It’s not clear to me what you’re envisioning for M4.
The question is straightforward, predict what an accelerometer signal would show. For example, classically one expects to see the signal show near-constant recoil level during the time the small magnet travels through this inhomogeneous field, assuming it’s aligned. The situation is not necessarily the same in QM. If you expect the measurement to happen at the screen, you’d predict no signal until the spike at the moment of collision. Note that M4 is not necessarily the same experiment as M1.
the compass needle only pointing up or down doesn’t fit with the standard description what underlies Stern-Gerlach
Right, the setup is not exactly the same, but it determines essentially the same physical property,
The question is straightforward, predict what an accelerometer signal would show.
Reading Benja’s answers, I think my issue was that I thought “apparatus” referred to the accelerometer, not the large magnet used in S-G. Replacing that word with “large magnet” makes the intended question clear to me, and I see how to answer it with just QM.
The question is straightforward, predict what an accelerometer signal would show. For example, classically one expects to see the signal show near-constant recoil level during the time the small magnet travels through this inhomogeneous field, assuming it’s aligned. The situation is not necessarily the same in QM. If you expect the measurement to happen at the screen, you’d predict no signal until the spike at the moment of collision. Note that M4 is not necessarily the same experiment as M1.
Right, the setup is not exactly the same, but it determines essentially the same physical property,
Reading Benja’s answers, I think my issue was that I thought “apparatus” referred to the accelerometer, not the large magnet used in S-G. Replacing that word with “large magnet” makes the intended question clear to me, and I see how to answer it with just QM.