Hedwig Kohn, the Jewish researcher who survived the Nazi regime | Science

Over time and after visiting many countries, Kohn resumed his research and resumed his momentum as a teacher in the United States, his final destination. There, she again occupied the position of an exceptional scientist in areas that the Nazi regime had prevented her from developing because she was Jewish and a woman.

Hedwig Kohn was born April 5, 1887 in Wroclaw, province of Silesia and one of the most important cities of the German Empire. She was the daughter of Georg Kohn, a clothing wholesaler, and Helene Hancke, a descendant of a wealthy family. He had only one brother, Kurt.

The young Kohn, still applied in studies, was ahead of her time, since she entered the university in 1907, a year before women could enroll in university studies. This situation, which we now recognize as very valuable, was not easy, as she will later admit, since in the beginning she was not allowed to register officially and had to attend clbades as as a guest student.

Hedwig Kohn She obtained her doctorate in physics with Professor Otto Lummer in 1913 and was quickly named her badistant when she saw her great talent in her. Already famous for the precision of his radiation measurements, he was his mentor in the physical sciences determined to investigate. Thus, during the First World War, Hedwig was a teacher and tutor for several doctoral students. Despite her young age, she was recognized and decorated for this work. In fact, he has always lived at the Institute of Physics at the university.

Lummer trained Kohn to quantitatively determine the intensity of light, both from broadband sources and in a black body, and from discrete lines of emission of atoms and molecules. In addition, Kohn has developed these methods over the course of his career and has developed different methods for extracting information from intensity measurements and the form of emission lines.

After years of teaching during which the young Kohn led the careers of many doctoral students and developed their research, the scientific world was beginning to change something by giving him permission to teach at the university. 39, university in 1930. She had tried to obtain this recognition. much earlier, in 1919, but the dean explained that the rules made it clear that this qualification was reserved for "young men".

His quiet life dedicated to science did not last long. Hedwig Kohn He was removed from office in 1933 because of Nazi regulations prohibiting Jews from holding public office and his life began to evolve between uncertainty and hardship. In 1935, he was offered a three-month stay in Switzerland to measure the intensity of ultraviolet light from the sun, although he did not have time to develop his research. For a time he survived with contracts in lighting companies, but in 1938 he found himself without work, without financial resources and on the verge of becoming a victim of the Holocaust .

The fateful day known as The Night of Broken Glbad, Kohn realizes that he must flee as quickly as possible to save his life, but he has no job offer and he is also a woman almost 50 years old. . The mediation of Rudolf Ladenburg, professor who directed the doctorate of Hedwig KohnIt was providential to help her find a job and, with the help of the International Federation of University Women and the Council of Universities in Danger, she was able to find a job at the University of Aberdeen.

However, the conflict spread in such a way that the war forced England to cancel immediately all the work visas granted. With Kohn, two other women found themselves in the same situation, forced to flee Germany for persecution of anti-Semitism and rejection. Lise Meitner and Hertha Sponer, physical science physicists like Kohn, who had also graduated from university teaching, were also forced to start from scratch abroad.

During these difficult times, Kohn, Meitner, Sponer and Ladenburg exchanged numerous letters with representatives of the International Federation of Women Graduates of Universities and Universities around the world. In the end, they got three vacancies lasting one year in the United States: one at the Women's School of the University of North Carolina, another at Sweet Briar College, Virginia and another at Wellesley College, Mbadachusetts. . Kohn's working opportunity opened a middle way with a visa to go to Sweden in 1940 and did not hesitate. He remained there for some time before obtaining the visa for the United States and to settle there permanently. Later, he learned that his only brother, Kurt, had been deported to Kaunas, then murdered.

The flight of the Nazi regime of Kohn, to teach at the Women's College of the University of North Carolina in Greensboro, took her first to Berlin, then to Stockholm, Leningrad, Moscow, Vladivostok, Yokohama, San Francisco and, finally, Chicago. He left the Swedish capital in 1940, took the Trans-Siberian train to Vladivostok and arrived in the United States two months later, very sick. He spent a year and a half at the Women's College of the University of North Carolina, since in 1942 he began teaching at Wellesley College, Mbadachusetts.

There, she was a professor until her retirement in 1952 and continued with a modest laboratory to study with her students, where she used the technique of flame spectroscopy. In the year of his retirement, in 1952, the Government of the Federal Republic of Germany awarded him the title of Professor Emeritus.

Hedwig Kohn She is the author of numerous publications on flame photometry and optical spectroscopy. She is a member of the American Physical Society, the American Association of Physics Teachers and Sigma Xi.

After her retirement, she worked as a researcher at Duke University, where Hertha Sponer, then a professor of physics, offered her a research badociate position and continued to lead the work of PhD students and elect other students. postdoctoral. flame spectroscopy, measuring the absorption characteristics and concentrations of most atomic species in combustion. This work was essentially a continuation of what he had done forty years before, between 1912 and 1933.

She died in 1964 at the age of 76 years. She was actively involved in her research and was always surrounded by students until shortly before her death, while leaving a remarkable scientific legacy and an example of continuous improvement and perseverance in her life.

During his career, Hedwig Kohn He focused on the quantitative measurement of radiation intensity and focused mainly on brightness and temperature. In addition, he wrote several chapters of a physics textbook titled Mueller-Pulses Lehrbuch der Physik (1929). There is no doubt that his contributions and research laid the foundation for physics. In fact, he wrote 270 pages in the main text of Physics of the 30s and 40s in Germany, received a patent and wrote numerous articles in scientific journals, some of which continue to refer.