Yuri Alexandrovich Krutkov (, 29 May 1890 – 12 September 1952) was a Russian and among the first Soviet theoretical physicists. Krutkov worked on cosmology, quantum theory, statistical mechanics, tensor fields, and other areas. He was a professor of physics at the

University of St. Petersburg Saint Petersburg State University (SPBGU; ) is a public research university in Saint Petersburg, Russia, and one of the oldest and most prestigious universities in Russia. Founded in 1724 by a decree of Peter the Great, the university from the be ...

from 1921-1952.

Life and work

Krutkov was born in

St. Petersburg Saint Petersburg, formerly known as Petrograd and later Leningrad, is the second-largest city in Russia after Moscow. It is situated on the River Neva, at the head of the Gulf of Finland on the Baltic Sea. The city had a population of 5,601, ...

where his father Alexander taught Greek, Latin and Russian. The family moved to

Lubny Lubny (, ) is a city in Poltava Oblast, central Ukraine. It serves as the administrative center of Lubny Raion. It also hosts the administration of , one of the hromadas of Ukraine. Population: History Lubny is reputed to be one of the oldes ...

for sometime. Krutkov graduated from the St. Petersburg gymnasium in 1908 and went to study physics at the University where he studied under

Paul Ehrenfest Paul Ehrenfest (; 18 January 1880 – 25 September 1933) was an Austrian Theoretical physics, theoretical physicist who made major contributions to statistical mechanics and its relation to quantum physics, quantum mechanics, including the theory ...

. He was among the first physicists who were purely theoretical. When Ehrenfest moved to Leiden University, he too did the same. His first work was on

adiabatic invariants A property of a physical system, such as the entropy of a gas, that stays approximately constant when changes occur slowly is called an adiabatic invariant. By this it is meant that if a system is varied between two end points, as the time for the ...

. Funded by a

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grant, he worked in Germany and Holland in 1922-23 during which time he met

Albert Einstein Albert Einstein (14 March 187918 April 1955) was a German-born theoretical physicist who is best known for developing the theory of relativity. Einstein also made important contributions to quantum mechanics. His mass–energy equivalence f ...

. Here he pointed out an error in Einstein's critique of

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's work on the expanding universe. Krutkov later considered rotational Brownian motion and looked at the theory of rolling motion of ships floating on a randomly moving sea and examined the physical predictions. He applied statistical mechanics to

gyroscopes A gyroscope (from Ancient Greek γῦρος ''gŷros'', "round" and σκοπέω ''skopéō'', "to look") is a device used for measuring or maintaining Orientation (geometry), orientation and angular velocity. It is a spinning wheel or disc in ...

and wrote a book on the general theory of gyroscopes in collaboration with

Alexei Krylov Aleksey Nikolaevich Krylov (; – October 26, 1945) was a Russian naval engineer, applied mathematician and memoirist. Biography Aleksey Nikolayevich Krylov was born on August 3 O.S., 1863 in Visyaga village near the town of Alatyr, Simbirsk ...

. Krutkov taught at the Leningrad Polytechnic Institute and at the Leningrad University where his students included V. A. Fock. During World War II he was imprisoned but continued to work on some aerodynamics problems with A.N. Tupolev.

References

{{DEFAULTSORT:Krutkov, Yuri Alexandrovich 1890 births 1952 deaths Russian physicists Academic staff of Saint Petersburg State University Scientists from Saint Petersburg