Introduction

In our study of classical thermodynamics, we concentrated on the application of statistical physics to macroscopic systems. Somewhat paradoxically, statistical arguments did not figure very prominently in this investigation. The resolution of this paradox is, of course, that macroscopic systems contain a very large number of particles, and their statistical fluctuations are, therefore, negligible. Let us now apply statistical physics to microscopic systems, such as atoms and molecules. In this study, the underlying statistical nature of thermodynamics will become far more apparent.