1911 Solvay Conference Einstein

 Back in 1911 there was a scientific conference in Europe, invitation only, that brought together some of the giants of early modern physics: Curie, deBroglie, Einstein and 15 more. The topic was 'Radiation and Quanta', Einstein only 6 years earlier in his miracle year introduced light quanta to explain the photoelectric effect. In 1911 quantum mechanics was still a decade away, the fundamental contributions of Schrodinger and Heisenberg were yet to come. 

I bring this up for two reasons. First, I recently watched the movie Copenhagen about the 1941 meeting of Heisenberg and Bohr on the eve of nuclear weapon development by both sides of the war. The movie reminded me of a recent book auction where the 1912 Proceedings of the first Solvay conference went out of reach at $700 and I dropped out of the bidding. I immediately had remorse, thinking 'how often do you get a 1911 Einstein publication on quanta, let alone the other luminary contributors?' That set me searching online and I found exactly two copies for sale, one at $5000 and the other at $250. Such gems are thinly traded, thinly understood by book collectors, and you can get this kind of enormous stretch. 

My 1912 first edition copy of the proceedings arrived today. It is in French of course, the only other early edition being in German 2 years later. I own very few non-english books because, big surprise, as an American I only speak/read English. But things progress in the world and here is a prime example. It turns out there is a Google Translate app for the iPhone and it can import a page photo and translate the text on the page. This works for many language pairs, including French to English. Below is an image of page 439 of the proceedings, a page in Einstein's presented paper. Not a great photo, but good enough. Here is the translation via the google-phone method:

"Such a hypothesis does not necessarily require a disagreement with the conservation of energy since one always has the possibility with admitting it is an accumulation of the difference between the two energies, incident and absorbed.  However, it would be necessary to form an explanation of the mechanism of such an accumulation as well, which, probably, would be no less difficult than to imagine a considerable irregularity in the distribution of radiant energy.  

     If one rejects this hypothesis of accumulation one must resolve to abandon the law of conservation of energy in its present form, for example by attributing only statistical validity to it, as is already done for the second principle of thermodynamics.  Who would have the courage to make such a decision?  

     I have had no other objective here than to show how fundamental are the difficulties in which the formula for radiation leads us, even if we consider it as a simple datum of experience.  

 

III APPLICATION OF THE QUANTA HYPOTHESIS TO GENERAL FACTS.  

 

The result of the previous paragraph can be summarized as follows: when a body exchanges energy by a quasi-periodic mechanism of frequency v, the statistical properties of the phenomenon are the same as if the energy moved by integer quanta of size hv.  

     Although we do not see by what mechanism this property can be explained, we must admit in any case that the disappearance of periodic energy must be done by quanta."

 

Einstein speaks again, in English, from 110 years ago. If you are curious about the scope and impact of the First Solvay Conference, here is wonderful review.

Happy new year.