Lise Meitner was a renowned Austrian scientist who was a part of the team led by Otto Hahn that discovered nuclear fission in uranium. Her discovery of the phenomenon where the heavier uranium nucleus disintegrates to form lighter nucleus, heralded a new era in the world of nuclear physics.
Background
Lise Meitner was born on November 7, 1878, into a relatively wealthy, cultured family in Vienna, capital of the Austro-Hungarian Empire.
Her father was Philipp Meitner, a lawyer, and chess master. Her mother was Hedwig Skovran, a talented amateur musician. Lise was the third of the couple's eight children.
Education
Even as a child Lise was academically inclined. She enjoyed mathematics, and her father employed private tutors to help her learn more. She also enjoyed playing the piano, reading, and finding out how the world worked. Her parents encouraged all their children to think independently. Her mother told them: "Listen to your father and me, but think for yourself."
Lise was a serious child for whom, like all Austrian girls in the 1800s, formal schooling ended at age 14. Unlike her brothers, she was not permitted to attend a grammar school to prepare for a college education.
Lise stayed at home, read books, and played piano. She eventually asked her father if she could take a science degree at the University of Vienna. Her father was sympathetic, but knew it would not be easy.
He recommended that Lise get a teaching qualification first so she could stand on her own two feet. Lise began working for a teaching qualification in French, which she completed in 1899, age 21. Her father then paid for private tutoring to help her prepare for the university entrance exam, which she passed in the summer of 1901.
Lise Meitner matriculated at the University of Vienna in October 1901. She was 22 years old and had decided to major in physics. Soon she found herself inspired by the brilliant Ludwig Boltzmann. Almost all her physics classes were taught by Boltzmann, and Meitner held him in the highest esteem.
In December 1905, Meitner passed her doctoral oral exam summa cum laude (the highest honor) and, in February 1906, graduated with a doctoral degree in physics.
Her doctoral thesis was entitled: Thermal Conduction in Non-homogeneous Bodies. Unsure what to do next, Meitner wrote Marie Curie asking for a research position in her Paris laboratory, but unfortunately, no work was available.
After her doctoral studies, Lise Meitner moved to Berlin and there she collaborated with chemist Otto Hahn. The duo embarked on a study of radioactivity and discovered a new element, which was named protactinium, in the year 1918.
This genius mind then discovered the phenomenon of radiationless transition which occurs when an electron from higher energy level fills in the vacuum created by a core electron leaving the atom leading to the liberation of energy. The transfer of energy can occur in the form of another electron leaving the same atom. This phenomenon where a secondary electron is released from the atom is named as the Auger Effect.
Though she discovered the phenomenon in 1923, it was named after another scientist Pierre Victor Auger who arrived at these conclusions about two years later. It was one of the many instances where Lise had to suffer the consequences of being a woman.
She was then offered a position of professor, at the University of Berlin in 1926. Her appointment as the head of the physics department of the Kaiser Wilhelm Institute for Chemistry, earned her the distinction of becoming the first woman professor in Germany.
At Berlin, she continued her association with Hahn and the duo started the ‘transuranium research program’ in 1935. After Austria's annexation, three years later, she moved to Sweden in order to escape from German oppression.
Despite all odds, she continued her research on the transuranium program at Nobel Institute in Stockholm. She met Hahn in Copenhagen where they decided to conduct several experiments. Their efforts bore fruition when they observed the phenomenon of nuclear fission in uranium for the first time during 1938-1939.
Meitner's nephew Otto Frisch worked in Copenhagen at the Niels Bohr Institute and the two set about explaining the phenomenon of fission observed in uranium which produced a lighter element when bombarded with neutrons. Their findings were published in the scientific journal Nature.
The discovery of nuclear fission had a great impact on the scientific community and they started pondering the different ways in which the energy released during atomic disintegration can be harnessed. Various scientific groups started exploring the possibility of creating an atomic bomb.
This eminent scientist then worked with several government agencies including the Swedish Defence Research Agency and Royal Institute of Technology. During this time she was involved with the development of a nuclear reactor in Sweden.
In 1947, she was honored by the University College of Stockholm which granted her a personal position at the institution, and her research work was funded by the Council for Atomic Research.
She stayed in Stockholm till 1960, when she retired and moved to Cambridge, where most of her relatives resided.
In 1946, Lise Meitner was named "Woman of the Year" by the National Press Club of the United States. The German Physical Society presented her with the Max Planck Medal, in 1949, for her contribution to nuclear physics. Meitner was the first recipient of the Otto Hahn Prize presented by the German Chemical Society in 1955. The highest German order granted to a scientist, the peace class of the Pour le Mérite, was conferred upon her in the year 1957. The award was presented to her by German President Theodor Heuss.
The Meitner family were non-religious Jewish. Later in life, they converted to Christian denominations. At the age of 29, Lise became a Lutheran.
Views
In December 1938, Hahn and Strassmann, continuing their experiments bombarding uranium with neutrons, found what appeared to be isotopes of barium among the decay products. They couldn’t explain it, since it was thought that a tiny neutron couldn't possibly cause the nucleus to crack in two to produce much lighter elements. Hahn sent a letter to Meitner describing the puzzling finding.
Over the Christmas holiday, Meitner had a visit from her nephew, Otto Frisch, a physicist who worked in Copenhagen at Niels Bohr's institute. Meitner shared Hahn's letter with Frisch. They knew that Hahn was a good chemist and had not made a mistake, but the results didn't make sense. They went for a walk in the snow to talk about the matter, Frisch on skis, Meitner keeping up on foot. They stopped at a tree stump to do some calculations. Meitner suggested they view the nucleus like a liquid drop, following a model that had been proposed earlier by the Russian physicist George Gamow and then further promoted by Bohr. Frisch, who was better at visualizing things, drew diagrams showing how after being hit with a neutron, the uranium nucleus might, like a water drop, become elongated, then start to pinch in the middle, and finally split into two drops.
After the split, the two drops would be driven apart by their mutual electric repulsion at high energy, about 200 MeV, Frisch and Meitner figured. Where would the energy come from? Meitner determined that the two daughter nuclei together would be less massive than the original uranium nucleus by about one-fifth the mass of a proton, which, when plugged into Einstein’s famous formula, E=mc2, works out to 200 MeV. Everything fit.
Frisch left Sweden after Christmas dinner. Having made the initial breakthrough, he and Meitner collaborated by long-distance telephone. Frisch talked briefly with Bohr, who then carried the news of the discovery of fission to America, where it met with immediate interest.
Meitner and Frisch sent their paper to Nature in January. Frisch named the new nuclear process "fission" after learning that the term "binary fission" was used by biologists to describe cell division. Hahn and Strassmann published their finding separately and did not acknowledge Meitner’s role in the discovery.
Scientists quickly recognized that if the fission reaction also emitted enough secondary neutrons, a chain reaction could potentially occur, releasing enormous amounts of energy. Many scientists joined the efforts to produce an atomic bomb, but Meitner wanted no part of that work and was later greatly saddened by the fact that her discovery had led to such destructive weapons. She did continue her research on nuclear reactions and contributed to the construction of Sweden's first nuclear reactor. Hahn won the Nobel Prize in chemistry in 1944, but Meitner was never recognized for her important role in the discovery of fission.
Membership
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. Four years later she was elected a Foreign Member of the Royal Society (ForMemRS). She was elected a Foreign Honorary Member of the American Academy of Arts and Sciences in 1960.
Meitner received 21 scientific honors and awards for her work (including 5 honorary doctorates and membership of 12 academies). In 1947 she received the Award of the City of Vienna for science. She was the first female member of the scientific class of the Austrian Academy of Sciences. In 1960, Meitner was awarded the Wilhelm Exner Medal and in 1967, the Austrian Decoration for Science and Art.
The Royal Swedish Academy of Sciences
1945
The Royal Society
1956
American Academy of Arts and Sciences
1960
Austrian Academy of Sciences
Personality
Physical Characteristics:
Towards the end of her life, Lise suffered from atherosclerosis which deteriorated her mental condition, and in 1964 during a trip to the United States, she had a heart attack, which caused further complications.
Nursing a broken hip and several minor heart attacks, this eminent physicist breathed her last on 27 October, 1968 and she was interred in Hampshire.
Interests
Walking, concerts
Connections
Meitner lived her life in the service of science. She never married and had no children.