D O C U M E N T 1 2 7 D E C E M B E R 1 9 2 5 1 4 9 However, I must note that the first part, , is not a pure gravitation tensor already the simple example of the spherically symmetric solution shows that it con- tains the charge.[6] Regarding the unification of the field equations, the matter does not look as sim- ple. What had formerly appeared to be the field equations of gravity, namely, , can now be regarded as the condition for the vanishing of the electromag- netic field hence the ansatz no longer appears as ¢an ansatz for² a law but as the result of neglecting the elec- tromagnetic field. The matter is by no means dealt with because of the above, but I am not going to take up any more of your time. Respectfully yours, G. Y. Rainich 127. From Heinrich Zangger [Zurich, before 10 December 1925][1] Dear Friend Einstein, I’ve just heard that I will soon receive a letter from you in which you inform me of your opinion about your son Albert—& give me instructions as to what I should discuss with Albert.[2] I will gladly do that, but must leave about 10 Dec. to hopefully restore my health this winter [3] so I must ask you to write soon what you think in order to still have time. In the same letter you could also inform me what’s new and good that I should read in the mountains. You have a good nose and you sit next to and sniff out the sources. Dr. Dällenbach[4] has now ventured something that means a great financial risk, but will perhaps succeed: He has founded a construction & research company (for technical physics) & is first building a new rectifier (unfortunately isolated from the technology). All the good people from Brown-Boveri have gone over to the new company with him.[5] But I am worried, since he has assumed responsibility for a large amount of capital and has the big corporate groups as opponents. General Electric foolishly did not accept him (as now Brown-Boveri has become the competitive company in Amer- ica). I’m writing that to Whitney in Schenectady, whom I know well.[6] I’m afraid Weyl is going to Leipzig. Healthwise, he’s been doing quite well in recent years.[7] I apparently did well to keep him here at least now he can move Gij, kl Rij 0= Eij kl , 0= Rij 0=
Previous Page Next Page