D O C U M E N T 3 1 0 J U N E 1 9 2 6 3 2 5 health and it would no doubt also be good for Tete. Do you agree? You could per- haps even come along for a while if you are not worried about people’s talk it doesn’t bother me (due to complete hardening). Albert has written to me twice, but only when he wanted something from me, not from an inner need. I completely understand that. I did about the same when I was in roughly his situation. Tete’s letters give me much pleasure. I think it’s quite necessary that I be with him as often as possible during this time of stormy development for him. I hope I can visit with you on the trip to Geneva if you are still there. I’m traveling on 8 or 9 July. Tetel shouldn’t be angry with me for not writing to him. I am so pressed, that time and strength are insufficient. However, I am happy every day when I think about him. Warmest regards to you both, from your Papa 310. To Hendrik A. Lorentz [Berlin,] 22 June 1926 Dear and esteemed Mr. Lorentz, Until today I was thinking I might perhaps still be able to arrange to come and see all of you this month, in order to attend those interesting meetings with Klein. But now it doesn’t work anymore because I necessarily must finish up a few things before I go to my boys in Switzerland, which has to be at the beginning of July. Schrödinger’s method does look more like a real understanding than Heisenberg’s, and yet it is hard to insert a function into the coordinate space and regard it as an equivalent to a motion. If something similar could successfully be done in four-dimensional space, though, then it would be more satisfying. Mr. Rupp in Heidelberg has conducted a couple of experiments at my request on the light emission of moving canal rays. As you expected, everything comes out exactly according to the wave theory. In the hope of seeing you again soon in Geneva, I am, with kind regards to you and your wife, your A. Einstein P.S. The experiments by Miller are interesting, after all, although there is no reason to interpret the result as caused by a motion. It looks as if, apart from a constant terrestrial cause, a constant direction is making itself noticeable against the system of fixed stars. If this continues to be confirmed, something fundamental lies behind it. Planck and Laue are quite skeptical about this matter.