Chapter 52 - Heinrich Hertz, posthumous book on mechanics (1894)

Abstract

Offering a mechanical foundation of physics that avoided force as a basic concept, Heinrich Hertz's Posthumous Book on Mechanics was the first book on mechanics to make use of Riemannian geometry in configuration space. One of the main problems that were up for debate was the role of unobservable atoms and molecules and the forces at a distance assumed to act between them. A group of positivist and phenomenologically oriented physicists and chemists believed that if physics was based on a concept of energy, it could be possible to avoid making appeal to unobservables and forces at a distance. Hertz referred to many logical problems encountered in usual mechanics, and he concluded that the concept of force was to blame for most of them. Most reviews listed the following merits: its philosophical sophistication, its rigorous mathematical structure, its avoidance of forces, and its intuitively pleasing formulation of the fundamental law of motion. As its main weakness most reviews mentioned, it is the complete neglect of the problem of how to account for the actual motion of even simple systems in nature, such as those that the usual image of mechanics describes by way of forces.