Rozhdestvensky, Dmitry Sergeevich

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ROZHDESTVENSKY, DMITRY SERGEEVICH

(b. St. Petersburg, Russia, 7 April 1876; d. Leningrad, U.S.S.R., 25 June 1940)

physics.

Rozhdestvensky’s father was a teacher in a Gymnasium. His parents encouraged him in his studies, and from childhood he studied foreign languages. He graduated in 1894 from the Gymnasium, with a silver medal, and entered St. Petersburg University. Rozhdestvensky graduated from the mathematical section of the university in 1900 and remained at the university to prepare for a teaching career. From 1901 to 1903 he worked with the physicist Paul Drude at the Institute of Physics in Giessen. On his return to Russia he became laboratory assistant at St. Petersburg University. He chose as the subject of his research the study of the course of anomalous dispersion near lines of absorption in sodium vapors. The lack of major specialists in optics at the university obliged Rozhdestvensky to work virtually independently, and he devised an original experimental method of research, which later was widely used. This project served as the theme for his master’s dissertation, which he defended in 1912 and for which he was awarded the Mendeleev Medal of the Academy of Sciences. Extending his method to potassium, rubidium, and cesium vapors, Rozhdestvensky in 1915 defended his doctoral dissertation on simple relationships in the spectra of alkali metals. In 1916 he was elected professor and head of the Physics Institute of Petrograd University and began to work with a group of scientists and engineers on the preparation of optical glass, in which the Russian army was seriously lacking during World War I.

Soon after the October Revolution Rozhdestvensky presented a detailed project for the organization of a State Optical Institute, which was created in 1918 and of which he was director until 1932. At the Institute, Rozhdestvensky created a leading school, from which came important Soviet scientists including A. N. Terenin, V. A. Fok, Y. F. Gross, S. E. Frish, and V. K. Prokofiev. In 1925 he was elected corresponding member of the Academy of Sciences of the U.S.S.R. and, in 1929, academician. In the Academy Rozhdestvensky headed the Spectroscopic Commission until the end of his life.

Rozhdestvensky’s research centered basically on three problems: anomalous dispersion near the lines of absorption in atomic spectra, the theory of atomic spectra, and the theory of the microscope. His quantitative research on anomalous dispersion was based on the experimental method that he developed of combining two spectral instruments, a diffraction grating and an interferometer, to obtain alternating light and dark bands. The visual demonstration of so-called hooks was an original way of showing refraction near the lines of absorption. This research made it possible for the first time to measure the numerical values of the ratios of intensity in the double lines of the alkali metals and the absolute values of the probability of quantum transitions, which play a very important role in the theory. The method was also successfully used for the study of discharge in gases.

Rozhdestvensky’s work in the theory of atomic spectra (1920–1924) was important for interpreting spectra in the period before quantum mechanics. This research was especially useful in the development of quantum mechanical methods of calculating spectral terms worked out by V. A. Fok. In the theory of the microscope (1939–1940) Rozhdestvensky considered practical conditions of illumination of an object, especially the most effective use of the microscope for transparent biological objects.

Rozhdestvensky’s organizational and scientific work in the State Optical Institute played a very important role in the development of the optical industry in the U.S.S.R.

BIBLIOGRAPHY

Rozhdestvensky’s Izbrannye trudy (“Selected Works”; Moscow-Leningrad, 1964) includes a list of his writings. On his life and work, see K. K. Baumgart, “Dmitry Sergeevich Rozhdestvensky,” in Pyatdesyat let Gosudarstvennogo opticheskogo institute (Leningrad, 1968); S. E. Frish, Dmitry Sergeevich Rozhdestvensky. Zhizn i deyatelnost (“…Life and Work”; Leningrad, 1954); and the notice in Lyndi russkoy nauki. Matematika. (“People of Russian Science. Mathematics”; Moscow, 1961), 303–313.

J. G. Dorfman