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Yakov Borisovich ZeldovichForMemRS[1] (Russian:Я́ков Бори́сович Зельдо́вич,Belarusian:Я́каў Бары́савіч Зяльдо́віч; 8 March 1914 – 2 December 1987), also known asYaB,[2]D.S. was a leadingSovietphysicist ofBelarusian origin, who is known for his prolific contributions in physicalcosmology, physics ofthermonuclear reactions, combustion, andhydrodynamical phenomena.[3]
From 1943, Zeldovich, a self-taught physicist, started his career by playing a crucial role in the development of the formerSoviet program of nuclear weapons. In 1963, he returned to academia to embark on pioneering contributions on the fundamental understanding of thethermodynamics ofblack holes and expanding the scope of physical cosmology.[4]
Yakov Zeldovich was born into aBelarusian Jewish family in his grandfather's house inMinsk.[5] However, in mid-1914, the Zeldovich family moved toSaint Petersburg. They resided there until August 1941, when the family was evacuated together with the faculty of theInstitute of Chemical Physics toKazan to avoid theAxis Invasion of theSoviet Union.[6]: 301 They remained in Kazan until the summer of 1943, when Zeldovich moved to Moscow.[6]
His father, Boris Naumovich Zeldovich, was a lawyer; his mother, Anna Petrovna Zeldovich (née Kiveliovich), a translator from French to Russian, was a member of theWriter's Union.[6] Despite being born into a devoted and religious Jewish family, Zeldovich was an "absoluteatheist".[7][8]
Zeldovich was anautodidact. 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.[4] From a given opportunity in May 1931, he secured an appointment as a laboratory assistant at theInstitute of Chemical Physics of theAcademy of Sciences of the Soviet Union, and remained associated with the institute for the remainder of his life.[6][4]: 301 As a laboratory assistant, he received preliminary instructions on the topics involved in thephysical chemistry and built up his reputation among his seniors at the Institute of Chemical Physics.[6]: 301
From 1932 to 1934, Zeldovich attended the undergraduate courses on physics and mathematics at the Leningrad State University (nowSaint Petersburg State University), and later attended the technical lectures on introductory physics at the Leningrad Polytechnic Institute (nowPeter the Great St. Petersburg Polytechnic University).[6]: 301 [9]: 2–5
In 1936, he was successful in his candidacy for theCandidate of Science degree (a Soviet equivalent of PhD), having successfully defended his dissertation on the topic of the "adsorption andcatalysis on heterogeneous surfaces".[6]: 301 The centrality of his thesis focused towards the research on theFreundlich (or classical) adsorption isotherm, and Zeldovich discovered the theoretical foundation of this empirical observation.[1]
In 1939, Zeldovich prepared his dissertation based on the mathematical theory of the physical interpretation ofnitrogen oxidation, and successfully received theDoctor of Sciences inmathematical physics when it was reviewed byAlexander Frumkin.[10]: 39–40 Zeldovich discovered its mechanism, known inphysical chemistry as thethermalNOx mechanism orZeldovich mechanism.
Zeldovich is regarded as a secret principal of theSoviet nuclear weapons project; his travels abroad were highly restricted, to Eastern Europe, under close Soviet security.[11]: 198–199 Soon after the discovery ofnuclear fission (by German chemistOtto Hahn in 1939) Russian physicists had begun investigating the scope of nuclear-fission physics, and undertook seminars on that topic;Igor Kurchatov andYulii Khariton were engaged in 1940.[6]: 79–80
In May 1941, Zeldovich worked with Khariton in constructing a theory, on the kinetics of nuclear reactions in the presence of thecritical conditions.[6]: 81 The work of Khariton and Zeldovich was extended into theories of ignition,combustion anddetonation; these accounted for features which had not previously been correctly predicted, observed, nor explained.[6]: 82 [4] The modern theory of detonation accordingly is called theZeldovich-von Neumann-Dohring, or ZND, theory, and its development involved tediousfast neutron calculations; this work had been delayed, due to theGerman invasion of theSoviet Union, which obstructed progress on findings that in June 1941 would be de-classified.[6]: 82 In 1942, Zeldovich was relocated toKazan, and tasked by thePeople's Commissariat of Munitions to carry out work on conventionalgun powders to be supplied to theSoviet Army, while Khariton was asked to design the new types of conventional weaponry.[6]: 87–88
In 1943,Joseph Stalin decided to launch anarms build-up ofnuclear weapons, under the charge ofIgor Kurchatov; the latter requested Stalin to relocate Zeldovich and Khariton to Moscow, in the nuclear weapons program.[6]: 87–88 Zeldovich joinedIgor Kurchatov's small team at this secretive laboratory in Moscow to launch the work on the nuclear combustion theory, and became a head of the theoretical department at theArzamas-16 in 1946.[4]
WithIsai Gurevich [ru],Isaak Pomeranchuk, and Khariton, Zeldovich prepared a scientific report on the feasibility of releasing energy through nuclear fusion triggered by an atomic explosion, and presented it to Igor Kurchatov.[4] Zeldovich had benefitted from physical and technical knowledge provided by German physicistKlaus Fuchs and American physicistTheodore Hall, who each had worked on the AmericanManhattan Project to develop nuclear weapons.[6]: 89–90
In 1949, Zeldovich led a team of physicists that conducted the firstnuclear test, theRDS-1, based roughly on theAmerican design obtained through theatomic spies in the United States, though he continued his fundamental work on explosive theory.[6]: 89–90 Zeldovich then began working on modernizing the successivedesigns of thenuclear weapon and initially conceived the idea ofhydrogen bomb toAndrei Sakharov and others.[6]: 89–90 In the course of his work on nuclear weapons, Zeldovich did ground-breaking work in radiation hydrodynamics, and the physics of matter at high pressure.[citation needed]
Between 1950 and 1953, Zeldovich performed calculations necessary for the feasibility of thehydrogen bomb that were verified byAndrei 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 byVitaly Ginzburg in 1952.[12]: 56–57 He remained associated with the nuclear testing program, while heading the experimental laboratories atArzamas-16 until October 1963, when he left for academia.[10]: 38–40
In 1952, Zeldovich began work in the field ofelementary particles and their transformations. He predicted thebeta decay of api meson. Together withSemyon Gershtein he noticed the analogy between theweak andelectromagnetic interactions, and in 1960, he predicted themuoncatalysis (more precisely, the muon-catalysed dt-fusion) phenomenon. In 1977, Zeldovich together withFyodor Shapiro [ru] was awarded theKurchatov Medal, the highest award in nuclear physics of the Soviet Union. The citation was "for prediction of characteristics of ultracoldneutrons, 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 theInstitute of the Applied Mathematics of the USSR Academy of Sciences from 1965 until January 1983.[citation needed]
In early 1960s, Zeldovich started working inastrophysics andphysical cosmology. In 1964, he and independentlyEdwin Salpeter were the first to suggest thataccretion discs around massiveblack holes are responsible for the huge amounts of energy radiated byquasars.[13][14] From 1965, he was a professor at the Department of Physics of theMoscow State University and a head of the division ofRelativisticAstrophysics at theSternberg Astronomical Institute. In 1966, he andIgor Novikov were 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).[15]
Zeldovich worked on the theory of the evolution of the hot universe, the properties of themicrowave background radiation, thelarge-scale structure of the universe, and the theory ofblack holes. He predicted, withRashid Sunyaev, that the cosmic microwave background should undergo inverseCompton scattering. This is called theSunyaev-Zeldovich effect, and measurements by telescopes such as theAtacama Cosmology Telescope and theSouth Pole Telescope has established it as one of the key observational probes of cluster cosmology. Zeldovich contributed sharp insights into the nature of the large scale structure of the universe, in particular, through the use of Lagrangian perturbation theory (the Zeldovich approximation) and the application of the Burgers' equation approach via the adhesion approximation.[citation needed]
In 1974, in collaboration with A. G. Polnarev, suggested the existence of agravitational memory effect, for which a system of freely falling particles initially at relative rest are displaced after the passing of a burst ofgravitational radiation.[16]
Zeldovich played a key role in developing the theory ofblack hole evaporation due toHawking radiation. Zeldovich andCharles W. Misner concomitantly predicted the possibility of particle generation by rotatingKerr black holes in 1971, 1972. Previously, In 1965, Zeldovich had predicted that Kerr black holes would split the emission lines of photons as in a Zeeman effect. DuringStephen Hawking's visit to Moscow in 1973, Soviet scientists Zeldovich andAlexei Starobinsky showed Hawking that, according to the quantum mechanicaluncertainty principle,rotating black holes should create and emit particles.[17]
With his wife, Varvara Pavlovna Konstantinova, Yakov Zeldovich had a son and two daughters who were also physicists: son –Boris Zeldovich;[18] daughters – Olga Yakovlevna Zeldovich and Marina Yakovlevna Zeldovich.[citation needed]
Zeldovich also had a daughter, Annushka, with O.K. Shiryaeva.[19]
He had one more daughter in 1945, Alexandra Varkovitskaya, with a linguist and folkloristLudmila Varkovitskaya.[citation needed]
Zeldovich had another son with Nina Nikolaevna Agapova in 1958, whose name was Leonid Yakovlevich Agapov; he died in 2016 at the age of 58.[citation needed]
{{cite book}}: CS1 maint: multiple names: authors list (link){{cite book}}: CS1 maint: multiple names: authors list (link){{cite book}}: CS1 maint: multiple names: authors list (link){{cite book}}: CS1 maint: multiple names: authors list (link){{cite book}}: CS1 maint: multiple names: authors list (link)Igor Kurchatov called him a "genius" andAndrei Sakharov named him "a man of universal scientific interests." After the first meeting in Moscow,Stephen W. Hawking wrote to Zeldovich: "now I know that you are a real person and not a group of scientists likeBourbaki."[20] He was a member of theAmerican Academy of Arts and Sciences (1975),[21] the United StatesNational Academy of Sciences (1979),[22] and theAmerican Philosophical Society (1979).[23]
{{cite book}}: CS1 maint: multiple names: authors list (link)I think that you know me well enough: I am an absolute atheist, and all days of the week are completely the same to me.
Speaking about religion, Yakov Borisovich could say unambiguously, "I'm an absolute atheist".
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