Yuri Alexandrovich Krutkov (russian: Юрий Александрович Крутков, 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 (SPBU; russian: Санкт-Петербургский государственный университет) is a public university, public research university in Saint Petersburg, Russia. Founded in 1724 by a de ...

from 1921-1952. Krutkov was born in

St. Petersburg Saint Petersburg ( rus, links=no, Санкт-Петербург, a=Ru-Sankt Peterburg Leningrad Petrograd Piter.ogg, r=Sankt-Peterburg, p=ˈsankt pʲɪtʲɪrˈburk), formerly known as Petrograd (1914–1924) and later Leningrad (1924–1991), i ...

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

Lubny Lubny ( uk, Лубни́, ), is a city in Poltava Oblast (province) of central Ukraine. Serving as the administrative center of Lubny Raion (district), the city itself is administratively incorporated as a city of oblast significance and does n ...

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 physicist, who made major contributions to the field of statistical mechanics and its relations with quantum mechanics, including the theory of phase transition an ...

. 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. Funded by a

Rockefeller Foundation The Rockefeller Foundation is an American private foundation and philanthropic medical research and arts funding organization based at 420 Fifth Avenue, New York City. The second-oldest major philanthropic institution in America, after the Carneg ...

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

Albert Einstein Albert Einstein ( ; ; 14 March 1879 – 18 April 1955) was a German-born theoretical physicist, widely acknowledged to be one of the greatest and most influential physicists of all time. Einstein is best known for developing the theory ...

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

Friedmann Friedman, Friedmann, and Freedman are surnames of German origin, and from the 17th century were also adopted by Ashkenazi Jews. It is the 9th most common surname in Israel (8th among Jews) and most common exclusively Ashkenazi name. They may refer ...

'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 and angular velocity. It is a spinning wheel or disc in which the axis of rotat ...

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