The Ritz-Einstein Agreement to Disagree
Robert S. Fritzius
A Shade Tree Physics on-line reprint of an article originally published in
Physics Essays (1990) 3, 371-374
Abstract: During 1908 and 1909 Ritz and Einstein battled over what we now call the time arrows of electrodynamics and entropy. Ritz argued that electrodynamic irreversibility was
one of the roots of the second law of thermodynamics, while Einstein defended Maxwell-Lorentz electromagnetic time symmetry.
Microscopic reversibility remains a cornerstone of our current paradigm, yet we are finding more and more evidence that experimentally discerned time arrows are asymmetrical and that they all point from past to future. This paper furnishes some comments about events leading up to the Ritz-Einstein confrontation, some subsequent developments, and an English translation of their agreement to disagree. A side by side comparison of two recent summaries of their battle communiqués is included to provide an overview of what they had to say about this current issue.
Maxwell built his electromagnetic field theory on ideas derived from classical mechanics, which was considered to be time reversible, but Poincaré, mentor to Swiss physicist Walther Ritz, observed that „…treatises on mechanics do not clearly distinguish between what is experiment, what is mathematical reasoning, what is convention, and what is hypothesis.“(1)
This paper is written from the viewpoint that microscopic time symmetry is an unproven convention that is still accepted as established fact and that we might find it beneficial to look under some old stones, one of which seems to have been buried.
In 1908 Ritz, who is well known for his work in spectral physics (the Rayleigh-Ritz perturbation theory and the Ritz combination principle) and his still widely referenced works on the mechanical vibrations of plates, produced a monumental, but not nearly as well known, criticism of electromagnetic field theory.(2a) Even though Ritz acknowledged that the Maxwell-Lorentz equations are elegant and are here to stay, his blockbuster conclusion (which was based, largely, on the inseparable ties of electromagnetic field theory to the discredited solid ether continuum), was this: „The partial differential equations and the notion of ether are fundamentally inappropriate to express the comprehensive laws for the propagation of electrodynamic interactions.“ (2b)
Ritz then enunciated his own preliminary time-asymmetric emission theory of electrodynamics (Part II of his work). He hypothesized that charged bodies continuously emit fluxes of fictitious particles, which travel at the speed of light with respect to their emission sources. These emission particles constituted a kinetic electrodynamic intermediate for retarded elementary interactions. He did not address absorption or scattering of his emission particles by other charged bodies, or even specify if he considered there to be more than one type of them, but he did indicate the need to account for their interactions with ponderable matter. For example, he admitted that this preliminary hypothesis was not compatible with Fizeau’s experiment on the entrainment of electromagnetic waves.(2c) According to Ritz, the Coulomb field is not a static state of space, but rather a kinetic particulate process, taking place in an otherwise empty space that has no properties of its own. His coulomb „interaction“ could be characterized as a revised form of the vector potential.
- 24. Mai 2013