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BIOGRAPHIES OF GREAT SCIENTISTS
Stoletov Alexander Grigorievich
Directory / Biographies of great scientists
Alexander Grigoryevich Stoletov was born on July 29 (August 10), 1839, in the family of a poor Vladimir merchant. His father, Grigory Mikhailovich, owned a small grocery store and a leather dressing workshop. The house had a good library, and Sasha, having learned to read at the age of four, began to use it early. At the age of five, he already read quite freely. Alexander grew up as a fragile, sickly boy, and reading became his favorite pastime. As a child, he became acquainted with the works of Pushkin, Lermontov, Gogol, Zhukovsky and other Russian writers. Under their influence, he begins to write poems dedicated to various family celebrations. Later, in the gymnasium, together with his comrades, he publishes a handwritten journal, where he publishes the autobiographical story "My Memories". In addition to Sasha, there were five more children in the family. Under the influence of his older brother Nikolai, Sasha begins to learn French and soon, imperceptibly, reads and speaks quite decently. Together with his older sister Varenka, he is engaged in music and is so fond of it that he begins to think about whether he should become a professional musician. Music became a good companion of Stoletov for life. Often he rested at the piano after a difficult lecture or hard work in the laboratory. In 1849, Alexander entered the Vladimir Gymnasium, from which he graduated in 1856. In the last years of study at the gymnasium, Alexander's inclinations were clearly defined. His favorite subjects are mathematics and especially physics. In the autumn of the same year, 1856, Stoletov was enrolled in the Faculty of Physics and Mathematics of Moscow University as a "state-owned" student, that is, receiving a state scholarship. Stoletov lives in poverty, has little money, but, despite this, he is very reluctant to agree to private lessons and translations, rightly believing that these additional classes distract him from science. All time belongs and is given only to her! The outstanding scientific abilities of Alexander, his great love for knowledge were noticed and appreciated by the teachers. In 1860, Stoletov graduated with honors from the university, and immediately the leadership of the faculty began to fuss about leaving the young candidate at the university. But the request is denied. Only on September 5, 1861, the long-awaited permission finally arrives. During the elapsed time, Stoletov managed to prepare for the master's exam, and on October 16 he submits a petition to the rector. The exam was passed successfully, but the defense of the dissertation is unexpectedly postponed. Professors K. A. and S. A. Rachinsky donated a scholarship to the university for sending a worthy candidate on a business trip abroad for two years. The choice fell on Stoletov, and in the summer of 1862 he left Moscow. Alexander spent three years abroad. He studied in Heidelberg, Göttingen and Berlin with Kirchhoff, Helmholtz, Weber, Magnus and other famous scientists. Studied as always selflessly. Kirchhoff called Stoletov his most talented student. Abroad, Alexander Grigorievich completed his first scientific work. Together with K. A. Rachinsky, he tried to establish whether the dielectric properties of the medium in which magnets or electric current conductors are immersed affect the interaction between them. The result is negative. The researchers found that the dielectric properties of the medium do not affect the magnitude of the electromagnetic interaction. In December 1866, Stoletov returned to his homeland, and the following year received a position as a teacher of mathematical physics and physical geography at Moscow University. The students like the new young teacher. Stoletov's lectures were full of many interesting facts that helped explain obscure, controversial points, and more fully reveal the topic of the message. Finally, Stoletov takes up his master's thesis. It is devoted to the "general problem of electrostatics", over the solution of which many scientists struggled. Its meaning is as follows. If another conductor is brought to an uncharged conductor, charged, for example, negatively, then charges will appear on the first conductor: on the side closest to the charged body - positive, on the opposite side - negative. These induced charges, in turn, act on the charged conductor, and the charges on it are redistributed. This redistribution of charges will in turn cause a change in the distribution of charges on the other conductor, and so on. This will continue until electrostatic equilibrium is established between the two conductors. This task is very difficult and only two scientists managed to cope with it - Morphy and J. Thomson. Stoletov wanted to solve it in the most general form: in the case of the interaction of any arbitrary number of conductors. And he solved this problem. In May 1869, Stoletov brilliantly defended his master's thesis and was approved as an assistant professor. Sleepless nights, excessive work and nervous tension affect the health of the young scientist. He falls ill and spends about a year in various hospitals. He is forbidden to read, write, engage in any kind of mental activity. It was the most painful period in the life of Stoletov. Finally, a council of professors allows him to start teaching students. And immediately all the recommendations of doctors to spare their health are forgotten, Alexander Grigorievich again completely devotes himself to pedagogical and scientific activities. At that time, Moscow University, like other higher educational institutions in Russia, did not have a physical laboratory. To conduct scientific research, Russian scientists were forced to go abroad. Stoletov set himself the goal of creating such a laboratory. The whole year of 1870 is spent in efforts to set up the first physical laboratory in Russia. Studies in science take away from Alexander Grigorievich all the time at his disposal. He remained single for the rest of his life. In 1871, Stoletov began work on his doctoral dissertation. Now he is interested in the magnetic properties of iron. Knowing them is very important for practice. Electrical engineering at that time was not yet a science. The creation of a good electric machine was preceded by countless experiments on the selection of optimal design dimensions. And one of the most important tasks of electrical engineering was to find out how iron is magnetized. Until the laboratory is ready, Stoletov goes abroad. He spends only four months in Kirchhoff's laboratory in Heidelberg, but he manages to do a lot. He thinks over and designs an apparatus for studying the magnetic properties of iron, and conducts all the planned experiments. The important results obtained by Stoletov gave the creators of electric motors and dynamos the key to solving many of the problems facing them. In 1872, Stoletov successfully defended his doctoral dissertation "Research on the function of magnetization of soft iron" and the following year he was approved as an ordinary professor at Moscow University. In the autumn of 1872, another significant event took place: finally, a physics laboratory was opened at the university, for the construction of which Stoletov spent so much effort and money. It was the first teaching and research physical laboratory in Russia. Now Russian scientists did not have to travel abroad to conduct the necessary experiments! Starts his first experimental work at home and Stoletov. He sets up a long-conceived experiment to determine the relationship between electrostatic and electromagnetic units. The proportionality coefficient turns out to be close to the speed of light. This suggests not only that light is also an electromagnetic phenomenon, but also serves as an indirect confirmation of the validity of Maxwell's theory, which many scientists at that time did not recognize. Stoletov widely opens the doors of his laboratory to physicists working in other higher educational institutions in Russia. Alexander Grigoryevich does a lot of popularizing work in the Society of Natural Science Lovers, of which he is an indispensable member, gives public lectures at the Polytechnic Museum, publishes popular science articles in magazines for non-specialists. He wants to introduce science to as many people as possible. After his work on "The Function of the Magnetization of Iron", Stoletov's name became widely known abroad. In 1874, he was invited to the celebrations on the occasion of the opening of a physical laboratory at the University of Cambridge. In 1881, Stoletov adequately represented Russian science at the First World Congress of Electricians in Paris. He is the first Russian physicist to participate in an international congress. At the congress, Stoletov makes a report on his research on determining the proportionality factor between electrostatic and electromagnetic units, actively participates in the selection of electrical units of measurement. At the suggestion of our scientist, the unit of electrical resistance ohm and the standard of resistance were approved. In 1888, Alexander Grigorievich began research on the photoelectric effect, discovered a year earlier by Hertz. These studies brought Stoletov world fame. They lasted two years: from February 1888 to July 1890, and one can only wonder how much was done during this period by a person who was mainly engaged in teaching. Having repeated the experiments of Hertz, Wiedemann, Ebert and Galvax, Alexander Grigoryevich later developed a new technique that made it possible to construct a quantitative theory of the photoelectric effect. With the help of the setup he developed, Stoletov studied various aspects of the photoelectric effect. Based on the results of his experiments, he draws the following conclusions: a necessary condition for the photoelectric effect is the absorption of light by the cathode material; each element of the cathode surface participates in the phenomenon independently of the others; The phenomenon of the photoelectric effect is practically inertialess. By changing the voltage on the electrodes, Stoletov obtains the current-voltage characteristic of the photocell: the photocurrent increases with increasing voltage between the electrodes, and small currents are proportional to the voltage; Starting from a certain voltage value, the photocurrent practically does not change with increasing voltage, i.e., the photocurrent tends to saturation. Being confident that the magnitude of the photocurrent is definitely related to illumination, Stoletov conducts a series of experiments in order to establish this relationship. By changing the light intensity of the source, he found that the magnitude of the saturation photocurrent is proportional to the light flux incident on the cathode. In his experiments, the scientist came close to establishing the laws of electrical discharges in gases. The theory of such phenomena was built by the English physicist Townsend, using the results obtained by Stoletov. Townsend gave the law discovered by Stoletov about the dependence of the current strength of a non-self-sustaining discharge on pressure the name "Stoletov effect", under which he entered the world scientific literature. When in 1889 Stoletov came to Paris for the II International Congress of Electricians, scientists from all countries honored him as one of the most outstanding physicists of our time. At the beginning of 1893, three academicians, Chebyshev, Bredikhin and Beketov, nominated Stoletov as a member of the country's highest scientific institution. Despite the world fame of the scientist, the president of the academy, Grand Duke Konstantin, does not allow Stoletov's candidacy to run. The indignant brother of Alexander Grigoryevich, Nikolai, the general and hero of Shipka, asks the president of the academy why he personally crossed out the name of Stoletov from the lists of candidates. "Your brother has an impossible character," the Grand Duke replies with irritation. Despite the sympathy of his friends, Stoletov is hard pressed by the insult inflicted on him. And the university authorities are starting to show their disgrace to him more and more. All this greatly affects the health of Alexander Grigorievich. He is tormented by coughing, insomnia, everything is difficult for him and it is more difficult to leave the house. At the age of 55, as a result of continuous bullying, he becomes a sick old man. At the beginning of 1896, Stoletov suffered from severe erysipelas. As soon as he recovers from it, he falls ill again. Diseases torment the weakened organism, and on the night of May 14-15 (27) Alexander Grigoryevich dies of pneumonia. The significance of Stoletov as a scientist for Russian and world science is enormous. He created the first in Russia educational and research physical laboratory, founded the school of Russian physicists, made many discoveries. Based on the phenomenon of the photoelectric effect studied by Stoletov, photocells were created, which were widely used. Stoletov's vacuum installation for studying electrical phenomena in rarefied gases was the prototype of the electron tube, which made a real revolution in electrical engineering. Author: Samin D.K.
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