Biography:Yakov Borisovich Zel'dovich

Yakov Borisovich Zel'dovich
2014 stamp recognition of Yakov Borisovich Zel'dovich (1914–1987)
Born	8 March 1914 Minsk, Russian Empire (Present-day Belarus )
Died	2 December 1987(1987-12-02) (aged 73) Moscow, Soviet Union (Present-Day Russia )
Resting place	Novodevichy Cemetery, Moscow
Citizenship	Soviet Union
Alma mater	Saint Petersburg State University
Known for	Soviet atomic bomb project Hawking-Zel'dovich radiation Sunyaev–Zel'dovich effect Zel'dovich approximation Zel'dovich number ZND detonation model Shvab–Zel'dovich formulation Self-similar solution of the second kind Zel'dovich–Liñán model Harrison-Zel'dovich spectrum Zel'dovich mechanism Zel'dovich streaming Model Activation energy asymptotics Zeldovich pancake
Awards	Hero of Socialist Labor (1949,1954,1956)
Scientific career
Fields	Physics Combustion Astrophysics
Institutions	Institute of Chemical Physics Moscow State University Sternberg Astronomical Institute
Notable students	Rashid Sunyaev Roman Juszkiewicz Igor Dmitriyevich Novikov Sergei Kopeikin Sergei Shandarin Alexei Starobinsky Varun Sahni Mikhail Sazhin Vladimir M. Lipunov

Yakov Borisovich Zel'dovich ForMemRS (Belarusian: Я́каў Бары́савіч Зяльдо́віч, Russian: Я́ков Бори́сович Зельдо́вич; 8 March 1914 – 2 December 1987), also known as YaB, was a Soviet physicist of Belarusian Jewish ethnicity, who is known for his prolific contributions in cosmology and the physics of thermonuclear and hydrodynamical phenomena.

From 1943, Zel'dovich played a crucial role in the development of the Soviet Union's nuclear bomb project. In 1963, he returned to academia to embark on pioneering contributions on the fundamental understanding of the thermodynamics of black holes and expanding the scope of cosmology.

Biography

Early life and education

Yakov Zel'dovich was born into an ethnic Belarussian Jewish family in his grandfather's house in Minsk, Belarusian region in Russia, on 8 March 1914. However, in mid-1941, the Zel'dovich family moved to Leningrad (now St. Petersburg). They resided there until August 1941, when the family was evacuated together with the faculty of the Institute of Chemical Physics to Kazan to avoid the Axis Invasion of the Soviet Union. They remained in Kazan until the summer of 1943, when Zel'dovich moved to Moscow.

His father, Boris Naumanovich Zel'dovich, was a lawyer; his mother, Anna Petronova Zel'dovich (née Kiveliovich), a translator from French to Russian, was a member of the Writer's Union. Despite being born into a devoted and religious Jewish family, Zel'dovich was an "absolute atheist".

Zel'dovich was an autodidact. He did not earn a college degree or even attend college, but he was regarded as having a remarkably versatile intellect, and during his life he explored and made major contributions to a wide range of scientific endeavors. From a given opportunity in May 1931, he secured an appointment as a laboratory assistant at the Institute of Chemical Physics of the USSR Academy of Sciences, and remained associated with the institute for the remainder of his life. As a laboratory assistant, he received preliminary instructions on the topics involved in the physical chemistry and built up his reputation among his seniors at the Institute of Chemical Physics. Without having earned an undergraduate degree, he was allowed to attend the post graduate coursework at the Saint Petersburg State University due to upheavals that took place in educational infrastructure in Russia.

In 1936, he was successful in his candidacy for the Candidate of Science degree (a Soviet equivalent of PhD), having successfully defended his dissertation on the topic of the "adsorption and catalysis on heterogeneous surfaces". The centrality of his thesis focused towards the research on the Freundlich (or classical) adsorption isotherm, and Zel'dovich discovered the theoretical foundation of this empirical observation.

From 1932 to 1934, Zel'dovich attended the undergraduate courses on physics and mathematics at the Leningrad State University (now St. Petersburg State University), and later attended the technical lectures on introductory physics at the Leningrad Polytechnic Institute (now Peter the Great St. Petersburg Polytechnic University).

In 1939, Zel'dovich prepared his dissertation based on the mathematical theory of the physical interpretation of nitrogen oxidation, and successfully received the Doctor of Science on Physmatics when it was reviewed by Aleksandr A. Freiman. Zel'dovich discovered its mechanism, known in physical chemistry as the thermal NO
x mechanism or Zel'dovich mechanism.

Soviet atomic bomb program

Zel'dovich is regarded as one of the secret principals of the Soviet Union's nuclear weapons project, and his travels abroad were highly restricted to the Eastern Europe under close security by the Soviet Union. Soon after the discovery of nuclear fission by German chemist Otto Hahn in 1939, Russian physicists began investigating the spectrum of physics of fission and began hosting the seminars on that topic, extending the invitation to Igor Kurchatov and Yulii Khariton in 1940.

In May 1941, Zel'dovich worked with Yulii Khariton in achieving the constructed theory on theory of the kinetics of nuclear reactions in the presence of the critical conditions. The work of Khariton and Zel'dovich was extended towards the theories of ignition, combustion and detonation, that accounted for features not previously explained or correctly predicted features that had not yet been observed. The modern theory of detonation accordingly is called ZND theory (Zel'dovich-von Neumann-Dohring), and engaged the tedious work on fast neutron calculations but the work had delayed due to the German invasion of Soviet Union that disrupted the findings which were marked as classified in June 1941. In 1942, Zel'dovich was relocated to Kazan where he was tasked by the People's Commissariat of Munitions to carry out the work on the conventional gun powders to be supplied to the Soviet Army while Khariton was asked to design the new types of conventional weaponry.

In 1943, Joseph Stalin decided to launch the arms build-up of nuclear weapons, having given the charge to Igor Kurchatov who requested Stalin to relocate Zel'dovich and Khariton to Moscow for nuclear weapons program. Zel'dovich joined Igor Kurchatov's small team at the secretive laboratory in Moscow to launch the work on the nuclear combustion theory and became a head of the theoretical department at the Arzamas-16 in 1946.

Zel'dovich developed a scientific report with Isaak Gurevich, Isaak Pomeranchuk, and Khariton on the feasibility of releasing energy through nuclear fusion triggered by an atomic explosion and presented it to Igor Kurchatov. Zel'dovich had benefitted from physical and technical knowledge provided by German physicist Klaus Fuchs and American physicist Theodore Hall, who had worked on the American Manhattan Project to develop nuclear weapons.

In 1949, Zel'dovich led a team of physicists that conducted the first nuclear test, the RDS-1, based roughly on the American design obtained through the atomic spies in the United States , though he continued his fundamental work on explosive theory. Zel'dovich then began working on modernizing the successive designs of the nuclear weapon and initially conceived the idea of hydrogen bomb to Andrei Sakharov and others. In the course of his work on nuclear weapons, Zel'dovich did ground-breaking work in radiation hydrodynamics, and the physics of matter at high pressure.

Between 1950 and 1953, Zel'dovich performed calculations necessary for the feasibility of the hydrogen bomb that were verified by Andrei Sakharov, although the two groups worked in parallel on the development of the thermonuclear fusion. However, it was Sakharov that radically changed the approach to thermonuclear fusion, aided by Vitaly Ginzburg in 1952. He remained associated with the nuclear testings while heading the experimental laboratories at Arzamas-16 until October 1963, when he left for the academia.

Academia and Cosmology

In 1952, Zel'dovich began work in the field of elementary particles and their transformations. He predicted the beta decay of a pi meson. Together with S. Gershtein he noticed the analogy between the weak and electromagnetic interactions, and in 1960, he predicted the muon catalysis (more precisely, the muon-catalysed dt-fusion) phenomenon. In 1977, Zel'dovich together with Fyodor Shapiro was awarded the Kurchatov Medal, the highest award in nuclear physics of the USSR. The citation was "for prediction of characteristics of ultracold neutrons, their detection and investigation". He was elected academician of the USSR Academy of Sciences on 20 June 1958. He was a head of division at the Institute of the Applied Mathematics of the USSR Academy of Sciences from 1965 until January 1983.

Zel'dovich (right) with astrophysicist Iosif Shklovsky in 1977

In early 1960s, Zel'dovich started working in astrophysics and physical cosmology. In 1964, he and independently Edwin Salpeter were the first to suggest that accretion discs around massive black holes are responsible for the huge amounts of energy radiated by quasars. From 1965, he was a professor at the Department of Physics of the Moscow State University and a head of the division of Relativistic Astrophysics at the Sternberg Astronomical Institute. In 1966, he and Igor Novikov was the first to propose searching for black hole candidates among binary systems in which one star is optically bright and X-ray dark and the other optically dark but X-ray bright (the black hole candidate).

Zel'dovich worked 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 predicted, with Rashid Sunyaev, that the cosmic microwave background should undergo inverse Compton scattering. This is called the Sunyaev-Zel'dovich effect, and measurements by telescopes such as the Atacama Cosmology Telescope and the South Pole Telescope has established it as one of the key observational probes of cluster cosmology. Zel'dovich contributed sharp insights into the nature of the large scale structure of the universe, in particular, through the use of Lagrangian perturbation theory (the Zel'dovich approximation) and the application of the Burgers' equation approach via the adhesion approximation.

Black hole thermodynamics

Zel'dovich played a key role in developing the theory of black hole evaporation due to Hawking radiation. During Stephen Hawking's visit to Moscow in 1973, Soviet scientists Zel'dovich and Alexei Starobinsky showed Hawking that, according to the quantum mechanical uncertainty principle, rotating black holes should create and emit particles.

Publications

Books

• Zel'dovich Ya.B., Ruzmaikin A.A., (2015). Dynamo Problems in Astrophysics. Cambridge Scientific Publishers. ISBN 978-1908106445. 
• Zel'dovich Ya.B., Novikov I.D., (2014). Stars and Relativity. Dover. 
• Zel'dovich Ya.B., Raizer Yu.P., (2012). Physics of Shock Waves and High-Temperature Hydrodynamic Phenomena, Volume 1. Dover. 
• Zel'dovich Ya.B., Raizer Yu.P., (2012). Physics of Shock Waves and High-Temperature Hydrodynamic Phenomena, Volume 2. Dover. 
• Zel'dovich Ya.B., (1993). Selected Works of Yakov Borisovich Zeldovich: Particles, Nuclei, and the Universe. Princeton University Press. ISBN 978-0691087429. 
• Zel'dovich Ya.B., (1992). Selected Works of Yakov Borisovich Zeldovich: Chemical Physics and Hydrodynamics. Princeton University Press. ISBN 978-0691085944. 
• Zel'dovich Ya.B., (1992). My Universe:Selected Reviews. Routledge. ISBN 978-3718650040. 
• Zel'dovich Ya.B., Ruzmaikin A.A., Sokoloff D.D., (1990). Magnetic Fields in Astrophysics. Gordon & Breach Science Pub. ISBN 978-0677223308. 
• Zel'dovich Ya.B., Barenblatt G., Librovich V.B., Makhviladze G.M., (1985). The Mathematical Theory of Combustion and Explosions. Consultants Bureau. ISBN 978-0306109744. 
• Zel'dovich Ya.B., Pilipetsky N.F., Shukunov V.V., (1985). Principles of Phase Conjugation. Springer. ISBN 978-3-662-13573-0. 
• Zel'dovich Ya.B., Novikov I.D., (1983). Relativistic Astrophysics: The Structure and Evolution of the Universe vol 2. University of Chicago Press. ISBN 978-0226979571. 
• Zel'dovich Ya.B., Novikov I.D., (1971). Relativistic Astrophysics: Stars and Relativity vol 1. University of Chicago Press. ISBN 978-0226979557. 
• Zel'dovich Ya.B., Raizer Yu.P., (1968). Elements of Gasdynamics and the Classical Theory of Shock Waves. Academic Press. 
• Zel'dovich Ya.B., Kompaneets A.S., (1960). Theory of Detonation. Academic Press. 
• Zel'dovich Ya.B., Yaglom I.M., (1988). Higher mathematics for beginning physicists and engineers. Prentice Hall. ISBN 978-0133876482. 

Awards and honors

Igor Kurchatov called him a "genius" and Andrei Sakharov named him "a man of universal scientific interests." Stephen W. Hawking once said to Zel'dovich: "before I met you, I believed you to be a 'collective author', like Bourbaki."

• Dirac Medal of the ICTP (1985)
• Bruce Medal (1983)
• Gold Medal of the Royal Astronomical Society (1984).
• Kurchatov Medal (1977)
• Three times Hero of Socialist Labor (1949, 1953, 1957)
• Stalin Prize (1943, 1949, 1951, 1953)
• Lenin Prize (1957)
• Three Orders of Lenin (1949, 1962, 1974)
• Two Orders of the Red Banner of Labour (1945,1964)
• Order of the October Revolution (1962)
• An asteroid 11438 Zel'dovich was named in his honor in 2001 [1]

Further reading

• Overbye, D. Lonely Hearts of the Cosmos: The Scientific Quest for the Secret of the Universe. New York: HarperCollins, 1991.
• Annotated Bibliography for Yakov Borisovich Zel'dovich from the Alsos Digital Library for Nuclear Issues
• Yakov Borisovich Zel'dovich – page at the Moscow State University dedicated to Zel'dovich
• Theory of combustion of unmixed gases – Zel'dovich 1949, translated 1974