Isaak Markovych Khalatnykov ( uk, Ісаа́к Ма́ркович Хала́тников; 17 October 1919 – 9 January 2021) was a leading

Soviet The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, it was nominally a federal union of fifteen national ...

theoretical physicist Theoretical physics is a branch of physics that employs mathematical models and abstractions of physical objects and systems to rationalize, explain and predict natural phenomena. This is in contrast to experimental physics, which uses experim ...

who has made significant contributions to many areas of

theoretical physics Theoretical physics is a branch of physics that employs mathematical models and abstractions of physical objects and systems to rationalize, explain and predict natural phenomena. This is in contrast to experimental physics, which uses experi ...

, including

general relativity General relativity, also known as the general theory of relativity and Einstein's theory of gravity, is the geometric theory of gravitation published by Albert Einstein in 1915 and is the current description of gravitation in modern physics. ...

quantum field theory In theoretical physics, quantum field theory (QFT) is a theoretical framework that combines classical field theory, special relativity, and quantum mechanics. QFT is used in particle physics to construct physical models of subatomic particles a ...

, as well as the theory of quantum liquids. He is well known for his role in developing the Landau-Khalatnikov theory of

superfluidity Superfluidity is the characteristic property of a fluid with zero viscosity which therefore flows without any loss of kinetic energy. When stirred, a superfluid forms vortices that continue to rotate indefinitely. Superfluidity occurs in two i ...

and the so-called BKL conjecture in the general theory of relativity.

Life and career

Isaak Khalatnikov was born into a Ukrainian Jewish family in Yekaterinoslav (now

Dnipro Dnipro, previously called Dnipropetrovsk from 1926 until May 2016, is Ukraine's fourth-largest city, with about one million inhabitants. It is located in the eastern part of Ukraine, southeast of the Ukrainian capital Kyiv on the Dnieper R ...

Ukraine Ukraine ( uk, Україна, Ukraïna, ) is a country in Eastern Europe. It is the second-largest European country after Russia, which it borders to the east and northeast. Ukraine covers approximately . Prior to the ongoing Russian invas ...

) and graduated from

Dnipropetrovsk State University Oles Honchar Dnipro National University (DNU, uk, Дніпровський національний університет імені Олеся Гончара) is an establishment of higher education in Dnipro, Ukraine. It was founded in 1918. ...

with a degree in Physics in 1941. He had been a member of the

Communist Party A communist party is a political party that seeks to realize the socio-economic goals of communism. The term ''communist party'' was popularized by the title of '' The Manifesto of the Communist Party'' (1848) by Karl Marx and Friedrich Engels. ...

since 1944. He earned his doctorate in 1952. His wife Valentina was the daughter of Revolutionary hero Nikolay Shchors. Much of Khalatnikov's research was a collaboration with, or inspired by,

Lev Landau Lev Davidovich Landau (russian: Лев Дави́дович Ланда́у; 22 January 1908 – 1 April 1968) was a Soviet-Azerbaijani physicist of Jewish descent who made fundamental contributions to many areas of theoretical physics. His a ...

, including the ''Landau-Khalatnikov theory'' of

. During 1969 he briefly worked as a part time professor of theoretical physics at Leiden University. In 1970, inspired by the mixmaster model introduced by Charles W. Misner, then at

Princeton University Princeton University is a private research university in Princeton, New Jersey. Founded in 1746 in Elizabeth as the College of New Jersey, Princeton is the fourth-oldest institution of higher education in the United States and one of the n ...

, Khalatnikov, together with

Vladimir Belinski Vladimir Alekseevich Belinski (last name is also spelled Belinsky, russian: Владимир Алексеевич Белинский; born 26 March 1941) is a Russian and Italian theoretical physicist involved in research in cosmology and general ...

and

Evgeny Lifshitz Evgeny Mikhailovich Lifshitz (russian: Евге́ний Миха́йлович Ли́фшиц; February 21, 1915, Kharkiv, Russian Empire – October 29, 1985, Moscow, Russian SFSR) was a leading Soviet physicist and brother of the physicist ...

, introduced what has become known as the BKL conjecture, which is widely regarded as one of the most outstanding open problems in the classical theory of gravitation. Khalatnikov directed the

Landau Institute for Theoretical Physics The L. D. Landau Institute for Theoretical Physics (russian: link=no, Институт теоретической физики имени Л. Д. Ландау (ИТФ)) of the Russian Academy of Sciences is a research institution, located in the s ...

Moscow Moscow ( , US chiefly ; rus, links=no, Москва, r=Moskva, p=mɐskˈva, a=Москва.ogg) is the capital and largest city of Russia. The city stands on the Moskva River in Central Russia, with a population estimated at 13.0 million ...

from 1965 to 1992. He was elected to the

Academy of Sciences of the Soviet Union The Academy of Sciences of the Soviet Union was the highest scientific institution of the Soviet Union from 1925 to 1991, uniting the country's leading scientists, subordinated directly to the Council of Ministers of the Soviet Union (until 1946 ...

in 1984. He has been awarded the

Landau Gold Medal The Landau Gold Medal (russian: Премия имени Л. Д. Ландау) is the highest award in theoretical physics awarded by the Russian Academy of Sciences and its predecessor the Soviet Academy of Sciences. It was established in 197 ...

, the

Humboldt Prize The Humboldt Prize, the Humboldt-Forschungspreis in German, also known as the Humboldt Research Award, is an award given by the Alexander von Humboldt Foundation of Germany to internationally renowned scientists and scholars who work outside of G ...

, and the Marcel Grossmann Award. He was also a foreign member of the

Royal Society of London The Royal Society, formally The Royal Society of London for Improving Natural Knowledge, is a learned society and the United Kingdom's national academy of sciences. The society fulfils a number of roles: promoting science and its benefits, re ...

. He was portrayed by actor Georg Nikoloff in the film '' The Theory of Everything''. Khalatnikov died in Chernogolovka on 9 January 2021, aged 101.Prominent Physicist Khalatnikov, Involved In Building 1st Soviet Nuclear Weapon, Dies
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Honours and awards

Order "For Merit to the Fatherland" The Order "For Merit to the Fatherland" (russian: Орден «За заслуги перед Отечеством», ''Orden "Za zaslugi pered Otechestvom"'') is a state decoration of the Russian Federation. It was instituted on 2 March 1994 by ...

, 3rd class *

Order of the October Revolution The Order of the October Revolution (russian: Орден Октябрьской Революции, ''Orden Oktyabr'skoy Revolyutsii'') was instituted on October 31, 1967, in time for the 50th anniversary of the October Revolution. It was conferr ...

* Order of the Patriotic War, 2nd class *

Order of the Red Banner of Labour The Order of the Red Banner of Labour (russian: Орден Трудового Красного Знамени, translit=Orden Trudovogo Krasnogo Znameni) was an order of the Soviet Union established to honour great deeds and services to the ...

, three times * Order of Friendship of Peoples *

Order of the Badge of Honour The Order of the Badge of Honour (russian: орден «Знак Почёта», orden "Znak Pochyota") was a civilian award of the Soviet Union. It was established on 25 November 1935, and was conferred on citizens of the USSR for outstanding ...

* Stalin Prize (1953)
Marcel Grossmann Award
(2012) "For the discovery of a general solution of the Einstein equations with a cosmological singularity of an oscillatory chaotic character known as the BKL singularity" * Asteroid 468725 Khalat was named in his honor. The official was published by the

Minor Planet Center The Minor Planet Center (MPC) is the official body for observing and reporting on minor planets under the auspices of the International Astronomical Union (IAU). Founded in 1947, it operates at the Smithsonian Astrophysical Observatory. Function ...

on 18 May 2019 ().

Partial bibliography

Books

* *

Selected academic works

* * * * * * * * * *

References

* * {{DEFAULTSORT:Khalatnikov, Isaak Markovich 1919 births 2021 deaths Communist Party of the Soviet Union members Foreign Members of the Royal Society Full Members of the Russian Academy of Sciences Full Members of the USSR Academy of Sciences Moscow Institute of Physics and Technology faculty Oles Honchar Dnipro National University alumni Recipients of the Order "For Merit to the Fatherland", 3rd class Recipients of the Order of Friendship of Peoples Recipients of the Order of the Red Banner of Labour Stalin Prize winners Jewish Russian scientists Men centenarians Russian centenarians Russian cosmologists Russian memoirists Russian physicists Soviet cosmologists Soviet physicists Superfluidity