Electromagnetic Things in 1890

So, by 1890, Hertz had found electromagnetic waves and noticed the photoelectric effect.  Phillip Lenard worked on the photoelectric effect and other cathode-ray-centric phenomena and won the Noble Prize for that work in 1905.  Here is his apparatus for producing photoelectric effects:

Definitely looks like it could have produced some rays.

Meanwhile, how was the world of electromagnetic theory – apparently fully “classical” by sometime in the late nineteenth century – doing?  I’ve already suggested that the whole fantastically elaborated aether thing was more a symptom of a prolonged crisis than the sign of any stable “classical” theory – but how was classical theory doing in 1890?

According to Buchwald (at around page 176 in From Maxwell to Microphysics) it was in its usual “classic” state of complete flux and total confusion.  Theorists outside of the Maxwellians in Great Britain had heard of Hertz’s “striking confirmation” of something Maxwellian with his waves, but (except for Willard Gibbs in the US and maybe August Otto Föppl in Bavaria) no one outside of the Maxwellians actually understood Maxwell because, for Maxwellians, electricity was a by-product of field processes and for other theorists the view (which had not changed since the 1840s) was that electricity was “not an epiphenomenon, but an entity in its own right.”

Still, by 1899, classical electromagnetic theory had attained a year of relative stability, based on the electron (which, as we will see had become necessary by 1894 before it was officially discovered as “corpuscular particles” by J. J. Thomson in 1897), the aetherial continuum for fields and some ways of connecting the aether and other things as well as accounting for why the aether was not very easy to evaluate or even define.  Even this limited stability was going to get wobblier very quickly since Planck was about to discover that the continuum fields had to support discontinuous energy states and Einstein was reading Föppl.

As Phillip Lenard perhaps groaned privately, “He who has not felt horror and vertigo when considering Classical Physics has not seriously looked at Classical Physics.”  Nevertheless, in his tubes of rays, Lenard had indeed seen something very strange and not very classical.  And something that still haunts us, maybe, sort of.

Here is a photo that seems to be of Föppl (or someone with a Föppl-esque beard) at the Technical University in Munich with some students:

Aethers, for the planets to swim in

For my first project in this new run of Cold War Kitchen, I’ll move away from Russian Installation Art.

And take a look at some experimental programs in physics and their associated Phenomenology and procedural formalisms in the period 1870 -1930. 

Originally, I thought it would make sense to jump straight to Mesons and Cosmic Rays in the 1930s, but I found some interesting sources on X-rays and electrons – particularly how difficult it was to wrap up the impact of the notions of photons and quanta, so I started looking at the situation around 1900.  There it seemed the electron had been buzzing through some problematic space since around 1870 and the key element of change in thinking about the electron (or cathode rays or corpuscles or charges etc.) was the relatively rapid disappearance of ideas about the aethers, which are definitely gone from the experimental world by 1930, though (as I hope to show in later posts) there were still aether-style assumptions in some central phenomenologies as late as the mid-1920s.

So, just to get an initial perspective on the Aethers, as the nineteenth century opened, there could be a lot of them in circulation.  For example, Etienne Geoffroy Saint-Hilaire, in 1801, working feverishly with electric fish under bombardment in Alexandria, invoked five aethers or “imponderable fluids,” each carrying a different kind of energy.  He used these aethers in his visionary description of what he was seeing in his fish under bombardment: the nervous fluid, the caloric, the luminiferous, the electrical and another one for sound. ( see pages 77-78 in Toby A. Appel’s The Cuvier-Geoffroy Debate). Of the five imponderable fluids used in his description of the physiology of electrical fish, only one – the carrier of sound – was viewed skeptically by the savants of the day.  As nineteenth century science moved on from catfish and eels to electromagnetism, skepticism about the aethers began to accumulate even as they became integrated into Victorian culture to the point that the aethers became practically mystical and metaphysical necessities.  So (as Wikipedia notes in the article on luminiferous aethers) by 1878, most skeptically, Maxwell would write of the aetherial excesses of the recent past:

 Aethers were invented for the planets to swim in, to constitute electric atmospheres and magnetic effluvia, to convey sensations from one part of our bodies to another, and so on, until all space had been filled three or four times over with aethers. … The only aether which has survived is that which was invented by Huygens to explain the propagation of light.

And that is the point where this blog takes up the story: 1878 – just after observation of the Kerr effect – that is, the multiple effects of changes in magnetic fields on the polarization of reflected light (Faraday had already noted a rotation of polarization caused by a magnetic field in 1845).