Zel’dovich, Yakov Borisovich

Yakov Borisovich Zel’dovich (March 8, 1914 ““ December 2, 1987) was a productive Soviet physicist. He was instrumental in the advancement of Soviet nuclear and thermonuclear weapons, and also was an invaluable assistance in the fields of adsorption and catalysis, shock waves, nuclear physics, particle physics, astrophysics, physical cosmology, and general relativity.

In 1914, he was born into a Jewish family in Minsk, now called Belarus. Four months after his birth, he and his family moved to St. Petersburg. They lived and worked there until August 1941, when Zel’dovich’s family along with the members of the institute where he was employed, were evacuated to Kazan to escape the Axis Invasion of the Soviet Union. They stayed in Kazan until the summer of 1943, at which time Zel’dovich moved to Moscow.

Zel’dovich was appointed a laboratory assistant at the Institute of Chemical Physics of the USSR Academy of Sciences in May 1931, at 17 years of age. He was associated all of his life with the Institute. He earned his Candidate of Science (equivalent to a PhD) based on his 1936 dissertation on adsorption and catalysis on heterogeneous surfaces. The most significant point of his dissertation was his research on classical adsorption isotherm. He is accredited with the theoretical foundation of this monumental observation. Zel’dovich received a Doctor of Science degree in Physics and Mathematics in 1939, with this dissertation based on oxidation of nitrogen. He discovered what is known as Thermal NO Mechanism or Zel’dovich Mechanism in physical chemistry.

Between 1937 and 1948 he studied much on the theory of ignition, combustion and detonation, with assistance from Julii Khariton. Together they accomplished significant results in the Theory of Nuclear Chain Reactions. He participated in the Soviet Atomic Project, developing nuclear weapons, from 1943 to October 1963.

The field of elementary particles and their transformations became an area of interest to him in 1952. The beta decay of a pi meson was one of his predictions. He worked with S. Gershtein to establish the analogy between the weak and electromagnetic interactions. In 1960, he predicted the muon catalysis phenomenon. The USSR awarded Fyodor Shapiro and Zel’dovich with the Kurchatov Medal, the highest honor in nuclear physics in USSR, for “prediction of characteristics of ultra cold neutrons, their detection and investigation.” On June 20, 1958, he was also nominated academician of the USSR Academy of Sciences. He served from 1968 until January of 1983, as head of division at the Institute of the Applied Mathematics of the USSR Academy of Sciences.

He focused a new effort in the early 1960s on astrophysics and physical cosmology. He was the first to suggest, along with another independently working physicist, that accretion discs around massive black holes are responsible for the huge amounts of energy radiated by quasars. Beginning in 1965, Zel’dovich also led a position as professor at Moscow State University in the Department of Physics. He was head of the division of Relativistic Astrophysics at the Sternberg Astronomical Institute. He was assistive on the theory of the evolution of the hot universe, the properties of the microwave background radiation, the large-scale structure of the universe, and the theory of black holes. He and Rashid Sunyaev predicted that the cosmic microwave background should undergo inverse Compton scattering, called Sunyaev-Zel’dovich effect. Measuring it is one of the largest observational efforts in cosmology.

Other great academicians have called him “genius” and “a man of universal scientific interests.”

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