WHO WAS LISE MEITNER?

Lise MEITNER was an Austrian-Swedish physicist who while working with the German radiochemist Otto Hahn, was the first to identify they had inadvertantly achieved nuclear fission.

Lise Meitner was born in 1878 at 27 Kaiser Josefstrasse Vienna,Austria, the third child of Hedwig and Philipp Meitner. Kaiser Josefstrasse was an attractive tree-lined avenue that crossed Leopoldstadt from the commercial district at one end to the Prater, Vienna's huge park at the other. Her family was Jewish and she had eight brothers and sisters. The precise date of Meitner's birth is not clear. In the birth register of Vienna's Jewish Community it is shown as 17 November 1878 but on all other documents it is 7 November 1878. This was the date that Lise always used.

All of Lise's childhood was spent in Leopoldstadt. The town was situated just north across the Danube canal from the old city. Originally a ghetto it was called after Leopold I, who was responsible for expelling Vienna's Jews in the 1600s. Later, he reluctantly allowed them to return.

The number of Jews in the capital was to remained small for the next two centuries. However, this was to change. In the 1860s, residence restrictions were abolished and Jews from throughout the empire converged on Vienna and as a result Leopoldstadt grew.

The first three Meitner children, Gisela, Auguste (Gust)), and Lise, were born only a year apart. Lise was followed by: Moriz (Fritz), Carola (Lola), another boy, Frida, and finally Walter, the baby brother Lise adored, who was born in 1891.

Lise's father had a law practice and theirs' was essentially a middle class home. However with such a large family, luxuries were rare. These comprised mainly of a short summer breaks in the mountains, music lessons and a home stacked with books where all the children were encouraged to have enquiring minds. All of the family loved music but Gusti was by far the family's most talented musician. A child prodigy he became a composer and pianist of concert rank. From a young age Lisa was encouraged to play the piano, and her passion and love for music stayed with her all her life.

Despite their Jewish origins and living in an area dominated by Jewish people, it seems the family distanced itself from its Jewish past. Gusti's son, Otto Robert Frisch, later stated that his mother and all the Meitner children had been baptized and raised as Protestants. This has been disputed, as all the children were registered with the Jewish community at birth and only became baptised when they were adults--Lola and Gisela as Catholics in 1908, Lise as Protestant the same year. But the essence of Frisch's statement was true: the Meitners did leave the old religion for the new.

At school Lise's favourite subjects were mathematics and science, and she obtained good marks. By the time she was 13 she had completed as much education as a girl at this time could possibly achieve. Simply because women did not attend University.

However, changes were beginning and by the late 1890's women were being admitted to institutions of higher learning. So, having first completed her training to be a teacher Lise restarted her education in 1899 and then entered the University of Vienna in 1901.

The syllabus was heavy, filled with physics, chemistry, botany and calculus and took over twenty five hours of courses a week. Lectures bored her, but she was fascinated with the laboratory and as a result decided to pursue a career in physics. Meitner, studied analytical mechanics, electricity and magnetism, elasticity and hydronamics, acoustics, optics, thermodynamics and kinetic theory. Lise obtained inspiration from a theoretical physicist called Ludwig Boltzmann who believed that atoms were divisible.

In 1905 Meitner finished her undergraduate studies, and began her doctoral research.

The later suicide of her mentor, Ludwig Boltzmann only served to strengthen her determination to stick with physics and in 1905 she started working with radioactive elements. This was a new and chaotic field, but one that held a great deal of interest to Lise Meitner.

In 1906 Meitner began to work on the question of whether alpha particles are only absorbed as they pass through matter, or if they also scattered. Marie Curie had found some evidence of scattering in her research. Meitner continued this research, for its merits included new knowledge of alpha particles and proving that atoms are sources of intense electrical forces. She discovered a method of proving that the particles did indeed scatter. Alpha scattering would later lead to the discovery of the nuclear atom. Other scientific accomplishments of Lise Meitner include being the first to explain how conversion electrons were produced when gamma ray energy was used to eject orbital electrons, providing the first description of the origin of auger electrons (outer-shell orbital electrons ejected from the atom when they absorbed the energy released by other electrons falling to lower energy levels).

Her most significant accomplishment was published in 1939. She had discovered that when a uranium nucleus was struck by neutrons, barium was produced. This was strange because barium is so much smaller than uranium, and so another explanation was needed. She and her nephew Otto Frisch then used Niels Bohr's model of the nucleus to show the neutron inducing oscillations in the uranium nucleus. Sometimes the oscillating nucleus would stretch into a dumbbell shape. Also, sometimes the repulsive forces between the protons in the two rounded ends would cause the narrow waist in between to pinch off and leave two nuclei where there had only been one. Meitner described the process in a letter to the journal Nature and named it fission. She is also known for her work in atomic theory, and her prediction of the existence of chain reaction would lead to the discovery of the atomic bomb.

She became a visiting professor at Catholic University in Washington, D.C., and later returned to the United States and lectured at Bryn Mawr College.

Lise Meitner died in 1968.