D O C U M E N T 2 0 0 M A Y 1 9 2 2 1 7 3 Each atom is always directionally quantized—no matter where it is. In transit from one field into another (even from an electrical one into a magnetic one), each quantum state changes adiabatically into another state but into one that again obeys the spatial quantum condition. So each atom in the solid body is already direction- ally quantized or bonded with other atoms in such a way that upon vaporizing within a field it is directionally quantized. There aren’t supposed to be any degen- erated states in the true sense. Consequently, from the outset the vaporized beam is completely directionally quantized, hence also in a (strong) field. The statistical distribution among the quantum states is determined by the distribution in the solid body and corresponds to its temperature, taking into account that only in the solid state can sufficiently frequent jumping between quantum states occur. Our calculation[2] is valid for the transition between quantum states through radiation. It has no practical significance, however, because the experiment cannot give any information about its validity or invalidity. If it were possible to magnetize the vaporizing body far beyond the proportionality limit, the one quantum state in the vapor beam would degenerate at the expense of the other. Of course I do know that objections to this consideration exist. If such a silver vapor is in a weak magnetic field and prior to a collision two atoms are directionally quantized, then, as I see it, after the collision they should also be that way. Because the magnetic field is arbitrarily weak compared to the forces exerted during the col- lision between the atoms, it is hard to believe that the nonquantization doesn’t get into some disarray in the process. At this point I can just say: The dir[ectional] q[uantization] of an individual mol[ecule] during collis[ion] is defined by the strong forces, but the transition to freedom takes place as if it happened infinitely slowly. [. . .] the adiabatic processes, which do not happen infinitely slowly. Now, I don’t know whether we should publish our notice yet.[3] In any event, not while a controversy exists between us. If we cannot clarify it enough for the two of us to reach agreement, then it’s better if we let it be. Yesterday I spent the entire evening with that magnificent Joffe,[4] throughout which we kept strictly to the agenda but did not manage to finish up nonetheless. His analyses on the conductivity of crystals interested me very much.[5] What’s going on with Breit’s hypothesis about superconductivity? That interests me.[6] Joffe definitely promised to write to you yesterday. He smiled so nicely as he recalled his sins. Cord. regards to all of you, yours, Einstein.