Landau, Lev Davidovich

views updated Jun 11 2018

Landau, Lev Davidovich

(b. Baku, Russia, 22 January 1908; d. Moscow, U.S.S.R, 3 April 1968)

theoretical physics.

Landau’s father was a well-known petroleum engineer who had worked int he Baku oil fields. His mother received a medical education in St. Petersburg, where she did scientific work in physiology and later worked as a physician. When Landau finished school at thirteen, he was already attracted to the exact sciences. His parents though him too too young to enter Baku University (now Kirov Azerbaydzhan State Universty), where he studied in the department of physics-mathematics adn chemistry. Although Landau did not continue his chemical education, he retained an interest in chemistry until his death.

In 1924 he transferred to the physics department of Leningrad University; three years later he published his first scientific work, on quantum mechanics. Also in 1927 he graduated from the university and became a graduate student at the Leningrad institute of Physics and Technology. In his work devoted to Bremsstrahlung Landau first introduced the quantity later known as the density matrix (1927).

In 1929 Landau visited Germany, Switzerland, Holland, England, Belgium, and Denmark. There he became acquainted with Hohr, Pauli, Ehrenfest, and W. Heisenberg. Most important for Landau was his work in Copenhagen where theoretical physicists from Europe had gathered around Bohr. His participation in Bohr’s seminar played an improtant role in Landau’s development as a theoretical physicist. In 1930 Landau together with R. Peierls investigated a number of subtle problems in quantum mechanics. In the same year Landau did fundamental work in the field of the theory of metals, showing that the degenerate electron gas possesses diamagnetic susceptibility (Landau diamagnetism).

In 1931 he returned to Leningrad and worked int he Institute of Physics adn Technology; in 1932 he transferred to Kharkov, where he became the scientific leader of the theoretical group of the newly created Ukrainian Institute of Physics adn Technology. At the same time he occupied the chair of theoretical physics at the Kharkov Institute of Mechanical Engineering, and from 1935 he occupied the chair of general physics at Kharkov University.

In 1934 he ws awarded the degree of Doctor of Physical and Mathematical Sciences without defending a dissertation, and in 1935 he received the title of professor. The foundation for his creation of a extensive Soviet school of theoretical physics ws laid at Kharkov.

Landau’s scientific work during this period dealt with various problems in the physics of solid bodies, the theory of atomic collisions, nuclear physics, astrophysics, general questions of thermodynamics, quantum electrodynamics, the kinetic theory of gases, and the theory of chemical reactions. Especially noteworthy is his well-known work on the kinetic equation for the case of Coulomb interactions, the theory of ferromagnetic domain structure adn ferromagnetic resonance, the theory of the anti ferromagnetic state, the statistical theory of nuclei, and the widely known theory of second-order phase transitions.

In 1937 Landau became director of the section of theoretical physics of the Institute of Physical problems of the U.S.S.R. Academy of Sciences in Moscow, where he worked until the end of his life.

Landau’s scientific work from 1937 to 1941 dealt especially with the cascade theory of electron showers adn the intermediate state of superconductors. The physics of elementary particles adn nuclear interactions began to occupy an ever greater place in his works. In 1941 he elaborated the basic features of the theory of the super fluidity of helium II. His work in the physics of combustion and the theory of explosions (1944–1945) is noteworthy, as is his research on the scattering of protons by protons and on the theory of protons by protons and on the theory of ionization losses of fast particles in a medium. In 1946 Landau developed the theory of electron plasma oscillations.

From 1947 to 1953 Landau considered various questions in electrodynamics, teh theory of viscosity of helium II, the new phenomenological theory of superconductivity and, the theory, of great importance in the physics of cosmic rays, of the multiple origin of particles in the collision of fast particles.

In 1954 Landau studied questions dealing with the principle of the quantum field theory. As a result of this work, in 1955 he and I. Y. Pomeranchuk obtained a significant argument suggesting that the perturbation series of quantum electrodynamics and the quantum field theory of strong interactions do not sum to a consistent solution.

From 1956 to 1958 Landau created a general theory of the so-called Fermi-liquid, to which liquid helium III and the electrons in metals are related. In 1957 he presented a new general law of modern physics, the law of CP conservation, to replace the law of the conservation of parity which appeared incorrect for weak interactions. In 1959 Landu advanced new principles of the structure of the theory of elementary particles. In a published article he noted a way to determine the basic properties of the so-called interaction amplitude of particles.

Landau’s published textbooks for institutions of higher education and his monographs on theoretical physics are characterized by precision of exposition and richness of scientific material, combined with exceptional clarity and the presentation of profound physical ideas. His monographs on theoretical physics are widely known throughout the world. The first book of his course on theoretical physics, Statisticheskaya fizika (“Statistical Physics,” 1938), was followed by Mekhanika (“Mechanics”) and Teoria polya (“Field Theory”)

In his last years Landau, together with E. M. Lifshits, continued to work on a course of theoretical physics. In 1948 a new book of this course appeared, Kvantovaya mekhanika (“Quantum Mechanics”), as well as a revised edition of Teoria polya. In 1951 he published a completely new work on statistical physics and, in 1953, Mekhanika sploshnykh sred (“The Theory of Elasticity”). A course of lectures on general physics, given by Landau in the Moscow Institute of Physics and Technology was published in 1949, followed in 1955 by a course of lectures in the theory of the atomic nucleus written with Y. A. Smorodinsky. Another volume in this series, Elektrodinamika sploshnykh sred (“Electrodynamics of Continuous Media”), appeared in 1957. The authors’ continuing revisions of these works were tantamoung to the writing of a new book.

Landau created a very important scientific school. His students worked in the most varied field of theoretical physics and became distinguished scientists. Among his students were E. M. Lifshits, I. Y. Pomeranchuk, I. M. Lifshits, A. S. Kompaneyts, A. I. Akhiezer, V. B. Berestetsky, I. M. Shmushkevich, V. L. Ginzburg, A. B. Migdal, Y. A. Smorodinsky, I. M. Khalatnikov, A. A. Abricossov, and K. A. Ter-Martirosian.

Landau’s scientifc achievements received wide recognition. He was elected to membership in the Academy of Sciences of the U.S.S.R. and was awarded the title of Hero of Socialist Labor. Landau received the State Prize of the U.S.S.R. three times, and in 1962 he was awarded the Lenin Prize.

International recognition was expressed by the award of the Nobel Prize in physics in 1962; he was also elected member of many foreign academies and societies. In 1951 he was chosen a member of many foreign academies and societies. In 1951 he was chosen a member of the Danish and, in 1956, the Netherlands academies of science. In 1959 he was elected a member of the British Physical Society and in 1960 of the Royal Society. In the same year he became a member of the U. S. National Academy of Sciences and the American Academy of Arts and Sciences and was awarded the F. London Prize (U.S.A.) for research in low-temperature physics and the Max planck Medal (West Germany).

A tragic accident cut short Landau’s scientific work. In January 1962 he sustained severe injuries in an automobile accident and for several months lingered between life and death. Through remarkable efforts the life of this great physicist was prolonged for six years.

BIBLIOGRAPHY

I. Original Works. Landau’s writings include “Diamagnetismus der Metalle,” in Zeitschrift für Physik, 64 (1930), 629; “Extension of the Uncertainty Principle to Relativistic Quantum Theory,” ibid., 69 (1931), 56, written with R. Peierls; “Eine mögliche Erklàrung der Feldabhàngigkeit der Suszeptibilitàt bei niedrigen Temperaturen,” in Soviet Physics4 , no. 4,(1933), 675; “Struktur der unverschobenen Streulinie,” ibid., 5 , no. 1 (1934), 172, written with G. Platschek; “On the Theory of the Dispersion of Magnetic Permeability in Ferromagnetic Bodies,” ibid., 8 , no. 2 (1935), 153, written with E. Lifshits; “Zur Theorie der Schalldispersion,” ibid., 10 , no. 1 (1936), 34, written with E. Teller; “Die kinetische Gleichung fü den Fall coulombscher Wechselwirkung,” ibid., 10 , no. 2 (1936), 154; “Zur Theoric der Supraleitfàhigkeit,” ibid., 11 , no. 2 (1937), 129; and “K teorii fazovykh perekhodov “(“Toward a Theory of Phase Transitions”), in Zhurnal eksperimentalnoi teoreticheskoi fiziki, no. 7 (1937), 19.

Subsequent works are “The Cascade Theory of Electronic Showers,” in Proceedings of the Royal Society, 166A (1938), 213, written with G. Rumer; Statisticheskaya fizika (“Statistical Physics “Moscow—Leningrad, 1938), written with E. Lifshits; “Teoria sverkhtekuchesti gelia-2” (“Theory of the Superfluidity of Helium II”), in Zhurnal eksperimentalnoi i teoreticheskoi fiziki, no. 11 (1941), 592; Teoria polya (“Field Theory” Moscow-Leningrad, 1941; rev. ed. 1951), written with E. Lifshits, “K teorii promezhutochnogo sostoyania sverkhprovodnikov” (“Toward a Theory of the Intermediate State of Superconductors”), in Zhurnal eksperimentalnoi i teoreticheskoi fiziki, 13 (1943), 377; “On the Theory of the Intermediate State of Super-conductors,” in Fizicheskii zhurnal, 7 , no. 3 (1943), 99; Mekhanika sploshnykh sred (“The Theory of Elasticity” Moscow-Leningrad, 1944), written with E. Lifshits; and “On the Energy Loss of East particles by Ionization,” in Fizicheskii zhurnal, 8 , no. 4 (1944), 201.

Later writings are “on the Theory of Superfluidity of Helium II,” in Fizicheskii zhurnal, 11 , no. 1 (1947), 91; Kvantovaya mekhanika (“Quantum Mechanics” Moscow-Leninggrad, 1948), written with E. Lifshits; “Asimptoticheskoe vyrazenie dlya funktsii Grina elektrona v kvantovoy elektrodinamike” (“An Asymptotic Expression for Green’s Function of the Electron in Quantum Electrodynamics”), written with A. Abricossov and 1. Khalatnikov, in Doklady Akademii nauk SSSR, 95 (1954), 1177; “O tochechnom vzaimodeystvii v kvantovoy elektrodinamike” (“On Point Interaction in Quantum Electrodynamike”), ibid, 102 (1955), 489, written with I. Pomeranchuk; L ektsii po teorii atomnogo radra (“Lectures on the Theory of the Atomic Nucleus” Moscow, 1955), written with Y. Smorodinsky; “On the Quantum Theory of Fields,” in Nuovo cimento, supp. 3, no. 1 (1956), 80, written with A. Abricossov and I. Khalatnikov; “O zakonakh sokhranenia pri slabykh vzaimodeystviakh” (“On the Laws of Conservation in Weak Interactions”), in Zhurnal eksperimentalnoi i teorticheskoi fiziki, 32 , no. 2 (1957), 405; and “Ob analiticheskikg svoystvakh vershinnykh chastey v kvantovoy teorii polya” (“On the Analytical Properties of the Vertex Funtion in Quantum Field Theory”), ibid, 37 , no. 1 (1959), 62.

II. Secondary Literature. See V. B. Berestetsky, “Lev Davidovich Landau k 50-letiyu so dnya rozhdenia” (“Lev Davidovich Landau on the Fiftieth Anniversary of His Birth”), in Uspekhi fizicheskikh nauk, 64 , no. 3 (1958), 615.

A. T. Grigorian

Lev Davidovich Landau

views updated May 21 2018

Lev Davidovich Landau

The Soviet theoretical physicist Lev Davidovich Landau (1908-1968) developed a mathematical theory that explained the properties of superfluidity and superconductivity of helium at temperatures close to absolute zero.

Lev Landau, called "Dau" by his students and close associates, was born on Jan. 22, 1908, in Baku, the capital of Azerbaidzhan, to parents of middle-class Jewish background. At 14 he entered the University of Baku; then, in 1924, he transferred to Leningrad State University. In 1927 he graduated with a doctorate from the faculty of physics. Between 1927 and 1929 he continued his postgraduate studies at the Physicotechnical Institute of Leningrad.

In 1929 Landau left the Soviet Union to study for a year and a half at the Institute for Theoretical Physics in Copenhagen as well as at scientific centers in Germany, Switzerland, Great Britain, and the Netherlands. During his stay at the institute in Copenhagen, he became closely associated with the Danish physicist Niels Bohr. Bohr invited Landau in 1933 and 1934 to attend several conferences on theoretical physics. When abroad, Landau published at the age of 22 his classic theory on the diamagnetism of electrons in a metal (Landau's diamagnetism).

Soon after returning to Leningrad, in 1932 Landau received an assignment to head the theoretical section of the Ukrainian Physicotechnical Institute; he also joined the faculties of the Kharkov Institute of Machine Construction and the University of Kharkov. In Kharkov the Landau school of theoretical physics had its beginning.

Between 1938 and 1960 Landau, together with his student and collaborator E. M. Lifshits, wrote a series of volumes under the heading of Course of Theoretical Physics, covering mechanics, classical field theory, quantum mechanics, relativistic quantum theory, statistical physics, fluid mechanics, theory of elasticity, electrodynamics of continuous media, and physical kinetics. Some of the sections are actually based on original research performed by the authors. There are few works on contemporary physics that match the Course of Theoretical Physics in terms of clarity of exposition and scope of treatment; it is therefore not surprising that in April 1962 this veritable encyclopedia received the Lenin Prize.

Low-temperature Physics

In 1937 Landau arrived at the Institute of Physical Problems of the Soviet Academy of Sciences to head its theoretical section. He concentrated on certain paradoxical results obtained from experiments with helium near absolute zero. Helium II is virtually frictionless in its motion; yet when it is placed between two rotating disks, a force, indicating the presence of viscosity, can be measured. In another experiment a flask containing liquid helium was immersed in a bath of liquid helium and then heated; liquid helium was observed to flow out of the flask, but the flask remained full. To explain this paradoxical behavior of liquid helium, Landau regarded helium II as a "quantum liquid" whose properties could not be treated within the framework of classical mechanics. He presumed that helium II possessed two simultaneous forms of motion: normal, which is viscous and transports heat, and superfluid, possessing neither viscosity nor thermal conductivity.

The paradox associated with the non-emptying flask was resolved by Landau's theory, which predicted a superfluid countercurrent whose behavior conforms to the hydrodynamic laws governing ideal and nonviscous fluids with irrotational flow. Landau's theory also predicted that two velocities of sound waves occur if sound is transmitted through helium II. The first sound wave oscillates in helium II as does an ordinary sound wave in an ordinary fluid. But the second sound wave is unique to superfluids. Landau called this wave a "zero" sound wave. For his work in low-temperature physics Landau received the Stalin Prize in 1941, the Fritz London Award in 1960, and the Nobel Prize in 1962.

Other Scientific Contributions

Landau was appointed a full professor of physics at Moscow State University in 1943. In 1946 he was elected to full membership of the Soviet Academy of Sciences, won the Stalin Prize for his thermodynamic theory of phase transitions in solid bodies and of symmetry properties, and published a classic paper on the vibrations of the electronic plasma. Landau's work on the oscillations in plasma is recognized as a pioneering study on the road to harnessing thermonuclear power. It is believed that in the postwar period he made significant contributions to the development of Soviet atomic capability and the success of Soviet rocketry.

In his lifetime Landau published over 120 works covering the areas of hydrodynamics, aerodynamics, thermodynamics, astrophysics, quantum field theory, solid-state matter, cryogenics, nuclear physics, and cosmic rays. He received international acclaim for his achievements in theoretical physics. He was elected to membership in the English and the French Physical Society, the Dutch and the Danish Royal Academy of Sciences, the National Academy of Sciences of the United States, the American Academy of Arts and Sciences, the New York Academy of Sciences, and the London Royal Society. In addition to the previously mentioned prizes, Landau received in 1960 the Max Planck Medal from West Germany.

Personality and Outlook

Those who worked closely with Landau appreciated his enthusiasm for science, devotion to creativity in physics, and dedication to high scientific principles. Some have characterized Landau as a "salon" Communist who accepted the ideals of communism, but there is no evidence indicating that he ever joined the Communist party.

Landau revealed in Komsomolskaia pravda, dated July 8, 1964, to a stunned Soviet readership that he too had been caught up in the Stalinist mass purges and that he had been arrested in 1938 as a German spy—despite his Jewish background. After a year's detention Landau had emerged, emaciated and sickly, his black hair turned gray. Ironically, in subsequent years Soviet newspapers portrayed him as an "enthusiastic public-spirited citizen" whose scientific services were highly appreciated by the Soviet government. If there was any crime that Landau was guilty of, it was nonconformism. He appeared at state functions in a checkered sport shirt and at the Moscow Art Theater in sandals. He did not hesitate to lend support to modernistic trends in Soviet art. And he encouraged Soviet scientists to engage in discussions of the philosophical problems of science, thus preventing narrow party ideologues from dominating the scientific field.

On Jan. 7, 1962, Landau was seriously injured in an automobile accident. The process of recovery was slow. On Dec. 10, 1962, he was well enough to receive the Nobel Prize from the Swedish ambassador to Moscow. He died on April 1, 1968. With his passing, the Soviet Union lost its most outstanding theoretical physicist.

Further Reading

The only book-length biography of Landau in English is Alexander Dorozynski, The Man They Wouldn't Let Die (1965). Consult also the biographies in Nobel Foundation, Nobel Lectures: Physics, vol. 3: 1942-1962 (1967), and Royal Society, Biographical Memoirs of Fellows of the Royal Society, vol. 15 (1969). There is a biographical sketch of Landau by Albert Parry in George W. Simmonds, ed., Soviet Leaders (1967). Some of Landau's scientific contributions are discussed by Oscar Buneman in Morton Mitchner, ed., Radiation and Waves in Plasmas (1961); Thomas Howard Stix, The Theory of Plasma Waves (1962); I. M. Khalatnikov, An Introduction to the Theory of Superfluidity (trans. 1965); and J. F. Allen, ed., Superfluid Helium (1966). □

Landau, Lev Davidovich

views updated May 29 2018

LANDAU, LEV DAVIDOVICH

LANDAU, LEV DAVIDOVICH (1908–1968), Russian physicist and Nobel Prize winner. Born in Baku, Landau was a young prodigy in mathematics and was allowed to register at Baku University in the faculties of chemistry, physics, and mathematics at the age of 14, and graduated from Leningrad University when he was 19. In 1932 he was appointed head of the theoretical department of the Kharkov Physical-Technical Institute and in 1934 was granted his doctorate without presenting a thesis. He became a professor a year later. While working in Copenhagen with Niels *Bohr, he developed a theory of the diamagnetism of metals known as "Landau's diamagnetism." He also published two comprehensive, seminal works on ferro-magnetic substances in 1936 and 1937. He did research in many fields of physics: low temperature; turbulence; acoustics; plasma theory; energy of stars; quantum field theory; and the neutrino. His outstanding contribution was in the field of low temperatures carried out under the auspices of the Institute for Physical Problems in Moscow, which he joined in 1937. In 1962 Landau was awarded the Nobel Prize for physics for his "pioneering theories for condensed matter, especially liquid helium." Although Landau had been awarded the Stalin Prize three times for his work in theoretical physics, he was imprisoned during Stalin's purge, from 1937 to 1939, allegedly as a German spy. He was released when Professor Peter Kapitza, head of his Institute, declared that he would stop all his own scientific work unless Landau was freed. Landau suffered severe injuries in a car crash in 1962, but intensive medical treatment enabled him to live another six years although without resuming his researches. Among his numerous published works are O svoystvakh metallov pri ochen nizkikh temperaturakh ("Properties of Metals at Very Low Temperatures," 1936); Ob istochnikakh zvezdnoy energii ("Sources of Stellar Energy," 1937); O kolebaniyakh elektronnoy plazmy ("Fluctuations of Electronic Plasma," 1946); and O kvantovoy teorii polya ("Quantum Field Theory," 1956).

bibliography:

A. Dorozynski, The Man They Wouldn't Let Die (1965); V.B. Berestetski, in: Uspekhi fizicheskikh nauk, 64 no. 3 (1958); Prominent Personalities in the U.S.S.R. (1968), s.v.

[Maurice Goldsmith]

Landau, Lev Davidovich

views updated Jun 27 2018

Landau, Lev Davidovich (1908–68) Soviet physicist. In 1927, he proposed a concept for energy called the density matrix, later used extensively in quantum mechanics. He originated the theory that underlies the superfluid behaviour of liquid helium. In 1962, he received the Nobel Prize in physics for his research into condensed matter, especially helium.