Lorentz Arguments for Ether: Critical Analysis of 1895 Paper

[Lincon Ribeiro]

TL;DR

Here is an excerpt from Lorentz's paper about relativity, when he had to explain his views about the ether and the bizarre results from Michelson & Morley experiments.

I bought the book "The principle of Relativity" by Einstein et al. and was really surprised by the (low) level of explanation by Lorentz regarding the compression of rods on the experiment carried out by Michelson & Morley. I reproduce part of it below:

Surprising as this hypothesis may appear at first sight, yet we shall have to admit that it is by no means far-fetched, as soon as we assume that molecular forces are also transmitted through the ether, like the electric and magnetic forces of which we are able at the present time to make this assertion definitely. If they are so transmitted, the translation will very probably affect the action between two molecules or atoms in a manner resembling the attraction or repulsion between charged particles. Now, since the form and dimensions of a solid body are ultimately conditioned by the intensity of molecular actions, there cannot fail to be a change of dimensions as well.

Well, he gave absolutely no arguments to back up that "molecular-forces-affected-by-ether" idea. That made me think if, by the time the article came up (1895), any physicist criticized the lack of evidences of his claims. The ether was a bizarre concept, as we all know today, with contradicting properties that could not be measured by any means.

 

[PeterDonis]

he gave absolutely no arguments to back up that "molecular-forces-affected-by-ether" idea

I wouldn't get too hung up on the term "ether". You can take the ether completely out of his argument and it is still a valid argument for why, when viewed from a fixed inertial frame, an object moving relative to that frame should contract in length. John Bell discusses this, IIRC, in a couple of the articles in Speakable and Unspeakable in Quantum Mechanics.

 

[Herman Trivilino]

Well, he gave absolutely no arguments to back up that "molecular-forces-affected-by-ether" idea.

Probably because he thought it too obvious to be worth mentioning. Molecular forces are electromagnetic forces, and the ether served as the medium for the propagation of those forces.

That made me think if, by the time the article came up (1895), any physicist criticized the lack of evidences of his claims.

I don't know. But I've read serious physics books that used the ether to make their points, and were written in the 1920's. It takes a long time for deeply-entrenched ideas to fade into history. In many cases it only happens when the physicists who continue to promote them finally expire.

 

[PeterDonis]

The OP question has been addressed. Thread closed.