On Tuesday, October 8, 2024 at 12:27:19 PM UTC-6 Alan Grayson wrote:
On Tuesday, October 8, 2024 at 10:30:43 AM UTC-6 John Clark wrote: On Tue, Oct 8, 2024 at 10:12 AM Alan Grayson <[email protected]> wrote: *> It could mean the system is in one of the states of the superposition, but we don't know which one;* *Yes, it could be that the electron was in one and only one state before the measurement was made and we just don't know which one. If that is the case then realism is correct and, to be consistent with experimental results, either determinism or locality or both must be wrong. You just can't have realism and localityand determinism, you've got to abandon at least one of those three things.* *Could you explain why this is the case, if it is? TY, AG * * >OR, as in the Stern-Gerlach experiment, it's not in any of the states of the superposition before measurement!* *Yes It could be that it was not in any one particular state before a measurement in which case realism would be wrong, or it could be that it was in all possible states before a measurement in which case realism is also wrong. For realism to be correct it would have to be in one and only one definite state before a measurement was made.* *In SG. the electron is an undetermined state before the measurement, and the measurement might force it into UP or DN spin, or reveal its state before measurement. We just don't know, and more important IMO, we can't know. All we can do is measure and acknowledge the result. This is what Schrodinger established with his cat experiment, EXCEPT that he went further -- in establishing we know the state before opening the box is not alive and dead simultaneously while the box is closed. So, in general, it's impossible to say anything about a superposition EXCEPT that we know nothing about the state of the system before measuring it. So, there's really no possible test for realism or its denial. In the case of MW, you're assuming a great deal about a system's state before measurement, but you (and the other "experts" you've referenced) have no logical basis for that assumption. AG* *Let me clarify my above comment. What Schrodinger established, is that we know that a system in a superposition cannot be assumed to be in all states of that superposition simultaneously before the measurement. He constructed a counter-example to that assumption. That is, the assumption is not guaranteed to be true. All we really know, via the postulates of QM, is that the superposition states are possible states of the system after measuring it. AG* > *he's referring to results of Bell experiments, which ostensibly deny realism.* *The falsification of Bell's Inequality does not mean realism must be wrong, it means that realism might be wrong, and if it's right then determinism or locality or both must be wrong. * *But, as I stated above, IMO we can't know if realism is false. I thought Bell experiments falsified realism, but you say otherwise. Now I am not sure if you are correct, but you might be. AG * *> Copenhagen doesn't explain the collapse of the wf as a dynamical event. I view it as a bookkeeping device* *Yes, and some people, perhaps even most people, don't even try to explain the ambiguities in Quantum Mechanics and are content with the "Shut Up And Calculate" philosophy** (a.k.a. the Copenhagen interpretation) ;** and that's fine if you're an engineer and are only interested in making sure you get the right reading on your voltmeter. Personally I'd like a little more but there is no disputing matters of taste. * *I do not embrace that philosophy. Definitely not. I think we should keep thinking about the problem, and perhaps, some day, a solution will be found. But since that day isn't today, it's foolish for those who assume the solution has been found - namely, that superposition implies a system is in all states simultaneously before (underline added) the measurement -- to go off assuming MW or whatever, based on a presently, and possibly forever undecidable proposition. AG * -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/everything-list/bc9814e2-0026-4df7-aaa4-938d749585den%40googlegroups.com.
