The development of mathematics in our country, and throughout the world, is inextricably linked with the name of Sergei L. Sobolev. He made a fundamental contribution to this science and laid the foundation for the development of new directions. Sergei Lvovich is rightfully considered one of the greatest mathematicians of the 20th century. We will tell about his life and scientific activity in the article.
Biography
Sergei L. Sobolev was born in St. Petersburg 09/23/1908. His father, Lev Aleksandrovich, worked as a lawyer and took part in the revolutionary movement. Mother, Natalya Georgievna, in her youth was also a revolutionary and a member of the RSDLP. Later, she received a medical education and worked at the Leningrad Medical Institute as an assistant professor. Sergey Lvovich lost his father early, his mother raised him. She instilled in her son such qualities as integrity, honesty and determination.
From childhood, the future mathematician was distinguished by curiosity. He read a lot, was fond of different sciences, wrote poetry and played the piano. In 1924 he graduated from high school and wanted to go to medical school, but at that time he was accepted to the university only from the age of seventeen, and he was sixteen. Therefore, the young man went to study at the State Art Studio, the piano class. A year later, he entered the Faculty of Physics and Mathematics at Leningrad State University and at the same time continued to study in the studio. While studying at the university, he attended lectures by professors such as Vladimir Ivanovich Smirnov, Nikolai Maximovich Gunter, Grigory Mikhailovich Fichtenholtz. They had a great influence on the formation of Sobolev as a scientist.
The university program did not satisfy the curious student anymore, and he studied special literature. Undergraduate practice was held in the settlement bureau of the Leningrad plant "Electrosila". There Sergey Lvovich solved his first important task - he explained why shafts having insufficient cross-sectional symmetry have a new frequency of natural vibrations.
The beginning of scientific activity
In 1929, Sobolev graduated from high school and got a job at the Seismological Institute of the USSR Academy of Sciences, headed by Vladimir Ivanovich Smirnov. He worked in the theoretical department, where he was able to conduct several in-depth scientific studies. Together with Smirnov, he developed a methodology of functionally invariant solutions and then applied it to solving dynamic problems in the theory of elasticity. This technique formed the basis for the theory of propagation of elastic waves. In addition, Sergey Lvovich solved the famous Lamb problem and built a rigorous theory of Rayleigh surface waves.
In 1932, Sobolev began working at the Steklov Mathematical Institute (Steklov Mathematical Institute), in the department of differential equations. A year later, he was elected a corresponding member of the USSR Academy of Sciences for outstanding services in the field of mathematics.
Moscow period
In 1934, Sergei Sobolev moved to Moscow with the Mathematical Institute and was appointed head of the department. During this period, the scientist was engaged in functional analysis and research of the theory of partial differential equations. The methods and ideas proposed in these works subsequently became part of the golden fund of world science and were further developed in the works of many domestic and foreign mathematicians.
In the same year, at the All-Union Congress in Leningrad, Sobolev presented a series of reports on the theory of partial differential equations, in which he first laid out in detail the basics of the concept of “generalized functions”. In subsequent years, the mathematician developed in this direction. On the basis of the generalized derivative, he studied and introduced new functional spaces, which in the literature were called “Sobolev spaces”. The methods and ideas of the scientist were developed in computational mathematics, equations of mathematical physics and differential equations.
In 1939, at the age of thirty, Sergey Lvovich became a full member of the USSR Academy of Sciences. For many years he remained the youngest Soviet academician.
War and post-war years
At the beginning of the Second World War, Sobolev was appointed director of the Steklov Institute of Mathematics. The university was evacuated to Kazan, and, despite difficult conditions, the scientist was able to organize applied research in it. In 1943, Steklov Mathematical Institute was returned to Moscow, and Sergei Lvovich went to work at the Kurchatov Institute, where he began research in the field of atomic energy and the atomic bomb. Soon, the mathematician received the posts of first deputy director and chairman of the Academic Council.
In the years 1945-1948. in an atmosphere of deep secrecy, Sobolev, together with other scientists, created the country's atomic shield. Applied mathematical problems were put before him, requiring great efforts: it was necessary to calculate, predict and optimize complex processes that had never been studied before. Due to the tremendous work and extraordinary mathematical intuition, Sergey Lvovich managed to cope with the work in the given time. According to the recollections of the scientist’s wife, at that time he often went on distant business trips and was not at home for months.
main book
Over the years of work at the Kurchatov Institute, Sobolev was able to prepare for publication the main scientific work of his whole life - a book entitled "Some applications of functional analysis in mathematical physics." In this work, Sergey Lvovich systematically outlined the theory of functional spaces, which played an exceptional role in shaping the views of modern mathematicians. The book became a desktop for representatives of various scientific fields, was translated into various languages. In our country it was reprinted three times, and in America twice.
The concepts of a generalized solution and a generalized derivative are widely used in mathematics and became the basis of a new direction of research, which became known as the "theory of Sobolev spaces."
Work at MSU
In 1952, the Soviet mathematician Alexei Andreevich Lyapunov offered Sergey Lvovich a job at the Faculty of Mechanics and Mathematics of Moscow State University as a professor in the department of computational mathematics, formed three years earlier. Sobolev agreed and soon became head of the department. He held this position from 1952 to 1958, and during this time, together with Lyapunov, he actively proved the important purpose of cybernetics.
In 1955, the academician initiated the creation of a computer center at the department. Professor Ivan Semenovich Berezin was appointed its director. In a short period of time, the center became one of the most powerful in the country: in the first years of its existence, its computing power exceeded ten percent of the computing power of all computers then available in the Soviet Union.
Siberian period
In 1956, Sergei L. Sobolev and several other academicians proposed the creation of research centers in the east of the country. A year later, it was decided to form the Siberian Branch of the USSR Academy of Sciences as part of a number of research institutes, including the Novosibirsk Institute of Mathematics. Sobolev was appointed director of this institute. In 1958, he left the Faculty of Mechanics and Mathematics of Moscow State University and went to Novosibirsk. To the question of what made him leave for Siberia, which was essentially a scientific virgin at that time, Sergey Lvovich answered: "The desire to start something new and live several lives."
At the Institute of Mathematics, the scientist tried to present all the most important modern scientific fields. Here, research was conducted on logistics, algebra, geometry, computational mathematics, theoretical cybernetics, functional analysis, and differential equations. In the shortest possible time, the research institute became a major scientific center, known throughout the world. Today, the Institute of Mathematics of the SB RAS is named after Sobolev and is the largest research institute in the field of mathematics in Russia by the number of employees.
In Novosibirsk, Sergey Lvovich began to study cubator formulas and created his theory, proposing a radically new approach to numerical quadrature using the methods of generalized functions.
Awards and titles
In 1984, the academician returned to the capital and continued to work at the Steklov Institute. He was an excellent teacher and brought up a galaxy of followers. The brilliant social and scientific work of mathematics not only determined his great authority in our country, but also received international recognition. Sobolev was an honorary member of the American Mathematical Society and many world universities, was a foreign member of the Academies of Sciences in France, Berlin, Rome.
The merits of the scientist are marked by many state awards. Sergei Lvovich Sobolev was awarded seven orders of Lenin, orders of the Red Banner and the October Revolution, the “Badge of Honor”. He had the title of Hero of Socialist Labor. He was the owner of the Stalin Prizes and State Prizes of the USSR. In 1977, the Academy of Sciences of Czechoslovakia awarded the academician the Gold Medal "For Merit to Humanity and Science." In 1988, he was awarded the Lomonosov Gold Medal for outstanding scientific achievements.
Personal life
Sobolev had a friendly and large family: his wife, Ariadna Dmitrievna, MD, and seven children, five of whom became candidates of science. According to the eldest daughter of the mathematician Svetlana, the father often read to children of Pushkin, Akhmatov, Mayakovsky, Blok, Pasternak. He never put pressure on his daughters and sons, he always helped his wife, led a modest working life. With the whole family, the Sobolevs went on camping trips in the Caucasus and Crimea, during which Sergey Lvovich told the children a lot about natural and scientific phenomena. Svetlana recalled that when she was in fifth grade, her father told her the theory of relativity, and the girl understood everything in his story.
Memory
Sergei L. Sobolev died in Moscow on 01/03/1989 at the age of eighty. It rests at the Novodevichy cemetery of the capital.
In honor of the academician, a memorial plaque was installed on the building of the Institute of Mathematics in Novosibirsk. One of the classrooms of Novosibirsk State University was also named after him.
Sobolev Prize and Scholarship were established for students of NSU and young scientists of the SB RAS. In memory of mathematics, international congresses are held in Novosibirsk and Moscow.
In 2008, an international conference was held in the capital of Siberia, dedicated to the centenary of the birth of Sergei Lvovich. About six hundred applications were submitted to participate in it, but in fact four hundred mathematicians from around the world attended the event.