Sakata Shōichi

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Japanese name: As is common in Japan, the family name comes before the first name in this article . So Sakata is the family name, Shōichi the first name.
Sakata Shōichi

Sakata Shōichi ( Japanese 坂 田 昌 一 ; * January 18, 1911 near Hiroshima ; † October 16, 1970 ) was a Japanese theoretical physicist.

Life

Sakata studied physics from 1929 to 1933 at the Imperial University of Tokyo with Yoshio Nishina and then at the Imperial University of Kyoto with Hideki Yukawa , with whom he started in 1937 (previously a year at the private research organization RIKEN , short for Rikagaku Kenkyūsho ) in Osaka, whose meson theory which developed nuclear forces (established by Yukawa in 1935). In 1939 he went with Yukawa to the University of Kyoto, where he was a lecturer. From 1942 he was a professor at Nagoya University , which he remained until the end of his life.

Sakata was the leading elementary particle theorist in Japan in the 1950s and 1960s. He founded a large school and one of his students was a. Yōichirō Nambu . He became known in the 1950s for his predecessor and model of the quark model of the hadrons , the Sakata model from 1956, which the group SU (3) also used, but instead of quarks as the basic building blocks of protons , neutrons and lambda particles (which has a strange Contains quark). According to the model, the neutral pion was composed of a proton and an anti-proton, for example. It was devised by Sakata to explain the Gell-Mann-Nishijima formula (1953) and used, for example, in the book by Harry Lipkin Lie Groups for Pedestrians . In 1960 he expanded his model with his colleagues at Nagoya University (including Z. Maki, M. Nakagawa, Y. Ōnuki) to the “Nagoya model”, which also included leptons . Even then, they developed a neutrino mixing matrix (there were first signs of a second type of neutrino in the early 1960s), a forerunner of the now accepted theory of neutrino oscillations . The Nagoya model was inspiration for the later Kobayashi-Masukawa matrix in the weak interaction that mixes the quark flavors and was introduced by Kobayashi and Toshihide Masukawa in 1973.

Sakata was a staunch Marxist and also politically active, a leader in the civil rights movement Jiyū Jinken Kyōkai (English Japan Civil Liberties Union ) and 1966 member of the Russell Tribunal . His Marxist philosophy of science was very influential in Japan. He was awarded the Asahi Prize in 1948 .

literature

  • M. Low: Shoichi Sakata: His life, the Sakata model and his achievements , Progress in theoretical Physics, Supplement, Vol. 167, 2007, pp. 1-8
  • Sakata, Scientific Works, Tokyo, Horei Printing Co., 1977
  • Shōichi Sakata, Mituo Taketani: Philosophical and methodological problems in physics . Akad.-Verl., Berlin 1982 (204 pages).
  • Jagdish Mehra, Helmut Rechenberg: The historical development of Quantum Theory , Vol. 6, Part 2, 1982

Web links

Individual evidence

  1. ↑ Yukawa, Sakata “On the interaction of elementary particles II”, Journal Physico-Mathematical Society of Japan, Vol. 19, 1937, p. 1084. They called the scalar mesons in it U-quanta.
  2. ↑ Mituo Taketani in: Shōichi Sakata, Mituo Taketani: Philosophical and methodological problems of physics . Akad.-Verl., Berlin 1982, p. 184 ff . (204 pp.).
  3. ↑ Sakata "On a composite model for the new particles", Progress of theoretical physics, Vol. 16, 1956, p. 686
  4. ↑ who were too young to be direct students of Sakata but were influenced by the Sakata school. When Sakata died, Kobayashi was still studying at his university in Nagoya.
personal data
SURNAME Sakata Shōichi
ALTERNATIVE NAMES 坂 田 昌 一 (Japanese)
BRIEF DESCRIPTION Japanese physicist
DATE OF BIRTH January 18, 1911
PLACE OF BIRTH at Hiroshima
DATE OF DEATH October 16, 1970