The New Statistical Mechanics

HIS is the second article upon statistical mechanics which I have published this year in this Journal. The first, which appeared in the January (1)43) issue, was devoted to the oldest form of the theory, which is variously known as the old, the classical, or the Boltzmann statistics. The word "statistics," I repeat from the former article, is a synonym for statistical mechanics, objectionable but (because of the length of the alternative) hardly to l»e avoided. The "new statistics," frequently divided into "the Hose-Einstein statistics" and "the Fermi-l)irac statistics," emerged in the middle twenties and ever since it has been gradually pushing its ancestor aside. In .his article I propose to expound the new statistics, laying especial emphasis 01 the theory of monatomic gases, to which the former article was strictly limited.