Mandelstam Leonid Isaakovich 04/22/1879, a native of Mogilev. He became a doctor of natural philosophy in 1902. The title of professor was awarded in 1913. Since 1929, academician of the Academy of Sciences of the USSR. For his labors he was awarded the Order of Lenin, the Order of the Red Banner of Labor. Prize winner - Lenin in 1931, State in 1942.
Young years of the future scientist
The biography of Leonid Isaakovich Mandelstam begins on April 22 (May 4 according to the old style) in 1879, when he was born. The deposit was the city of Mogilev. His family was highly educated. Father, Isaak Grigorievich, a social activist, worked for more than forty years in hospitals in Odessa. He was known as an obstetrician. Mother, Nina Lvovna Kogan, recognized pianist of the Odessa Conservatory.
The family moved to Odessa almost immediately after the birth of a son. Until 1897, Leonid Isaakovich studied at the gymnasium. She graduated with a silver medal. Then he entered the Novorossiysk University, which was located in Odessa. In this educational institution he studied at the Faculty of Physics and Mathematics. The choice was determined by the fact that since the last classes of the gymnasium Mandelstam was very passionate about the exact sciences, especially physics and mathematics.
The beginning of scientific activity
Leonid Mandelstam did not study at this university for long. In 1898, student unrest began and he was actively involved in these processes. This leads to the fact that he is arrested, and subsequently expelled from the University. However, he did not interrupt his pursuit of knowledge. In the same year he left Russia and entered the University of Strasbourg. There he continued to study physics and mathematics. Already during the training period, he established himself as an excellent speaker and popularizer of knowledge. Don gave presentations at a variety of physical and mathematical meetings. He participated in the experiments of a German physicist, later a Nobel laureate, Karl Brown.
In 1907, Mandelstam, who turned 28 years old, became a privat-docent. His studies on the problems of light scattering were recognized by experts so highly that they were put together with the works of brilliant scientists of that period. In 1913, he was already a professor at this University and a professor of physics.
Return to Russia
Mandelstam does not break ties with Russia and in 1914 he returned to the country. Becomes a private assistant professor in the city of Odessa. He begins to actively deal with the problems of radio engineering, provides scientific advice to a telegraph plant.
After the Odessa Polytechnic Institute was recreated in 1918, physicist Leonid Mandelstam was appointed professor. In 1922 he left for Moscow and began working at Moscow University. In 1925, he was already a professor at the University. Teaches students theoretical physics. After another three years, he was elected a corresponding member of the USSR Academy of Sciences, and in 1929 he became a full member of the Academy of Sciences.
Scientific work
The research and discoveries of Mandelstam are numerous; it encompassed various fields of science and technology. The list of areas of his interests includes optics, radiophysics, quantum mechanics, and the theory of nonlinear oscillations. One of the most recognized achievements of the scientist was the work in the field of studying electrical oscillations. The state discovered by him, so-called. weak communications have become a common concept.
In 1907, his analytical works on the problems of molecular scattering of light were combined in the publication: “On an Optically Homogeneous and Turbid Medium”. In it, he proved that light is scattered due to thermal fluctuations. Working at Moscow State University, Mandelstam opens up new effects in optics - combined light scattering. Together with the scientist M. Leontovich at the end of the twenties of the last century, he substantiated the theory of the penetration of particles through barriers. In it, he predicted the use of scattering matrices.
The discoveries and works of Leonid Isaakovich Mandelstam in radiophysics and in the study of the theory of oscillations gave impetus in the future to new directions in radio engineering, radio geodesy, aerodynamics, and acoustics. For their needs, he substantiated the theory of multivibrators and discovered a new type of resonant oscillations.
In 1930, Leonid Mandelstam was nominated for a Nobel Prize for his discovery in the field of light scattering.
Mandelstam - teacher and organizer
Leonid Isaakovich is also known as an outstanding organizer, lecturer, teacher. So, at the Polytechnic Institute in the city of Odessa, he managed to attract many famous Russian scientists to work. In the conditions of very difficult times, I found the opportunity to deliver general educational lectures and organize courses to study the properties of oscillations.
His teaching activities, as well as public lectures while working at Moscow State University, gathered very large audiences. Not only students came to listen to him, but also professors, engineers and mathematicians. Mandelstam’s hand-written lectures were distributed in handwritten form. And it was precisely such forms of his lectures that could have a great influence on various scientific studies, especially in the study of oscillations.
The main works and discoveries of Mandelstam:
- In 1911, he carried out unique work in the field of microscopic images, the results of which were recorded in scientific works.
- From 1914 to 1925, Leonid Isaakovich Mandelstam devoted himself to the problems of technical physics. He studied the possibility of transferring into the optics representations from the field of modulated oscillations.
- In 1918, he described in formulas the possibility of determining the degree of change in the length of the waves of scattered light.
- In 1926, he discovered selective scattering of light, predicted the behavior of light lines.
- In 1928, in collaboration with the scientist G. Landsberg, he made the discovery of the phenomenon of light scattering in crystals. He created the theory of Rayleigh scattering.
- While working at Moscow State University, he actually created a new field of radio engineering - radio geodesy. He invented and justified new methods of radiotelephone and radiotelegraph modulation. Developed innovative research methods for propagation of radio waves.
- In 1942, together with the scientist N. Papaleksi, laid the theoretical foundations for the use of radar in astronomy. Based on his ideas, in 1945 it became possible to carry out radar research of the moon.
A family
Leonid Isaakovich was married to Lydia Solomonovna Isaakovich. They got married in 1907. With her, he lived his whole life. She survived it for 18 years.
His son - Sergei Leonidovich - also became a famous physicist, died in 1990.
The biography of Leonid Mandelstam ends in 1994, November 27. On this day, he died due to heart disease. He was buried at the Novodevichy cemetery in Moscow. His name is immortalized in the name of one of the craters on the moon.
Scholarships for students at Moscow State University and at the Institute of Physics named after him were named after him. P. Lebedev.