On the Electrodynamics of Moving Bodies.
By Max Abraham (Göttingen).
Meeting of January 17, 1909.
§ 1. Introduction.
It's known that the fundamental equations of the electrodynamics of moving bodies as stated by H. Hertz, which could be seen as the obvious generalization of Maxwell's field equations for resting bodies, are insufficient; they contradict the experiments conducted by A. Eichenwald and H. A. Wilson concerning the behavior of moving dielectrics.
Those experimental results are in agreement with the electrodynamic theories of H. A. Lorentz and of E. Cohn The heuristic ideas by which the two researchers were led, are mutually different throughout; while H. A. Lorentz starts from equations concerning the behavior of electrons and molecules, E. Cohn tries to establish the simplest description of electromagnetic processes in the sense of Kirchhoff.
The inconclusiveness of all attempts up to now, to discover an influence of Earth's motion upon the electromagnetic processes happening at Earth's surface, is satisfactorily explained by the theory of E. Cohn. On the other hand, the electron theory of Lorentz, which is based on the electromagnetic field in the aether, lays the view near at hand, that the motion of a system through the aether
- H. Hertz, Ober die Grundgleichungen der Elektrodynamik für bewegte Körper. 1890. [Gesammelte Werke, Bd. II, pp. 256-285].
- A. Eichenwald, Über die magnetischen Wirkungen bewegter Körper im elektrostatischen Felde [Annalen der Physik, Bd. XI (1903), pp. 421-441].
- H. A. Wilson, On the Electric Effect of Rotating a Dielectric in a Magnetic Field [Philosophical Transactions of the Royal Society of London, Series A, Vol. CCIV (1905), pp. 121-137].
- H. A. Lorentz, Versuch einer Theorie der elektrischen und optischen Erscheinungen in bewegten Körpern (Leiden 1895).
- E. Cohn, Zur Elektrodynamik bewegter Systerne. II. [Sitzungsberichte der Kgl. Preussischen Akademie der Wissenschaften (Berlin), Jahrgang 1904, pp. 1404-1416].