VJAČESLAV ŽARDECKI

(1896 - 1962)

1. Biography. – Vjačeslav Žardecki was born on 16. April 1896, in Odessa (Russia) into a family of Polish origin. He attended and com pleted primary and secondary school in 1913 in Odessa, and graduated on the Physical-Mathematical Faculty at the Novorossia University, Odessa in 1917. He served for a time as a research assistant in the Astrophysics Department of this Faculty, but in January 1920 he left Russia and set tled in our country. In March of the same year he was appointed research assistant at the Belgrade Observatory, and in March 1921 he became as sistant in the Applied Mathematics Department at the Faculty of Phi losophy in Belgrade.

In March 1923, he successfully defended his doctoral dissertation On the Movement of a Solid Body along a Curved Line. Early in 1925 he became assistant professor of theoretical physics in the Applied Mathematics Department of the same Faculty. In 1930, he was appointed associate professor, and in 1939 he was promoted to the rank of professor of the same subject.

During World War II he was retired, and in 1943 went to the University in Gratz (Austria). In 1949 he moved to the United States and became professor of geophysics at the Columbia University in New York, where he died in 1962.

2. Teaching and textbooks. – Early in his teaching career, in 1927, the general curriculum and the courses of study at the Faculty of Phi losophy were reorganized. Theoretical physics became an independent subject and for the first time it was made compulsory for the students of physics. Zardecki held the following courses: theory of vectors, hydrome chanics and theoretical physics for the students of mathematics and physics (III—VI sem.). The second course – hydromechanics – was the first of its kind at the Belgrade Faculty of Philosophy, starting as of 1925. Throughout that time he also held a seminar in applied mathematics in collaboration with Prof. Milanković.

Žardecki wrote and published the following university textbooks:

a) Hydromechanics (lithography, printed copy), Belgrade 1932, and

b) Fundamentals of Theoretical Physics, Belgrade 1941. The former is the first textbook on hydromechanics for students of natural sciences, containing some 166 pages, which is primarily devoted to the mechanics of ideal fluids. The latter is the first complete course in theoretical phys ics at a higher mathematical level, containing some 400 pages, which ba sically comprises all the fields of theoretical physics.

3. Scientific research and papers. – The basic scientific fields in which Žardecki engaged and produced significant results are, above all, hydromechanics, astro- and geophysics, rational mechanics, and less importantly theoretical physics. Accordingly, his works can be classified in the following groups: a) Papers on rational mechanics, b) Papers on hydromechanics, c) Papers on astro- and geophysics and d) Papers on theoretical physics. The first group deals with various problems in the mechanics of systems and solid bodies and the second one studies different problems in the mechanics of ideal fluids, pertaining mainly to the problem of the Earth evolution. The third group continues and enlarges this problematics, with the applications to geophysical processes on the Earth surface, as well as the propagation and properties of the elastic waves in layered media, and the last one discusses some general questions in theoretical physics, in view of their conception and logical structure.

He also wrote three monographs: a) Mathematical investigations of the problem of the Earth evolution (1935), b) Theories on the shapes of celestial bodies (1958) and c) Elastic waves in layered media, with two coauthors (1957). They systematically present these problems, with a exhausive presentation and discussion of obtained results of numerous authors, including original papers of the author himself in these fields. Among the papers of Žardecki the most significant ones are those from the second and third group, pertaining to the fields of hydromechanics, astro- and geophysics, focusing in particular on the problem of the evolution of the Earth as a celestial body. In the above monographs the given results are obtained according to the hypothesis of the Earth zonal rotation, where it is assumed that in its original fluid state it was not rotating en bloc, but rather the different Earth zones had different angular velocities increasing from the pole to the equator. It should be stressed that, this theory has been accepted in scientific circles and provides satisfactory explanations of geophysical processes that occurred on the Earth, such as the separation of the continents and their movement, and the origin of the oceans and mountain chains.

Author: Mušicki, Đorđe