Anatoly Aleksandrovich Vlasov (; – 22 December 1975) was a

Russian Russian(s) may refer to: *Russians (), an ethnic group of the East Slavic peoples, primarily living in Russia and neighboring countries *A citizen of Russia *Russian language, the most widely spoken of the Slavic languages *''The Russians'', a b ...

, later

Soviet The Union of Soviet Socialist Republics. (USSR), commonly known as the Soviet Union, was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 until Dissolution of the Soviet ...

, theoretical physicist prominent in the fields of

statistical mechanics In physics, statistical mechanics is a mathematical framework that applies statistical methods and probability theory to large assemblies of microscopic entities. Sometimes called statistical physics or statistical thermodynamics, its applicati ...

, kinetics, and especially in

plasma physics Plasma () is a state of matter characterized by the presence of a significant portion of charged particles in any combination of ions or electrons. It is the most abundant form of ordinary matter in the universe, mostly in stars (including th ...

Biography

Anatoly Vlasov was born in Balashov, in the family of a steamfitter. In 1927 he entered into the

Moscow State University Moscow State University (MSU), officially M. V. Lomonosov Moscow State University,. is a public university, public research university in Moscow, Russia. The university includes 15 research institutes, 43 faculties, more than 300 departments, a ...

(MSU) and graduated from the MSU in 1931. After the graduation Vlasov continued to work in the MSU, where he spent all his life, collaborating with Nobelists

Pyotr Kapitsa Pyotr Leonidovich Kapitsa or Peter Kapitza (, ; – 8 April 1984) was a leading Soviet physicist and Nobel laureate, whose research focused on low-temperature physics. Biography Kapitsa was born in Kronstadt, Russian Empire, to the Bessar ...

Lev Landau Lev Davidovich Landau (; 22 January 1908 – 1 April 1968) was a Soviet physicist who made fundamental contributions to many areas of theoretical physics. He was considered as one of the last scientists who were universally well-versed and ma ...

, and other leading physicists. He became a full Professor at the Moscow State University in 1944 and was the head of the theoretical physics department in the Faculty of Physics at Moscow State University from 1945 to 1953. He was a member of Communist Party of USSR since 1944 In 1970 he received the

Lenin Prize The Lenin Prize (, ) was one of the most prestigious awards of the Soviet Union for accomplishments relating to science, literature, arts, architecture, and technology. It was originally created on June 23, 1925, and awarded until 1934. During ...

Research

His main works are in

optics Optics is the branch of physics that studies the behaviour and properties of light, including its interactions with matter and the construction of optical instruments, instruments that use or Photodetector, detect it. Optics usually describes t ...

, physics of

crystal A crystal or crystalline solid is a solid material whose constituents (such as atoms, molecules, or ions) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions. In addition, macros ...

s, theory of

gravitation In physics, gravity (), also known as gravitation or a gravitational interaction, is a fundamental interaction, a mutual attraction between all massive particles. On Earth, gravity takes a slightly different meaning: the observed force b ...

, and

statistical physics In physics, statistical mechanics is a mathematical framework that applies statistical methods and probability theory to large assemblies of microscopic entities. Sometimes called statistical physics or statistical thermodynamics, its applicati ...

Optics

In optics he analyzed, partially with Vasily Fursov, spectral line broadening in gases at large densities (1936—1938). A new suggestion in these works was to use long range collective interactions between atoms for a correct description of spectra line broadening at large densities.

Plasma physics

Vlasov became world-famous for his work on plasma physics (1938) (see also). He showed that the

Boltzmann equation The Boltzmann equation or Boltzmann transport equation (BTE) describes the statistical behaviour of a thermodynamic system not in a state of equilibrium; it was devised by Ludwig Boltzmann in 1872.Encyclopaedia of Physics (2nd Edition), R. G ...

is not suitable for a description of plasma dynamics due to the existence of long range collective forces in the plasma. Instead, an equation known now as the Vlasov equation was suggested for the correct description to take into account the long range collective forces through a self-consistent field. The field is determined by taking moments of the distribution function described in Vlasov's equation to compute both the charge density and current density. Coupled with Maxwell's equations, the resulting system of differential equations are well-posed provided correct initial conditions and boundary conditions are provided. The Vlasov equation, which is related to the Liouville's equation and the collisionless Boltzmann equation, is fundamental to plasma physics. In 1945, Vlasov showed that this equation, with the collective interaction taken into account, can explain without any additional hypotheses and specifications such effects as the presence and spontaneous origin of eigenfrequencies in polyatomic systems, the spontaneous origin of crystal structure from a "gas" medium, and the presence and spontaneous origin of currents in the media due to the collective interaction of the particles.

Physics of crystals

In this subject Vlasov in particular studied using the linearized Vlasov equation the conditions for spontaneous origin of crystal structure in the medium and found the criteria for the origin of the periodic structure in terms of the temperature,

density Density (volumetric mass density or specific mass) is the ratio of a substance's mass to its volume. The symbol most often used for density is ''ρ'' (the lower case Greek letter rho), although the Latin letter ''D'' (or ''d'') can also be u ...

, and microscopic interaction of particles of the medium.

Selected publications

*A. A. Vlasov (1961). ''Many-Particle Theory and Its Application to Plasma''. New York, Gordon and Breach. ; . *A. A. Vlasov (1966). ''Statistical Distribution Functions'' n Russian Nauka. *A. A. Vlasov (1978). ''Nonlocal Statistical Mechanics'' n Russian Nauka, Moscow.

References

External links

Anatolii Aleksandrovich Vlasov (obituary)
(in English), I. P. Bazarov ''et al.'', ''Soviet Physics Uspekhi'' 19, 545—546 (1976).

in the

Great Soviet Encyclopedia The ''Great Soviet Encyclopedia'' (GSE; , ''BSE'') is one of the largest Russian-language encyclopedias, published in the Soviet Union from 1926 to 1990. After 2002, the encyclopedia's data was partially included into the later ''Great Russian Enc ...

Anatoly Vlasov
in the All-Russia Genealogical Tree {{DEFAULTSORT:Vlasov 1908 births 1975 deaths 20th-century Russian physicists People from Balashov Moscow State University alumni Academic staff of Moscow State University Recipients of the Lenin Prize Recipients of the Order of the Red Banner of Labour Plasma physicists Russian theoretical physicists Soviet physicists Burials at Donskoye Cemetery Russian scientists