Yukawa (Yukawa), Hideki( Japanese physicist, Nobel Prize in Physics, 1949)
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Biography Yukawa (Yukawa), Hideki
January 23, 1907, Mr.. - September 8, 1981
Japanese physicist Hideki Yukawa was born under the name of Hideki Ogawa in Tokyo, but after the marriage took the name of his wife - Yukawa, he was the fifth of seven children, and Takuji Ogawa Coyuca. A year after his birth the family moved to Kyoto, where his father was appointed Professor of Geology, Kyoto Imperial University.
Hideki grew up in the cultural and intellectual atmosphere. His father is actively interested in archeology, history and literature of ancient China and Japan. Another little boy Hideki met with the Chinese classics with the help of his paternal grandfather, philologist. In the 3rd school in Kyoto, . which he graduated in 1926, . he was interested in literature, . philosophy and mathematics, . but most of all attracted him to modern physics, . whom he had met, . reading books on the theory of relativity and quantum mechanics in Japanese, . available in the school library,
. He taught himself German, in order to read the original multi-volume edition of works of Max Planck, who bought it, rummaging through heaps of one of the bookshops.
. After school, Hideki entered Kyoto Imperial University, where he studied physics in an accelerated program and was distinguished by the fact that high-precision experiments conducted in the laboratory Kadzyuro Tamaki
. Having written a dissertation on the properties of the equation P.A.M. Dirac, where the theory of relativity apply to quantum mechanics to describe the motion of atomic particles, he received a master's degree in 1929. Hideki stayed in the laboratory Tamaki as an assistant without pay, but theoretical physics began to interest him more experimental. In Europe, conducted a most interesting work in the field of quantum theory, and the young physicist literally took over many of its unresolved problems. In his university courses quantum theory has been studied in a small volume, but between 1929 and 1932. He studied it yourself by reading the required literature. He spoke with Werner Heisenberg and Paul Dirac, when they arrived in Kyoto, and also met with Yoshio Nishino, who worked with Niels Bohr in Copenhagen. YU. confessed later, . Tamaki Nishino, and that had a decisive influence on his decision to devote himself to theoretical physics, . noting the absence of experimental tendencies and inability 'to master the production of ordinary glassware',
. In 1932, Mr.. He became a lecturer in physics at Kyoto University, one year later - in Osaka University, and in 1936. - Assistant professor in Osaka.
It was in Osaka SE. began to seriously ponder over the problem, . that the last two decades occupied the minds of physicists: why is the nucleus of an atom does not break into chastiN a while it was already known, . that the nucleus contains densely packed positively charged particles (protons),
. Since the same name electrical charges repel each other, and the repulsive force increases rapidly with decreasing distance between the charges, the coupling of protons seemed a mystery. Opening James Chadwick in 1932. neutron, an uncharged particle with a mass almost equal to the mass of the proton, even more complexities. Neutron soon recognized another inhabitant of the nucleus explained the existence of isotopes of elements with the same number of protons but different numbers of neutrons. However, the problem of the relationship of protons remained complicated by the need to explain the relationship of neutrons with each other and with protons. Gravity, the mutual attraction of all masses, too weak to exert considerable influence on the intranuclear clutch.
Several prominent physicists, including Heisenberg, offered his theory of the nucleus, but none of them could not stand criticism. It was clear that there is an unknown nuclear force, but it must be unusually strong and operate over short distances. Moreover, experts in quantum physics were bound to make known to consider force as a force acting through the exchange of particles containing a unit of energy force field, called quanta. In the case of the electromagnetic field of such a particle is a photon, the quantum of electromagnetic energy. There is no rest mass of photon - light or moves, or does not exist.
In 1935. YU. suggested that a large force holding the nucleus of the collapse is related to the exchange particle has a large mass. He published a complex but meaningful theory, which allowed him to calculate the mass (approximately 200 times the mass of an electron) of a hypothetical particle. He also showed that it is impossible to detect with conventional nuclear reactions, because of its large mass is equivalent to a very high energy, but could search the collision of cosmic rays with atomic nuclei.
Article S. appeared in the Japanese physical magazine. Although it was written in English, she spent two years remained unnoticed.
American physicist Carl D. Anderson discovered the positron in 1932, studying the photographs of tracks, obtained by passing cosmic rays through the ionization chamber. (Particles, . similar to, . that are present in cosmic rays, . invisible, . but electrify the water vapor in the chamber and forcing it to condense into visible droplets.) In 1937, . apparently unaware of the hypothesis of Yu, . Anderson, tracks discovered a previously unknown particle with mass, . similar to, . that was a hypothetical particle S,
. At first it was called mesons, and then meson (from the Greek 'meso' which means 'middle', as the mass of particles was intermediate between the masses of the electron and proton). This discovery brought fame to the prediction Yu, and Western physicists began to explore possible links. However, a few years later they realized that particles Anderson and S. - Is different particles. In particular, the observed meson weakly interacted with the nucleus (N. postulated that the strong interaction), and the time of his life was more than 100 times longer than the predicted one hundred millionth of a second. Some physicists began to suspect that Yu. went the wrong way.
S. returned to the Kyoto Imperial University in 1939. Since he was by then already well-known theorist, his presence helped the Physics Department of the University to receive international recognition. The Second World War interrupted the connection between Japanese and Western physicists, but S. continued his study of particles. In 1942, Mr.. Two of his staff, Yasutake Tanikawa and get off Sakata, suggested that there are two kinds of mesons, the heavier and lighter, and that Anderson has found an easier type of cosmic rays at sea level. It seems that the heavier particles S. can be detected only in the upper atmosphere, where the primordial cosmic rays for the first time interact with atomic nuclei. Then, the particle quickly breaks down into a lighter type of meson, increasing the lifetime of which allows them to reach lower altitudes.
In 1947, Mr.. Cecil F. Powell discovered the particle S. with an ionization chamber placed at high altitudes. Almost certainly he was not familiar with the work of Sakata and Tanikawa, but it seems he was known pion hypothesis proposed by Robert E. Marshak, and Hans A. Bethe in 1947. In 1948, Mr.. mesons were artificially produced in the laboratory of the University of California at Berkeley.
In connection with these discoveries, SW. was 'justified' and received in 1949. Nobel Prize in Physics "for his prediction of the existence of mesons on the basis of theoretical work on nuclear forces'. Particle S. became known as pi-meson, then simply peony. Easier particle Anderson called mu-meson, then the muon. In fact, peonies come in three types: one - is electrically neutral, the other carries a positive charge and the third negatively charged. It seems that the muons are almost identical to the electrons, except for their large mass. Were later found many other types of mesons.
When S. learned about the award, he was in the U.S., taking the previous year leave at Kyoto University to do research work at the Institute for Basic Research in Princeton (New Jersey). After a year in this institute, he accepted an invitation from Columbia University to work there a visiting professor. Financed its presence there since 1951, the University appointed him professor of physics. In 1953, Mr.. YU. returned to Kyoto University, occupying there the post of Director of the Research Institute for Fundamental Physics. Here he continued his research on quantum physics and elementary particles, as well as a lot of time to educate a whole generation of young Japanese physicists up to the resignation in 1970
. Since 1954, when the U.S. tested a thermonuclear weapon that devastated Bikini Atoll in the Pacific Ocean, SW
. became publicly speak out against nuclear weapons 'as a scientist, a Japanese and a representative of all mankind'. He was among the signatories 'Address Russell' (named after its author Bertrand Russell), who urged the government to solve their conflicts peacefully. YU. also participated in conferences at which scientists discussed the issues of disarmament.
S. (then Ogawa) married Sumi Yukawa in 1932. They raised two sons. In his last years he returned to the enthusiasms of his youth, became interested in history, literature and philosophy, and wrote poetry in Japanese. In addition to scientific papers, he published and philosophical reflections. In his book 'Creativity and intuition: look at the physics of East and West' ( 'Creativity and Intuition: A Physicist Loks at East and West', 1973) S. highly of the influence of Eastern philosophy, especially the Taoist philosopher Lao-tzu and Chuang-tzu, in his own way of thinking.
In addition to the Nobel Prize, SW. awarded the Imperial Prize of the Japan Academy of Sciences (1940), Gold Medal. Lomonosov USSR (1964), the Order of Merit of the Government of Germany (1967) and the Order of the Rising Sun - Japanese national award (1977). He was a member of dozens of prestigious scientific academies and societies, including the U.S. National Academy of Sciences, the Japan Physical Society, the Royal Society and the USSR.