Einführung in die Dynamik von Sternsystemen

Abstract

THE subject of stellar dynamics is concerned with the general properties of the motions of assemblages of stars. Just as in gas theory it is not possible to follow the motions of individual molecules, but the properties of the motions of all the molecules are discussed by statistical methods, so in stellar dynamics it is not the motions of individual stars that are of interest but the general statistical properties. An assemblage of stars moving under their mutual gravitation is not, however, analogous to an ordinary gas, for collisions are practically non-existent ; the effect of close encounters is to cause a slow approach toward equipartition of energy; but it can be shown that the time required for equipartition to be attained is of the order of a hundred times larger than the ages of the stars on current views. The motions of stars are therefore analogous to those of molecules in a gas theory where there is a gravitational potential but no collisions.

Einführung in die Dynamik von Sternsystemen

Von Prof. Dr. E. von der Pahlen. (Lehrbücher der Monographien aus dem Gebiete der exakten Wissenschaften, 10; Astronomisch-geophysikalische Reihe, Band 1.) Pp. 240. (Bern: Verlag Birkhäuser, 1947.) 36 Swiss francs.