Leonid Maksimovich Brekhovskikh (6 May 1917 – 15 January 2005; russian: Леони́д Макси́мович Бреховски́х) was a

Soviet The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, ...

and

Russian Russian(s) refers to anything related to Russia, including: *Russians (, ''russkiye''), an ethnic group of the East Slavic peoples, primarily living in Russia and neighboring countries *Rossiyane (), Russian language term for all citizens and peo ...

scientist known for his work in

acoustical Acoustics is a branch of physics that deals with the study of mechanical waves in gases, liquids, and solids including topics such as vibration, sound, ultrasound and infrasound. A scientist who works in the field of acoustics is an acoustician ...

and

physical oceanography Physical oceanography is the study of physical conditions and physical processes within the ocean, especially the motions and physical properties of ocean waters. Physical oceanography is one of several sub-domains into which oceanography is divi ...

Early life and education

Brekhovskikh was born to a

peasant A peasant is a pre-industrial agricultural laborer or a farmer with limited land-ownership, especially one living in the Middle Ages under feudalism and paying rent, tax, fees, or services to a landlord. In Europe, three classes of peasants ...

family in Strunkino, a small village in

Vologda Governorate Vologda Governorate (russian: link=no, Вологодская губерния, ''Vologodskaya guberniya'', ''Government of Vologda'') was an administrative division (a '' guberniya'') of the Russian Empire and the Russian SFSR, which existed fr ...

(now

Arkhangelsk Oblast Arkhangelsk Oblast (russian: Арха́нгельская о́бласть, ''Arkhangelskaya oblast'') is a federal subjects of Russia, federal subject of Russia (an oblast). It includes the Arctic Ocean, Arctic archipelagos of Franz Josef Land ...

Russia Russia (, , ), or the Russian Federation, is a List of transcontinental countries, transcontinental country spanning Eastern Europe and North Asia, Northern Asia. It is the List of countries and dependencies by area, largest country in the ...

. He graduated from

Perm State University Perm State University (now Perm State National Research University; russian: Пермский университет, Пермский государственный университет, , romanised: , ) or PSU, PSNRU (russian: ПГУ, , ...

in 1939, from which he received his university degree, and studied under

Igor Tamm Igor Yevgenyevich Tamm ( rus, И́горь Евге́ньевич Тамм , p=ˈiɡərʲ jɪvˈɡʲenʲjɪvitɕ ˈtam , a=Ru-Igor Yevgenyevich Tamm.ogg; 8 July 1895 – 12 April 1971) was a Soviet physicist who received the 1958 Nobel Prize in ...

at the

Lebedev Physical Institute The Lebedev Physical Institute of the Russian Academy of Sciences (LPI RAS or just LPI) (in russian: Физи́ческий институ́т имени П.Н.Ле́бедева Российской академии наук (ФИАН)), situated ...

(FIAN). There, he received his

Candidate of Sciences Candidate of Sciences (russian: кандидат наук, translit=kandidat nauk) is the first of two doctoral level scientific degrees in Russia and the Commonwealth of Independent States. It is formally classified as UNESCO's ISCED level 8, "do ...

degree (PhD) in Physics in 1941 for his thesis on

X-ray crystallography X-ray crystallography is the experimental science determining the atomic and molecular structure of a crystal, in which the crystalline structure causes a beam of incident X-rays to diffract into many specific directions. By measuring the angles ...

. After his PhD, he joined FIAN's acoustical laboratories and worked on a naval defence project to develop protection against acoustically triggered mines. He later developed a theory of the propagation of acoustical waves in layered media, for which he received his DSc in Physics and Mathematics from FIAN in 1947.

Research work

During 1946, his research in the

Sea of Japan The Sea of Japan is the marginal sea between the Japanese archipelago, Sakhalin, the Korean Peninsula, and the mainland of the Russian Far East. The Japanese archipelago separates the sea from the Pacific Ocean. Like the Mediterranean Sea, it h ...

led him to the discovery of the

deep sound channel The SOFAR channel (short for sound fixing and ranging channel), or deep sound channel (DSC), is a horizontal layer of water in the ocean at which depth the speed of sound is at its minimum. The SOFAR channel acts as a waveguide for sound, and low ...

, a concept which would eventually lead to the foundation of modern

acoustical oceanography Hydroacoustics is the study and application of sound in water. Hydroacoustics, using sonar technology, is most commonly used for monitoring of underwater physical and biological characteristics. Hydroacoustics can be used to detect the depth ...

. This was discovered independently by

Maurice Ewing William Maurice "Doc" Ewing (May 12, 1906 – May 4, 1974) was an American geophysicist and oceanographer. Ewing has been described as a pioneering geophysicist who worked on the research of seismic reflection and refraction in ocean basi ...

and

J. Lamar Worzel J. Lamar Worzel (February 21, 1919 – December 26, 2008) was an American geophysicist known for his important contributions to underwater acoustics, underwater photography, and gravity measurements at sea. Life Worzel was born on February ...

in the US almost at the same time. In 1953, Brekhovskikh left FIAN and founded the Andreyev Acoustics Institute in Moscow, which he directed until 1961 (he remained a department head there until his leaving, in 1980). At the Acoustics Institute, he participated in the construction and design of two acoustical research ships, the ''Sergey Vavilov'' and the ''

Pyotr Lebedev Pyotr Nikolaevich Lebedev (; 24 February 1866 – 1 March 1912) was a Russian physicist. His name was also transliterated as Peter Lebedew and Peter Lebedev. Lebedev was a creator of first scientific school in Russia. Career Lebedev made his do ...

'', which participated in the POLYGON experiment along with four other ships. These ships observed the mesocale

eddies In fluid dynamics, an eddy is the swirling of a fluid and the reverse current created when the fluid is in a turbulent flow regime. The moving fluid creates a space devoid of downstream-flowing fluid on the downstream side of the object. Fluid beh ...

for the first time, confirming the predictions made by

Henry Stommel Henry Melson Stommel (September 27, 1920 – January 17, 1992) was a major contributor to the field of physical oceanography. Beginning in the 1940s, he advanced theories about global ocean circulation patterns and the behavior of the Gulf Stream ...

in the mid 1960s. From 1953 to 1966, he was a professor of physics and a head of department at the

Moscow State University M. V. Lomonosov Moscow State University (MSU; russian: Московский государственный университет имени М. В. Ломоносова) is a public research university in Moscow, Russia and the most prestigious ...

. From 1969 until the

dissolution of the Soviet Union The dissolution of the Soviet Union, also negatively connoted as rus, Разва́л Сове́тского Сою́за, r=Razvál Sovétskogo Soyúza, ''Ruining of the Soviet Union''. was the process of internal disintegration within the Sov ...

in 1992, he was a member of the presidium of the

Academy of Sciences of the Soviet Union The Academy of Sciences of the Soviet Union was the highest scientific institution of the Soviet Union from 1925 to 1991, uniting the country's leading scientists, subordinated directly to the Council of Ministers of the Soviet Union (until 1946 ...

. He also taught physics and was a head of department at the

Moscow Institute of Physics and Technology Moscow Institute of Physics and Technology (MIPT; russian: Московский Физико-Технический институт, also known as PhysTech), is a public research university located in Moscow Oblast, Russia. It prepares speciali ...

from 1975 to 1997. In 1980, Brekhovskikh left the Acoustic Institute for the

Shirshov Institute of Oceanology The Shirshov Institute of Oceanology ( P.P. Shirshov Institute of Oceanology (IO) RAN, russian: Федеральное государственное бюджетное учреждение науки Институт океанологии имен ...

, where he led the acoustics department until his death.

Publications

During his life, he wrote several books on acoustical oceanography, his most famous being ''Waves in Layered Media'', first published in 1956. Brekhovskikh died on 15 January 2005, in

Moscow Moscow ( , US chiefly ; rus, links=no, Москва, r=Moskva, p=mɐskˈva, a=Москва.ogg) is the capital and largest city of Russia. The city stands on the Moskva River in Central Russia, with a population estimated at 13.0 million ...

, from

heart failure Heart failure (HF), also known as congestive heart failure (CHF), is a syndrome, a group of signs and symptoms caused by an impairment of the heart's blood pumping function. Symptoms typically include shortness of breath, excessive fatigue, a ...

Books

* * * *

Awards and memberships

* Walter Munk Award (1996) * Lenin Prize (1970) * Rayleigh Gold Medal (UK Institute of Acoustics, 1977) *

National Academy of Sciences The National Academy of Sciences (NAS) is a United States nonprofit, non-governmental organization. NAS is part of the National Academies of Sciences, Engineering, and Medicine, along with the National Academy of Engineering (NAE) and the Nati ...

References

External links

A short biography of Brekhovskikh

{{DEFAULTSORT:Brekhovskikh, Leonid 1917 births 2005 deaths 20th-century Russian physicists People from Solvychegodsky Uyezd People from Vilegodsky District Foreign associates of the National Academy of Sciences Full Members of the Russian Academy of Sciences Full Members of the USSR Academy of Sciences Academic staff of the Moscow Institute of Physics and Technology Academic staff of Moscow State University Perm State University alumni Heroes of Socialist Labour Stalin Prize winners Lenin Prize winners Recipients of the Order "For Merit to the Fatherland", 3rd class Recipients of the Order of Lenin Recipients of the Order of the Red Banner of Labour Recipients of the USSR State Prize Russian oceanographers Russian physicists Soviet oceanographers Soviet physicists Burials in Troyekurovskoye Cemetery