Wolfgang Kroll (March 21, 1906 – February 28, 1992) was a physicist, born in Greifswald, northern Germany, who received his doctorate in physics from the University of Breslau in 1930. He spent the next few years in Leipzig conducting postdoctoral research with Werner Heisenberg.
Due to the power of the Nazi Party, Kroll left Germany in 1937 to teach in Hokkaido, Japan, and then arrived in the Japanese state of Taipei in 1941, where he taught at the Preparatory Department of the Imperial University of Taipei. After the war, Kroll was invited to transfer to the Department of Physics at National Taiwan University. He was promoted to Associate Professor and then to Professor. He was the first full-time professor in Taiwan to hold a doctorate in theoretical physics after the war. Afterward, he was invited to teach in the Physics Department of Tunghai University.
In August 1976, Kroll retired from the Department of Physics at National Taiwan University and became an honorary professor along with Xu Yunji the following year. After his retirement, Kroll also taught part-time at the Chinese Cultural University and other places. In the late 1970s, as Taiwan's economy began to take off, prices rose and Kroll's pension became relatively meagre, leaving him in a difficult position. On February 28, 1992, Kroll died of emphysema at National Taiwan University Hospital at the age of 87.
Life
Early years
Wolfgang Kröll was born on March 21, 1906, in Greifswald in the northern part of the German Empire. When he was a child, Kroll experienced the First World War, when Germany was short of supplies and the elephants in the zoo were shot and killed, leading Kroll to eat their flesh. In the late 1920s, Kroll entered the University of Breslau where he studied theoretical physics and received his Ph.D. physics from the university in 1930 with a thesis on Dirac's electron theory In the same year, he received a fellowship from the German Science Aid Organization and went to Leipzig University to do postdoctoral research under Werner Heisenberg for seven years. During this period, he also met Edward Teller, who would become the father of the hydrogen bomb, and between 1930 and 1937, Kroll published eight papers on quantum mechanics, magnetisation spectra, and thermoelectric effects, laying the foundation for his future independent research. After the Nazis gained power, Kroll often criticised current affairs. Although he was not Jewish, he was in danger because he was disliked by those in power. Therefore, with the help of his father and the university, Kroll began a solo exile to Japan in 1937. Kroll stated that he chose to go to Japan to see the "fascinating East" and that he and his father had many friends in Japan.
There are two accounts of the way Kroll left Germany. According to Xu Zhongping, Kroll exchanged with Shin'ichirō Tomonaga in Japan, while another theory suggests that Kroll's journey to Japan was arranged by his father. Kroll first went to London, England, and then to Japan via Shanghai, finally arriving in Hokkaido.
Travel to Japan
After arriving in Hokkaido, Kroll went to Hokkaido University, where he was a lecturer for five years beginning in 1937. At that time, he published three papers in five years with Tomonaga Shinichiro, who had just graduated from the physics department of Kyoto Imperial University, and also co-organized a course on quantum theory with Tomonaga. In 1937, with the support of Yoshio Nishina, Kroll published a paper on the theory of thermal conduction, and in 1941, he published a paper on the behaviour of free electrons in monovalent metals and their relation to specific heat. However, since the salary at the Hokkaido Imperial University was not high, Kroll took a part-time job as a teacher of German at a nearby commercial school. After the outbreak of World War II, Kroll left Hokkaido University to teach at the Institute of Physical and Chemical Research in Tokyo, and soon after left Japan to teach at Taipei Imperial University. At the end of 1941, Kroll arrived in Taiwan to teach at the Imperial University of Taipei. His salary was increased by 60%. However, the lecture system at that time did not allow Kroll to hold a lecture in physics, but only to teach German courses in the preparation and higher schools in Taipei. It was not until the end of the war that he began to teach physics. From April 20, 1945, all prep teachers and students, including Kroll, were engaged in position construction between Tamsui and Xinzhuang from that month onwards and were disbanded and reinstated after the war. He published a paper on mathematical physics in 1944 through the Proceedings of the Faculty of Science of the Imperial University of Taipei.