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vanhees71 said:
Which internal problems does the minimal statistical interpretation have
The minimal statistical interpretation (MSI) is incomplete in the sense that individual measurement outcomes exist, but MSI says almost nothing about them. It talks only about statistics when measurement is repeated many times. The fact that proponents of MSI do not mutually agree whether the Bell theorem implies non-locality (Ballentine thinks that it does, you think that it doesn't) shows that this incompleteness has consequences on conceptual understanding. Of course, this is not of much relevance for practical applications, but the point of interpretations is not to be relevant for practical applications.
 
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Demystifier said:
The minimal statistical interpretation (MSI) is incomplete in the sense that individual measurement outcomes exist, but MSI says almost nothing about them. It talks only about statistics when measurement is repeated many times. The fact that proponents of MSI do not mutually agree whether the Bell theorem implies non-locality (Ballentine thinks that it does, you think that it doesn't) implies this incompleteness has consequences on conceptual understanding. Of course, this is not of much relevance for practical applications, but the point of interpretations is not to be relevant for practical applications.

To me, the issue with the minimal interpretation is that it relies on a distinction between measurements and other interactions. To me, if measurement is definable in terms of more basic interactions, then claims about measurements are either redundant (since they're derivable from claims about the other interactions) or inconsistent. If measurement is not definable in terms of more basic interactions, then it seems to me that the minimal interpretation is incomplete, unless you add a separate theory of measurement.
 
DarMM said:
It'd be standard enough usage in papers on MWI and many papers on interpretations in general. I'm not going to claim one can derive standard phraseology from first principles logically, it's just the type of phrase that's ended up being used.

Also it is short in full for "There is a physical object described by the wavefunction with each component of the wavefunction corresponding to an aspect of that object, furthermore there are no more objects in existence aside from this"

It's certainly shorter than that.

How would you phrase it?
That is perfectly fine. Now you've added the part about the components, that makes it MWI specific. But to me it has a different meaning from "the wave function is the only thing that exists".
 
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Demystifier said:
I understand. But if you force yourself to chose one of the answers, can you then answer the other questions? And if you can, what are the two interpretations (one Copenhagenish and one ontological) that you finally arrive at?
I get consistent histories and shut up and calculate. But I have interpreted some of the questions in a way that may be different from what is intended.
 
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Demystifier said:
The minimal statistical interpretation (MSI) is incomplete in the sense that individual measurement outcomes exist, but MSI says almost nothing about them. It talks only about statistics when measurement is repeated many times. The fact that proponents of MSI do not mutually agree whether the Bell theorem implies non-locality (Ballentine thinks that it does, you think that it doesn't) implies this incompleteness has consequences on conceptual understanding. Of course, this is not of much relevance for practical applications, but the point of interpretations is not to be relevant for practical applications.
Well, that individual measurement outcomes exist is an empirical fact, upon which all our physics is based. Since the "randomness" of these outcomes are also an empirical fact and QT describes the corresponding statistics with astonishing accuracy, I don't see, where QT in the minimal interpretation should be incomplete. Measurements are defined by the apparati constructed to perform them. These devices are constructed using the known physics. Since the oustcomes of measurements are as expected (up to now) there's no additional theory of measurement necessary.
 
stevendaryl said:
Okay, to get an idea about your notion of "real", in General Relativity, is the spacetime manifold "real"? What's an example of something that it is meaningful to say is "real"?
No, the manifold is not real. The fields (the physical ones, not the mathematical ones) in the theory are real. For example the electromagnetic field, or dust, or fluids ect.
 
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vanhees71 said:
I don't see, where QT in the minimal interpretation should be incomplete.
How does QT in the minimal interpretation describe the state of the solar system?

We only have a single realization of the solar system, which has been prepared once in ancient times.
Hence we cannot apply rules that require a large ensemble of similarly prepared systems.
 
martinbn said:
I get consistent histories and shut up and calculate. But I have interpreted some of the questions in a way that may be different from what is intended.
Maybe this means that you should not worry about interpretations of those questions. Maybe this means that you should shut up and calculate consistent histories. :biggrin:
 
vanhees71 said:
Which internal problems does the minimal statistical interpretation have, despite...

Stephen L. Adler remarks in “Quantum Theory as an Emergent Phenomenon”:

“There are two conventional ways to try to avoid the measurement dilemma just stated. The first is to assert that quantum mechanics has only a statistical interpretation, and should only be applied to describe the statistical properties of multiple repetitions of an experiment, but not to any individual run. However, with the advent of our ability to trap individual particles for long periods, and to manipulate their quantum states (e.g., the particle emerging from the "up" beam in Fig. l d could be run into a trap, and manipulated there), this interpretation of quantum mechanics becomes dubious.”
 
@Demystifier

To avoid any "bias" regarding the "existence of the moon", there are two questions which should be asked:

- Is the moon there when nobody looks?

- Is the moon there even when somebody does look?
 
martinbn said:
No, the manifold is not real. The fields (the physical ones, not the mathematical ones) in the theory are real. For example the electromagnetic field, or dust, or fluids ect.

Well, I don't understand the criterion for considering something real or not from that. I would say that the spacetime manifold is as real as fields are.
 
Lord Jestocost said:
Stephen L. Adler remarks in “Quantum Theory as an Emergent Phenomenon”:

“There are two conventional ways to try to avoid the measurement dilemma just stated. The first is to assert that quantum mechanics has only a statistical interpretation, and should only be applied to describe the statistical properties of multiple repetitions of an experiment, but not to any individual run. However, with the advent of our ability to trap individual particles for long periods, and to manipulate their quantum states (e.g., the particle emerging from the "up" beam in Fig. l d could be run into a trap, and manipulated there), this interpretation of quantum mechanics becomes dubious.”

I don't think that asserting that "quantum mechanics has only a statistic interpretation" helps to avoid the measurement problem. The statistics predicted by quantum mechanics are statistics for measurement results.
 
Lord Jestocost said:
@Demystifier

To avoid any "bias" regarding the "existence of the moon", there are two questions which should be asked:

- Is the moon there when nobody looks?

- Is the moon there even when somebody does look?
If the answer to the second question is "no", what would be the corresponding interpretation of QM?
 
Demystifier said:
If the answer to the second question is "no", what would be the corresponding interpretation of QM?

Let me answer using Arthur Stanley Eddington’s words:
It is difficult for the matter-of-fact physicist to accept the view that the substratum of everything is of mental character. But no one can deny that mind is the first and most direct thing in our experience, and all else is remote inference ⎯ inference either intuitive or deliberate.
 
Lord Jestocost said:
But no one can deny that mind is the first and most direct thing in our experience
I deny that. Every baby has lots of experience of physical objects from which it learns to conquer the surroundings - but it takes a few years before it experiences mind.
 
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stevendaryl said:
I don't understand the criterion for considering something real or not from that.

This is a good illustration of why "real" is not a scientific term and why we generally disallow arguments about what it means.

Lord Jestocost said:
But no one can deny that mind is the first and most direct thing in our experience, and all else is remote inference ⎯ inference either intuitive or deliberate.

A. Neumaier said:
I deny that. Every baby has lots of experience of physical objects from which it learns to conquer the surroundings - but it takes a few years before it experiences mind.

And this is a good illustration of the kind of discussion about philosophy that we generally disallow.

Everyone, let's please keep this thread on topic. The topic is the flow chart posted in the OP. More general comments about philosophy and terminology are off topic.
 
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Lord Jestocost said:
Let me answer using Arthur Stanley Eddington’s words:
It is difficult for the matter-of-fact physicist to accept the view that the substratum of everything is of mental character. But no one can deny that mind is the first and most direct thing in our experience, and all else is remote inference ⎯ inference either intuitive or deliberate.
So I guess my solipsistic HV's could be a possible concrete version of this: https://lanl.arxiv.org/abs/1112.2034
 
PeterDonis said:
And this is a good illustration of the kind of discussion about philosophy that we generally disallow.

Everyone, let's please keep this thread on topic. The topic is the flow chart posted in the OP. More general comments about philosophy and terminology are off topic.

Excuse me, please! I wanted merely to point out that I am missing on the flow chart an interpretation which doesn’t conceptualize “observations” as “observations of things”.
 
Lord Jestocost said:
I wanted merely to point out that I am missing on the flow chart an interpretation which doesn’t conceptualize “observations” as “observations of things”.

Your post #105 didn't address that; it went off into philosophy land. If you think there's an issue with the flow chart, make a suggestion for how you would change it.
 
Lord Jestocost said:
check my post #101.

That doesn't say where in the flow chart you would put the second question. You can't ask two questions at the same time. Also, it doesn't say what the next flow chart steps are for the "yes" and "no" answers to the second question, or which interpretations the branches can end up at.
 
i ended up with statistical ensemble explanation (the moon is there if the universe is there) which reminds me of collective electrodynamics which was proposed by colleague of feynman as possible improvement of understanding light behaviour.
 
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PeterDonis said:
That doesn't say where in the flow chart you would put the second question. You can't ask two questions at the same time. Also, it doesn't say what the next flow chart steps are for the "yes" and "no" answers to the second question, or which interpretations the branches can end up at.

Question: “Is the Moon there when no conscious being observes it?”

a) Yes. b) No.

When answering “No”, the next question would be:

Is the moon there even when a conscious being 'observes' it?”

When answering "No", what we call 'reality' might just be a state of mind.
 
Videocamera is not a conscious observer for example. If we all look away from the moon and videocamera still records it then the question is resolved right? At least we could confirm that if no human is looking at the moon it is still there for a start.
 
Lord Jestocost said:
When answering “No”, the next question would be

Does this mean that if the answer is "Yes", we go to the next step in the flowchart as it is now?

Lord Jestocost said:
When answering "No", what we call 'reality' might just be a state of mind.

So, as @Demystifier already asked you, what QM interpretation does this correspond to?
 
PeterDonis said:
Does this mean that if the answer is "Yes", we go to the next step in the flowchart as it is now?

In case you think that it would make sense, you can go the next step with the "nonlocal collapse“ stuff.

PeterDonis said:
So, as @Demystifier already asked you, what QM interpretation does this correspond to?

If you absolutely want a name, call it the "radical idealistic interpretation".
 
Lord Jestocost said:
In case you think that it would make sense, you can go the next step with the "nonlocal collapse“ stuff.

What if I don't think it makes sense? Should there be another question in there? Or an alternative in the "nonlocal collapse" question that says something like "the question is meaningless"? And if so, what interpretation would that lead to?

Lord Jestocost said:
If you absolutely want a name, call it the "radical idealistic interpretation".

You're not supposed to just make up your own interpretation. I'm asking whether there is a recognized interpretation in the literature that corresponds to this branch of the flow chart you are proposing.
 
PeterDonis said:
You're not supposed to just make up your own interpretation.

With all due respect, what is actually your problem? I never intended to make up my own interpretation. I merely wanted to point out that one can – to say it in a simple way - adopt a solipsistic point of view when reasoning about questions like “Is there a moon…?” or “Is there an electron …?” and so on. A mere addition to the flow chart.