Not in his preferred interpretation. Or can you quote him saying exactly this?vanhees71 said:
That's a very appealing statement, thanks. Of course it will get you into trouble.vanhees71 said:
I quoted him above in #49. The scan is from Ballentine's famous RMP paper where he explains the minimal statistical interpretation in detail:martinbn said:
Yes, and he clearly says that the state represents an ensemble not an individual system!!!!!!!!!!!vanhees71 said:
But this doesn't say that the state is of an individual system. The preparation procedure produces many systems. And the state describes the ensemble, not the individuals. I think you need to read it carefully.vanhees71 said:
You're going to hate this: What do you make of the distinction between a preparation procedure, and the result of a preparation procedure?vanhees71 said:
I don't object to the use of a phrase like "finite ensemble", but my understanding is the "ensemble" in ensemble interpretations is necessarily infinite. Ensemble interpretations attempt to overcome apparent ambiguities when discussing individual systems, and a statistical sample is still, in a sense, an individual system (e.g. see this post of mine). Any statistical sample/finite ensemble falls back into the trappings of quantum theories of individual systems.vanhees71 said:
But maybe the trappings of ... individual systems are not so bad overall, as long one is sufficiently careful to apply "good taste":Morbert said:
gentzen said:
gentzen said:
Wait, I just see that you quoted from a very long sentence of mine here:PeterDonis said:
OK, I see that my sentences seem to be much too long. I will try to work on it. For me, the meaning of the quoted part changed significantly by leaving out the "before you know" part. And stripping away an "if ... then" part in general also risks to change meaning. However, I would also have stripped it away in this case, because it didn't impact the meaning.gentzen said:
maybe not important, but this parenthetical clarification is not helpful for mevanhees71 said:
The description of a state and a preparation procedure was helpful. But the text in the parenthesis behind the word "observation" doesn't make sense to me.vanhees71 said:
No, you just have to read what they actually say instead of what you would like them to say.vanhees71 said:
That's not what Ballentine says. Ballentine says the ensemble is not the actual group of actual systems that are prepared by some preparation procedure. It is the abstract set of an infinite number of abstract systems that could be prepared by that preparation procedure.vanhees71 said:
This is unrelated. You were making claims about Ballentine's interpretation, which were wrong.vanhees71 said:
The quote is not wrong. Your statements are. You write "for a single elctron the state represents". Ballentine clearly says that the state represents the infinite abstract ensemble. You are wrong when you claim that Ballentine says what you say. He does not. Thr two of you use different interpretations. Yours is a Copenhagen interpretation in the way Bohr uses it.vanhees71 said:
No, vanhees71's interpretation is not a Copenhagen interpretation, independent of whether he adheres exactly to Ballentine or not.martinbn said:
Why not? Where does he differ?gentzen said:
The statistical interpretation falls in group (I) from the quote, and yours in group (II).vanhees71 said:
At many points. He accepts neither the role of classical concepts in Bohr's thinking, nor the collapse of the wavefunction as an update of knowledge in Heisenberg's thinking. And your claimmartinbn said:
feels strange to me. When has vanhees71 ever asserted that "a pure state provides a complete and exhaustive description of an individual system (e.g., an electron)"?martinbn said:
My interpretation falls in group I, because for me all the state describes concerning the properties of the systems prepared in a state are the statistical properties, which of course refer to an ensemble of equally prepared systems. I just say the same as what Ballentine says with different words.martinbn said:
What you actually mean here is that the phrase "single electron" occurs in the passage in question from Ballentine's book. But it occurs in the context of describing an ensemble, which, as Ballentine makes clear, is not the same thing as the real collection of real electrons that get prepared and measured in real experiements. So you are taking Ballentine out of context when you claim that his use of the phrase "single electron" means that he takes the quantum state or the preparation procedure to apply to real single electrons in real experiments. Read in context, that is not what he is saying.vanhees71 said:
Perhaps you think you do, but nobody else here appears to agree.vanhees71 said:
Sure you can. Ballentine describes how: you treat the real world statistical sample as just that, a statistical sample from the abstract ensemble that the formalism describes. Then you use standard statistical techniques to see how well the statistical sample matches what you would expect from the abstract ensemble.vanhees71 said:
Yes.vanhees71 said:
Yes.vanhees71 said:
The state can be taken to refer to the preparation procedure, but if you take the state this way, it refers to the preparation procedure as it applies to the ensemble, not as it applies to an actual single electron in an experiment. The state is part of the mathematical model, not part of what you compare the model's predictions to. The actual preparation you do in the experiment, and the actual electron you do the preparation on, are part of what you compare the model's predictions to.vanhees71 said:
