Editing Yakov Zeldovich (section)

==Biography==
===Early life and education===

Yakov Zeldovich was born into a [[History of the Jews in Belarus|Belarusian Jewish]] family in his grandfather's house in [[Minsk]].<ref name="Haaretz">{{cite web |work=[[Haaretz]]|url=http://www.haaretz.com/news/features/this-day-in-jewish-history/this-day-in-jewish-history-a-self-taught-nuclear-physicist-is-born-1.508640/|title=This day in Jewish history / A self-taught nuclear physicist is born|date= 8 March 2013 |access-date=8 November 2013}}</ref> However, in mid-1914, the Zeldovich family moved to [[Saint Petersburg]]. They resided there until August 1941, when the family was evacuated together with the faculty of the [[Institute of Problems of Chemical Physics|Institute of Chemical Physics]] to [[Kazan]] to avoid the [[Great Patriotic War|Axis Invasion]] of the [[Soviet Union]].<ref name="CRC Press Sunyaev">{{cite book |last1=Sunyaev |first1=Rashid |title=Zeldovich Reminiscences. |date=2004 |publisher=CRC Press |isbn=9780203500163 |edition=1 |location=London |pages=370 |language=en |chapter=Childhood and School days |author-link1=Rashid Sunyaev |access-date=17 April 2017 |chapter-url=https://books.google.com/books?id=JBAc8701A6wC&q=zel%27dovich+ceducation&pg=PA301}}</ref>{{rp|301}} They remained in Kazan until the summer of 1943, when Zeldovich moved to Moscow.<ref name="CRC Press Sunyaev"/><!--{{rp|xx}}-->

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 the [[Union of Soviet Writers|Writer's Union]].<ref name="CRC Press Sunyaev"/><!--{{rp|xx}}--> Despite being born into a devoted and religious Jewish family, Zeldovich was an "absolute [[Atheism|atheist]]".<ref>{{cite book|title=Zeldovich: Reminiscences|url=https://archive.org/details/zeldovichreminis00libg|url-access=limited|year=2004|publisher=CRC Press|isbn=9780415287906|author=Zel'dovich, Yakov Borisovich |editor=Sunyaev, R.A. |page=[https://archive.org/details/zeldovichreminis00libg/page/n95 69]|quote=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.}}</ref><ref>{{cite book|title=Andrei Sakharov: Facets of a Life|year=1991|publisher=Atlantica Séguier Frontières|isbn=9782863320969|page=599|quote=Speaking about religion, Yakov Borisovich could say unambiguously, "I'm an absolute atheist".}}</ref>

Zeldovich was an [[Autodidacticism|autodidact]]. 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.<ref name="nuclear weapon archives Sublette">{{cite web|last1=Sublette|first1=Carey|title=Yakov Zel'dovich|url=http://nuclearweaponarchive.org/Russia/Zeldovch.html|website=nuclearweaponarchive.org|publisher=nuclear weapon archives|access-date=17 April 2017|date=1 May 2002}}</ref> From a given opportunity in May 1931, he secured an appointment as a laboratory assistant at the [[Institute of Problems of Chemical Physics|Institute of Chemical Physics]] of the [[Academy of Sciences of the Soviet Union]], and remained associated with the institute for the remainder of his life.<ref name="CRC Press Sunyaev"/><ref name="nuclear weapon archives Sublette"/>{{rp|301}} 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.<ref name="CRC Press Sunyaev"/>{{rp|301}}

From 1932 to 1934, Zeldovich attended the undergraduate courses on physics and mathematics at the Leningrad State University (now [[Saint 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]]).<ref name="CRC Press Sunyaev"/>{{rp|301}}<ref name="American Institute of Aeronautics and Astronautics, Inc. Luca">{{cite book |last1=Sirignano |first1=W. |title=Advances in combustion science : in honor of Ya. B. Zel'dovich |last2=Merzhanov |first2=A. |last3=De Luca |first3=L. |date=1997 |publisher=American Institute of Aeronautics and Astronautics, Inc. |isbn=9781600864261 |edition=173 |location=Reston, Va. |pages=500 |language=en |chapter=Biography |access-date=18 April 2017 |chapter-url=https://books.google.com/books?id=vYQHMDKCQkQC&q=zel%27dovich+degree+1939&pg=PP17}}</ref>{{rp|2–5}}

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".<ref name="CRC Press Sunyaev"/>{{rp|301}} The centrality of his thesis focused towards the research on the ''Freundlich (or classical) adsorption isotherm'', and Zeldovich discovered the theoretical foundation of this empirical observation.<ref name="frs" />

In 1939, Zeldovich prepared his dissertation based on the mathematical theory of the physical interpretation of [[Nitrogen oxide|nitrogen oxidation]], and successfully received the [[Doctor of Sciences]] in [[mathematical physics]] when it was reviewed by [[Alexander Frumkin]].<ref name="Oxford University Press Hargittai">{{cite book|last1=Hargittai|first1=Istvan|title=Buried glory : portraits of Soviet scientists|date=2013|publisher=Oxford University Press|location=New York|isbn=9780199985593|pages=320|url=https://books.google.com/books?id=hWx4AAAAQBAJ&q=zel%27dovich+degree+1939&pg=PA39|access-date=18 April 2017|language=en}}</ref>{{rp|39–40}} Zeldovich discovered its mechanism, known in [[physical chemistry]] as the [[NOx#Thermal|thermal {{NOx}} mechanism]] or [[Zeldovich mechanism]].

===Soviet program of nuclear weapons===
{{main|Soviet atomic bomb program}}
Zeldovich is regarded as a secret principal of the [[Soviet atomic bomb project|Soviet nuclear weapons project]]; his travels abroad were highly restricted, to Eastern Europe, under close Soviet security.<ref name="Springer, Khalatnikov">{{cite book|last1=Khalatnikov|first1=Isaak M.|title=From the atomic bomb to the Landau Institute autobiography. Top non-secret|date=2012|publisher=Springer, Khalatnikov|location=Berlin|isbn=9783642275616|pages=210|url=https://books.google.com/books?id=5w09evl6wqYC&q=yakov+borisovich+zel%27dovich+nuclear+weapons&pg=PA198|access-date=18 April 2017|language=en}}</ref>{{rp|198–199}} Soon after the discovery of [[nuclear fission]] (by German chemist [[Otto Hahn]] in 1939) Russian physicists had begun investigating the scope of nuclear-fission physics, and undertook seminars on that topic; [[Igor Kurchatov]] and [[Yulii Khariton]] were engaged in 1940.<ref name="CRC Press Sunyaev"/>{{rp|79–80}}

In May 1941, Zeldovich worked with Khariton in constructing a theory, on the kinetics of nuclear reactions in the presence of the [[Critical mass|critical conditions]].<ref name="CRC Press Sunyaev"/>{{rp|81}} The work of Khariton and Zeldovich was extended into theories of ignition, [[combustion]] and [[detonation]]; these accounted for features which had not previously been correctly predicted, observed, nor explained.<ref name="CRC Press Sunyaev" />{{rp|82}}<ref name="nuclear weapon archives Sublette" /> The modern theory of detonation accordingly is called the [[ZND detonation model|Zeldovich-von Neumann-Dohring, or ZND, theory]], and its development involved tedious [[fast neutron calculations]]; this work had been delayed, due to the [[Operation Barbarossa|German invasion]] of the [[Soviet Union]], which obstructed progress on findings that in June 1941 would be de-classified.<ref name="CRC Press Sunyaev"/>{{rp|82}} In 1942, Zeldovich was relocated to [[Kazan]], and tasked by the [[Ministry of Agricultural Machine Building|People's Commissariat of Munitions]] to carry out work on conventional [[Gunpowder|gun powders]] to be supplied to the [[Soviet Army]], while Khariton was asked to design the new types of conventional weaponry.<ref name="CRC Press Sunyaev"/>{{rp|87–88}}

In 1943, [[Joseph Stalin]] decided to launch an [[Nuclear arms race|arms build-up]] of [[Russia and weapons of mass destruction|nuclear weapons]], under the charge of [[Igor Kurchatov]]; the latter requested Stalin to relocate Zeldovich and Khariton to Moscow, in the nuclear weapons program.<ref name="CRC Press Sunyaev" />{{rp|87–88}} Zeldovich joined [[Igor 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 the [[Arzamas 16|Arzamas-16]] in 1946.<ref name="nuclear weapon archives Sublette" />

With [[Isaak Gurevich]], [[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.<ref name="nuclear weapon archives Sublette" /> Zeldovich had benefitted from physical and technical knowledge provided by German physicist [[Klaus Fuchs]] and American physicist [[Theodore Hall]], who each had worked on the American [[Manhattan Project]] to develop nuclear weapons.<ref name="CRC Press Sunyaev"/>{{rp|89–90}}

In 1949, Zeldovich led a team of physicists that conducted the first [[nuclear test]], the [[RDS-1]], based roughly on the [[Fat Man|American design]] obtained through the [[atomic spies]] in the United States, though he continued his fundamental work on explosive theory.<ref name="CRC Press Sunyaev" />{{rp|89–90}} Zeldovich then began working on modernizing the successive [[Nuclear weapon design|designs]] of the [[nuclear weapon]] and initially conceived the idea of [[hydrogen bomb]] to [[Andrei Sakharov]] and others.<ref name="CRC Press Sunyaev"/>{{rp|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|date=May 2023}}

Between 1950 and 1953, Zeldovich performed calculations necessary for the feasibility of the [[Thermonuclear weapon|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.<ref name="Springer, Roberg">{{cite book|last1=Roberg|first1=Jeffrey L.|title=Soviet Science under Control: The Struggle for Influence| date=1998| publisher=Springer| location=U.S.|isbn=9781349262908|pages=153|edition=1|chapter-url=https://books.google.com/books?id=zTS_DAAAQBAJ&q=zel%27dovich+hydrogen+bomb+1949&pg=PA56|access-date=18 April 2017|language=en|chapter=The Hydrogen Bomb}}</ref>{{rp|56–57}} He remained associated with the nuclear testing program, while heading the experimental laboratories at [[Arzamas]]-[[Arzamas 16|16]] until October 1963, when he left for academia.<ref name="Oxford University Press Hargittai"/>{{rp|38–40}}