articulate a theory of how 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). She and Frisch had discovered the reason that no stable elements beyond uranium (in atomic number) existed naturally; the electrical repulsion of so many protons overcame the strong nuclear force.[19] Meitner also first realized that Einstein's famous equation, E = mc2, explained the source of the tremendous releases of energy in nuclear fission, by the conversion of rest mass into kinetic energy, popularly described as the conversion of mass into energy.
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, had sparked the above inspiration in December 1938. Hahn claimed that his chemistry had been solely responsible for the discovery, although he had been unable to explain the results.
It was politically impossible for the exiled Meitner to publish jointly with Hahn in 1939. Hahn and Strassman had sent the manuscript of their paper to Naturwissenschaften in December 1938, reporting they had detected the element barium after bombarding uranium with neutrons;[20] simultaneously, they had communicated their results to Meitner in a letter. Meitner, and her nephew Otto Robert Frisch, correctly interpreted their results as being nuclear fission and published their paper in Nature.[21] Frisch confirmed this experimentally on 13 January 1939.[22]
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, Leó Szilárd, Edward Teller, and Eugene Wigner jumped into action, persuading Albert Einstein, a celebrity, to write President Franklin D. Roosevelt a letter of caution; this led eventually to the establishment several years later 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!"[23] Meitner said that Hiroshima had come as a surprise to her, and that she was "sorry that the bomb had to be invented."[24]
In Sweden, Meitner was first active at Siegbahn's Nobel Institute for Physics, and at the Swedish Defence Research Establishment (FOA) and the Royal Institute of Technology in Stockholm, where she had a laboratory and participated in research on R1, Sweden's first nuclear reactor. In 1947, a personal position was created for Meitner at the University College of Stockholm with the salary of a professor and funding from the Council for Atomic Research.[25]
Einstein himself respected Meitner and called her "our Marie Curie."[5]
On 15 November 1945 the Royal Swedish Academy of Sciences announced that Hahn had been awarded the 1944 Nobel Prize in Chemistry for the discovery of nuclear fission.[26] Some historians who have documented the history of the discovery of nuclear fission believe Meitner should have been awarded the Nobel Prize with Hahn.[27][28][29]
In 1966 Hahn, Fritz Strassmann and Meitner together were awarded the Enrico Fermi Award. On a visit to the USA in 1946 she received the honor of the "Woman of the Year" by the National Press Club dinner with President Harry Truman and others at the National Women's Press Club (USA) in January 1946, as well as many honorary doctorates and lectured at Princeton, Harvard and other US universities. Lise Meitner refused to move back to Germany, and enjoyed retirement and research in Stockholm until her late 80s. She received the Max Planck Medal of the German Physics Society in 1949. Meitner was nominated to receive the prize three times. An even rarer honour was given to her in 1997 when element 109 was named meitnerium in her honour.[5][30][31]
Meitner was elected a foreign member of the Royal Swedish Academy of Sciences in 1945, and had her status changed to that of a Swedish member in 1951.
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:
You all worked for Nazi Germany. And you tried to offer only a passive resistance. Certainly, to buy off your conscience you helped here and there a persecuted person, but millions of innocent human beings were allowed to be murdered without any kind of protest being uttered ... [it is said that] first you betrayed your friends, then your children in that you let them stake their lives on a criminal war – and finally that you betrayed Germany itself, because when the war was already quite hopeless, you did not once arm yourselves against the senseless destruction of Germany.—[32]
Hahn however wrote in his memoirs that he and Meitner had been lifelong friends.[33]
Meitner became a Swedish citizen in 1949. She finally decided to retire in 1960 and then moved to the UK where most of her relatives were, although she continued working part time and giving lectures. A strenuous trip to the United States in 1964 led to Meitner having a heart attack, which she spent several months recovering from. Her physical and mental condition weakened by atherosclerosis, she was unable to travel to the US to receive the Enrico Fermi prize and relatives had to present it to her. After breaking her hip in a fall and suffering several small strokes in 1967, Meitner made a partial recovery, but eventually was weakened to the point where she moved into a Cambridge nursing home. She died on October 27 at the age of 89. Meitner was not informed of the deaths of Otto Hahn and his wife Edith, as her family believed it would be too much for someone as frail as her to handle. [2] As was her wish, she was buried in the village of Bramley in Hampshire, at St. James parish church, close to her younger brother Walter, who had died in 1964. Her nephew Otto Robert Frisch composed the inscription on her headstone. It reads "Lise Meitner: a physicist who never lost her humanity."