Lev Semyonovich Pontryagin (1908-1988) - Soviet mathematician, one of the greatest mathematicians of the 20th century, academician of the USSR Academy of Sciences. Laureate of the Lenin Prize, the Stalin Prize of the 2nd degree and the USSR State Prize.
He made a significant contribution to algebraic and differential topology, oscillation theory, calculus of variations, control theory. The works of the Pontryagin school had a great influence on the development of control theory and the calculus of variations throughout the world.
There are many interesting facts in the biography of Pontryagin, which we will talk about in this article.
So, before you is a short biography of Lev Pontryagin.
Biography of Pontryagin
Lev Pontryagin was born on August 21 (September 3) 1908 in Moscow. He grew up and was brought up in a simple working class family.
The mathematician's father, Semyon Akimovich, graduated from 6 classes of the city school, after which he worked as an accountant. Mother, Tatyana Andreevna, worked as a dressmaker, while possessing good mental abilities.
Childhood and youth
When Pontryagin was 14 years old, he became the victim of an accident. As a result of the explosion of the primus, he received a serious burn to his face.
His health condition was in critical condition. As a result of the burn, he practically stopped seeing. The doctors' attempt to restore the teenager's sight turned out to be a failure.
Moreover, after the surgical intervention, Leo's eyes became very inflamed, as a result of which he could never see again.
For the father, the son's tragedy was a real blow, from which he could not recover. The head of the family quickly lost his ability to work and in 1927 he died of a stroke.
The widowed mother did her best to make her son happy. Without an appropriate mathematical education, she, together with Lev, began to study mathematics in order to prepare him for entering a university.
As a result, Pontryagin was able to successfully pass the exams at the university for the physics and mathematics department.
In the biography of Lev Pontryagin there was a very interesting incident that occurred at one of the lectures. When one of the professors was explaining another topic to the students, supplementing it with explanations on the blackboard, the voice of a blind Leo was suddenly heard: "Professor, you made a mistake on the drawing!"
As it turned out, the blind Pontryagin "heard" the arrangement of letters on the drawing and immediately guessed that there was a mistake.
Scientific career
When Pontryagin was only in his second year of university, he was already seriously engaged in scientific activities.
At the age of 22, the guy became an assistant professor of the Department of Algebra at his native university, and also ended up in the Research Institute of Mathematics and Mechanics of Moscow State University. 5 years later, he was awarded the degree of Doctor of Physical and Mathematical Sciences.
According to Lev Pontryagin, he was fond of mathematics in order to solve vital problems of society.
At this time, the biography of the scientist studied the works of Henri Poincaré, George Birkhoff and Marston Morse. Together with his associates, he often gathered at home to read and comment on the works of these authors.
In 1937, Pontryagin, together with his colleague Alexander Andronov, presented a work on dynamical systems that had applications. In the same year, a 4-page article "Rough Systems" was published in the Reports of the USSR Academy of Sciences, on the basis of which an extensive theory of dynamical systems was developed.
Lev Pontryagin made a significant contribution to the development of topology, which at that time was very popular in the scientific world.
The mathematician was able to generalize Alexander's duality law and, on its basis, develop the theory of characters of continuous groups (Pontryagin characters). In addition, he achieved high results in homotopy theory, and also determined the connections between Betti groups.
Pontryagin showed a keen interest in the theory of oscillations. He succeeded in making a number of discoveries in the asymptotics of relaxation oscillations.
A few years after the end of the Great Patriotic War (1941-1945), Lev Semyonovich became interested in the theory of automatic regulation. Later he succeeded in deriving the theory of differential games.
Pontryagin continued to "polish" his ideas together with his students. Ultimately, thanks to the collective work, mathematicians managed to formulate the theory of optimal control, which Lev Semenovich called the main achievement of all their activities.
Thanks to the calculations, the scientist was able to derive the so-called maximum principle, which later began to be called - the Pontryagin maximum principle.
For their achievements, a group of young scientists led by Lev Pontryagin was awarded the Lenin Prize (1962).
Pedagogical and social activities
Pontryagin paid great attention to the system of teaching mathematics in educational institutions.
In his opinion, schoolchildren should learn only the most important and effective methods of calculation that could be useful to them in later life. Pupils should not have acquired too deep knowledge, since they would not be useful to them in everyday life.
Also Lev Pontryagin advocated to present the material in understandable terms. He said that no builder would talk about 2 “congruent slabs” (or a seamstress about “congruent pieces of fabric”), but only as identical slabs (pieces of fabric).
During the 40-50s, Pontryagin repeatedly sought to acquit the repressed scientists. Thanks to his efforts, mathematicians Rokhlin and Efremovich were released.
Pontryagin was repeatedly accused of anti-Semitism. However, the mathematician stated that all such statements addressed to him were nothing more than slander.
Already in old age, Lev Pontryagin criticized projects related to the turning of Siberian rivers. He also achieved a discussion of mathematical errors regarding the level of the Caspian Sea at a meeting of mathematicians of the USSR Academy of Sciences.
Personal life
For a long time, Leo could not achieve success on the personal front. The mother was jealous of her son for his chosen ones, as a result of which she spoke about them only in a negative way.
For this reason, Pontryagin not only married late, but also endured serious trials in both marriages.
The first wife of the mathematician was the biologist Taisiya Samuilovna Ivanova. The couple legalized their relationship in 1941, having lived together for 11 years.
An interesting fact is that having never written a dissertation before, Lev Semyonovich wrote a Ph.D. thesis for his wife on the morphology of locust, very worried about her defense. When Taisiya successfully defended herself, Pontryagin decided that now he could part with her "with a clear conscience".
In 1958, the man remarried with Alexandra Ignatievna. He loved his wife very much and always tried to give her as much attention as possible.
Although Pontryagin was blind, he never needed anyone's help. He walked the streets himself, often falling and getting injured. As a result, there were many scars and abrasions on his face.
Moreover, in the middle of the last century, Lev Semenovich learned to ski and skate, and also swam in a kayak.
Last years and death
Pontryagin never had a complex because he was blind. He did not complain about his life, as a result of which his friends did not perceive him as blind.
A few years before his death, the scientist had had tuberculosis and pneumonia. On the advice of his wife, he became a vegetarian. The man stated that only a vegetarian diet helped him cope with illness.
Lev Semenovich Pontryagin died on May 3, 1988 at the age of 79.
Pontryagin Photos