Ilya Mikhailovich Lifshitz (russian: Илья́ Миха́йлович Ли́фшиц; January 13, 1917 – October 23, 1982) was a leading Soviet theoretical

physicist A physicist is a scientist who specializes in the field of physics, which encompasses the interactions of matter and energy at all length and time scales in the physical universe. Physicists generally are interested in the root or ultimate cau ...

, brother of

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 ...

. He is known for his works in solid state physics, electron theory of metals, disordered systems, and the theory of

polymers A polymer (; Greek '' poly-'', "many" + ''-mer'', "part") is a substance or material consisting of very large molecules called macromolecules, composed of many repeating subunits. Due to their broad spectrum of properties, both synthetic an ...

Work

Ilya Lifshitz was born into a

Ukrainian Jewish The history of the Jews in Ukraine dates back over a thousand years; Jewish communities have existed in the territory of Ukraine from the time of the Kievan Rus' (late 9th to mid-13th century). Some of the most important Jewish religious and ...

family in Kharkov,

Kharkov Governorate The Kharkov Governorate ( pre-reform Russian: , tr. ''Khárkovskaya gubérniya'', IPA: �xarʲkəfskəjə ɡʊˈbʲernʲɪjə ) was a governorate of the Russian Empire founded in 1835. It embraced the historical region of Sloboda Ukraine. Fro ...

Russian Empire The Russian Empire was an empire and the final period of the Russian monarchy from 1721 to 1917, ruling across large parts of Eurasia. It succeeded the Tsardom of Russia following the Treaty of Nystad, which ended the Great Northern War. ...

(now

Kharkiv Kharkiv ( uk, wikt:Харків, Ха́рків, ), also known as Kharkov (russian: Харькoв, ), is the second-largest List of cities in Ukraine, city and List of hromadas of Ukraine, municipality in Ukraine.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 inv ...

). Together with Arnold Kosevich, in 1954 Lifshitz established the connection between the oscillation of magnetic characteristics of metals and the form of an electronic surface of Fermi ( Lifshitz–Kosevich formula) from de Haas–van Alphen experiments. Lifshitz was one of the founders of the theory of disordered systems. He introduced some of the basic notions, such as

self-averaging A self-averaging physical property of a disordered system is one that can be described by averaging over a sufficiently large sample. The concept was introduced by Ilya Mikhailovich Lifshitz. Definition Frequently in physics one comes across si ...

, and discovered what is now called Lifshitz tails and

Lifshitz singularity Lifshitz (or Lifschitz) is a surname, which may be derived from the Polish city of Głubczyce (German: Leobschütz). The surname has many variants, including: , , Lifshits, Lifshuts, Lefschetz; Lipschitz (Lipshitz), Lipshits, Lipchitz, Lipschutz ( ...

. In

perturbation theory In mathematics and applied mathematics, perturbation theory comprises methods for finding an approximate solution to a problem, by starting from the exact solution of a related, simpler problem. A critical feature of the technique is a middl ...

, Lifshitz introduced the notion of

spectral shift function ''Spectral'' is a 2016 3D military science fiction, supernatural horror fantasy Fantasy is a genre of speculative fiction involving magical elements, typically set in a fictional universe and sometimes inspired by mythology and f ...

, which was later developed by

Mark Krein Mark Grigorievich Krein ( uk, Марко́ Григо́рович Крейн, russian: Марк Григо́рьевич Крейн; 3 April 1907 – 17 October 1989) was a Soviet mathematician, one of the major figures of the Soviet school of fu ...

. A phase transition involving topological changes of the material's

Fermi surface In condensed matter physics, the Fermi surface is the surface in reciprocal space which separates occupied from unoccupied electron states at zero temperature. The shape of the Fermi surface is derived from the periodicity and symmetry of the crys ...

is called a Lifshitz phase transition. Starting from the late 1960s, Lifshitz started considering problems of statistical physics of polymers. Together with his students Alexander Yu. Grosberg and Alexei R. Khokhlov, Lifshitz proposed a theory of coil-to-globule transition in homopolymers and derived the formula for the conformational entropy of a polymer chain, that is referred to as the Lifshitz entropy. Some problems of the statistical physics of polymer chains with volume interaction. I. M. Lifshitz, A. Yu. Grosberg, and A. R. Khokhlov. ''Rev. Mod. Phys.'' 1978, 50, 683. https://journals.aps.org/rmp/abstract/10.1103/RevModPhys.50.683

References

External links

Page at KPI

1917 births 1982 deaths Scientists from Kharkiv People from Kharkov Governorate Ukrainian Jews Jewish physicists Full Members of the USSR Academy of Sciences Foreign associates of the National Academy of Sciences Soviet Jews Soviet physicists Theoretical physicists National University of Kharkiv alumni Kharkiv Polytechnic Institute alumni National University of Kharkiv academic personnel Burials at Kuntsevo Cemetery {{Russia-physicist-stub