The quantum state cannot be interpreted statistically?

[Ken G]

And now the interesting questions:

1. Does PBR support the spirit of this view?
2. Which interpretation of QM is most consistent with this view?

1. I'd say the issue here is what is in a "structure." The structure of all theories is to afford systems with properties, and interpret those properties as determining the system behavior. The trouble is, there seems to neither a unique way, nor an exact way, to do that. Thus the structural realist becomes a naive realist as soon as they extrapolate their faith in structure beyond what is actually present in the theories. I cry "foul" as soon as anyone who purports to structural realism reverses the direction of the logic of that stance-- the stance says that our theories represent or mimic in some way the actual structure that is there, but it never says the converse, that reality represents or mimics our theories. So no matter how well the concept of a property does in making correct predictions and organizing our thinking, and no matter how well the structure of these properties can mimic or reflect in some way what is actually happening, it's never going to mean there really are any such properties, or indeed any such thing as properties, in a reality that does not have us in it.

As for which interpretation of QM is most consistent with structural realism, I'd say they are all equally consistent, because they all focus on some kind of successful structure in the interpretation. This is very much my point-- structures are not unique.

 

[Len M]

2) structural realism-- the properties of our theories are just what we can demonstrate them to be: properties of our theories. However, they must work for some reason, to whatever extent they do work, so we'll say that they work because they share some vague "structural similarity" to the actual reality, whatever that means.

2) This one is at least logically self-consistent, but is pretty vague. I view it as basically correct, but only because it is not saying much. It's main purpose is to reassure ourselves that we have good reason to speak in ontological language, but in fact the real reason for doing that is simply because it is convenient. This convenience is what I meant by it being "a given" that scientists are going to invoke ontological language, and hence adopt a form of scientific realism, the issue is merely how literally will they take themselves.

I’m in favour of (2). I agree the relationship to actual reality is vague (it has to be because the scientific method is not applicable to mind independent reality), but what the notion does is to place existence before knowledge. Pure idealism does not, it places knowledge before existence.

That’s just a philosophical point I know, but for me it’s important, because accepting the notion of mind independent reality as having a connection (however vague) with properties of our reality gives a plausible philosophical argument against pure/radical idealism

 

[Ken G]

Yes, I agree-- to me, the defining character of realism is just the idea that reality leads to our understanding, rather than the other way around. That's exactly why I argue that naive realism is actually much closer to idealism, because it involves imagining that the reality is very close to what is happening in our minds, but then it's a small step to idealism where the reality is what is happening in our minds. You just can't have it both ways, maintaining a wide berth from idealism means being skeptical of the connections between our theories and true reality. Unfortunately, that is not the way the term "realism" is normally applied, which I believe is the source of much of the difficulty around applying that term in a logically self-consistent way.

 

[bohm2]

So no matter how well the concept of a property does in making correct predictions and organizing our thinking, and no matter how well the structure of these properties can mimic or reflect in some way what is actually happening, it's never going to mean there really are any such properties, or indeed any such thing as properties, in a reality that does not have us in it.

I was reading through Leifer's comments section and I'm not sure if this is accurate but Norsen argues this point:

Psi being "ontic" doesn’t mean that psi is among the beables postulated by the theory; it just means that it is a function of the posited beables.

So Norsen, if I'm not misinterprerting him, is arguing that PBR is theory-relative and isn't making any metaphysical claims? By "properties" PBR mean with respect to theory not with respect to mind-independent reality (metaphysical claim)?

 

[Fredrik]

So Norsen, if I'm not misinterprerting him, is arguing that PBR is theory-relative and isn't making any metaphysical claims? By "properties" PBR mean with respect to theory not with respect to mind-independent reality (metaphysical claim)?

The mathematical part of the PBR argument certainly doesn't say anything about properties being a part of "mind-independent reality". But the statements the authors make on page 1 strongly suggest that they think of "properties" as the theory-independent reason why our theories work.

You have brought up the fact that different people interpret the PBR article differently a couple of times. I think this is perhaps the main reason. To me, the comments on page 1 are completely irrelevant. They might as well not be a part of the article. Only the statement that can be proved mathematically deserves to be called a "theorem" anyway, so I don't care how the authors (mis)interpret the significance of what they can prove. Ken G on the other hand seems to care only about the things they said in plain (non-mathematical) English.

 

[bohm2]

The mathematical part of the PBR argument certainly doesn't say anything about properties being a part of "mind-independent reality". But the statements the authors make on page 1 strongly suggest that they think of "properties" as the theory-independent reason why our theories work.

This is from page 1 of PBR:

Our main assumption is that after preparation, the quantum system has some set of physical properties. These may be completely described by quantum theory, but in order to be as general as possible, we allow that they are described by some other, perhaps undiscovered theory. Assume that a complete list of these physical properties corresponds to some mathematical object, λ.

Isn't this analogous to Bell's assumptions where Norsen writes:

But this attitude fails to appreciate one of Bell’s important advances – namely, that his formulation of local causality is a criterion for assessing the locality of candidate theories. As already discussed in Section II, Bell’s “complete specification of beables” simply does not mean a specification that captures everything which in fact really exists; rather, it means a specification which captures everything which is posited to exist by some candidate theory. There is thus nothing the least bit metaphysical or obscure about Bell’s requirement. For any unambiguously formulated candidate theory, there should be no question about what is being posited to exist...There will of course still be difficult questions about how to decide whether a given candidate theory is true, and hence whether the particular sort of non-local causation contained in it accurately describes some aspect of Nature. But the miracle of Bell’s argument is that we need not know which theory is true, in order to know that the true theory (whatever it turns out to be) will have to exhibit non-local, super-luminal causation

.

http://lanl.arxiv.org/PS_cache/arxiv/pdf/0808/0808.2178v1.pdf

So in both "theorems" the assumptions are talking about properties of theories?

 

[Fredrik]

In that page 1 quote, they assume that systems have properties, and then they say that those properties may be described by QM or by some other theory. To me that suggests that they consider the properties to be more fundamental than the theories.

Consider what I said about ontological models for quantum theories here:

...a set $\Lambda$ whose members are called ontic states. The members of $\Lambda$ are assumed to satisfy an equality like $$\sum_{\lambda\in\Lambda} P(\lambda|\psi)P(k|A,\lambda)=|\langle k|\psi\rangle|^2.$$ This exact notation is only appropriate when $\Lambda$ is finite, and the ontological model is non-contextual, but it's sufficient to illustrate the general idea. This requirement makes it convenient to think of

• $\lambda$ as a complete specification of all the properties of the system,
• $P(\lambda|\psi)$ as the probability that the system has properties λ, given that the preparation procedure is consistent with $|\psi\rangle$,
• $P(k|A,\lambda)$ as the probability that the result will be k, given that the properties of the system are λ, and that the measurement procedure is consistent with A.

The function $\lambda\mapsto P(\lambda|\psi)$ is called the epistemic state associated with the equivalence class of preparation procedures that the quantum theory associates with $|\psi\rangle$.

The way I see it, there are two ways to think about this. Either that formula holds because λ represents properties, or that formula just makes it convenient to think about λ as representing properties. It seems to me that P, B & R have chosen the first option, while the person who wrote the Stanford quote in #419, and the person who wrote the stuff in your last quote, would choose the second.

 

[qsa]

Yes, I agree-- to me, the defining character of realism is just the idea that reality leads to our understanding, rather than the other way around. That's exactly why I argue that naive realism is actually much closer to idealism, because it involves imagining that the reality is very close to what is happening in our minds, but then it's a small step to idealism where the reality is what is happening in our minds. You just can't have it both ways, maintaining a wide berth from idealism means being skeptical of the connections between our theories and true reality. Unfortunately, that is not the way the term "realism" is normally applied, which I believe is the source of much of the difficulty around applying that term in a logically self-consistent way.

Are you denying that nature has ontic character, even if all we can do to describe it, is a mind-dependent description. And how do you prove that since you already limited yourself early on. Or maybe I am not interpreting you idea correctly.

 

[my_wan]

I don't actually think that (2) and (3) are separable in terms of what claims we can scientifically substantiate, they are only different in terms of how we frame what science is about. There's a tradeoff between what we can demonstrate science is about, versus what we'd like to think science is about, and the order of the three goes from overly stressing the latter to perhaps overly stressing the former.

What science is about is a synthesis of that which we can substantiate to maximize predictability and innovation. To a priori drop (2), on the grounds that (3) is ultimately what it constitutes, undermines the very thing science is given that definition.

Are you arguing that we should "frame" science as something which science then must ignore what it is defined to be in order to potentially gain breakthroughs in the maximization of predictability and innovation? What is the point in this?

 

[Ken G]

Are you denying that nature has ontic character, even if all we can do to describe it, is a mind-dependent description.

No. Asserting that nature has ontic character is all that I think "realism" should mean. However, the standard meaning of the term is much more-- it holds that the ontic character of our theories (the "beables" of the theory) correspond exactly (in the case of naive realism) or in some structural way (in the case of structural realism) to the ontic character of reality. The first I consider pretty silly (at best it forces us to tell the difference between a beable that is not real and one that is, and resorting to the time-honored approach of saying that yesterday's beables were not real, but today's are, is clearly unsatisfactory). The second is reasonable but doesn't say much because it's not clear just what "structure" we are even talking about. But my fundamental claim is that if there is something that is impossible to talk about scientifically, then that thing does not even exist scientifically. So if we say "we can only talk about the ontic character of nature in a mind-dependent way", then there just plain isn't any scientific meaning to the mind independent ontic character of nature. Bohr already said it-- physics is not about nature, it is about what we can say about nature.

 

[Ken G]

What science is about is a synthesis of that which we can substantiate to maximize predictability and innovation. To a priori drop (2), on the grounds that (3) is ultimately what it constitutes, undermines the very thing science is given that definition.

I agree, that's why I never said to drop (2) in favor of (3). I think instrumentalism goes too far, it strips science of too much of its meaning just to have the benefit of being completely concrete. I would say that (1) is what every scientist in effect does in their daily progress but cannot justify as anything but convenience, and (3) is the only thing any scientist can really justify as actually true, but (2) is the compromise that gets something of the best of both worlds without being internally inconsistent.

Are you arguing that we should "frame" science as something which science then must ignore what it is defined to be in order to potentially gain breakthroughs in the maximization of predictability and innovation? What is the point in this?

I'm saying we should frame science as just what science is, and stop pretending it is something else. In particular, we should stop pretending that because theories invoke properties to great advantage, this means that the ontology that properties invoke is anything but a pretend ontology that we use as a convenience for doing science. The connection to a real ontology, if any such thing even exists, is both vague, and unnecessary to specify, to do science, so why not just accept this truth? When one does accept this truth, the idea that a property could determine the outcome of an experiment is dubious. A property of a theory can determine the prediction of a theory, but the PBR theorem is not about how to use QM to make a prediction, it is about what kinds of backstories we can tell about quantum mechanics that will be consistent with whatever brand of realism we are trying to make consistent with quantum mechanics.

 

[Ken G]

The mathematical part of the PBR argument certainly doesn't say anything about properties being a part of "mind-independent reality". But the statements the authors make on page 1 strongly suggest that they think of "properties" as the theory-independent reason why our theories work.

Yes, I'm a bit unclear about the role of that thinking in making the proof go through, or if it is just the importance of the theorem that is relevant to their interpretation of what properties are. Certainly, the blogs about the importance of the theorem are all about the "plain English" part, not the mathematics of the theorem. Still, it seems to me that what rules out epistemic interpretations of psi have to do with their interpretation of how properties need to work in some general way, not just what are the properties of quantum mechanics as a theory. The state psi, and how it responds to measurements, are the properties of quantum mechanics, so if one is only asking what these properties imply, then all they imply are the predictions of the theory and nothing else. In other words, the pure mathematics connects only to the actual predictions-- everything else is plain English.

 

[my_wan]

I agree, that's why I never said to drop (2) in favor of (3). I think instrumentalism goes too far, it strips science of too much of its meaning just to have the benefit of being completely concrete. I would say that (1) is what every scientist in effect does in their daily progress but cannot justify as anything but convenience, and (3) is the only thing any scientist can really justify as actually true, but (2) is the compromise that gets something of the best of both worlds without being internally inconsistent.
I'm saying we should frame science as just what science is, and stop pretending it is something else. In particular, we should stop pretending that because theories invoke properties to great advantage, this means that the ontology that properties invoke is anything but a pretend ontology that we use as a convenience for doing science. The connection to a real ontology, if any such thing even exists, is both vague, and unnecessary to specify, to do science, so why not just accept this truth? When one does accept this truth, the idea that a property could determine the outcome of an experiment is dubious. A property of a theory can determine the prediction of a theory, but the PBR theorem is not about how to use QM to make a prediction, it is about what kinds of backstories we can tell about quantum mechanics that will be consistent with whatever brand of realism we are trying to make consistent with quantum mechanics.

Again, we are not so far apart in a pragmatic sense. Yet our perspectives on the attitudes of what scientist actually do appears to be at odds. Perhaps because I'm a bit older than you and the present set of attitudes have only really gotten embedded in the last 25 years or so. So perhaps a bit of recent history of attitudes is in order.

When Feynman first presented his now famous Feynman diagrams they were rejected outright by the most prominent of the then present established peers as plain silly. Why? Because they accused him of trying to visualize what was "really" going on. The scientist since the famous Einstein debates had deeply embedded the idea the notion that "pretend ontology" was ALL any ontological construct was. Hence anything that even smelled like a picture, rather than pure mathematics, was silly. Scientist generally took the extreme end of the very position you are advocating and even accusing them of taking the opposing view.

Now with Feynman's obvious success this opened up some gates. The stream of views leaving out of those gates has gained momentum ever since, and this hasn't been all good or all bad, but has lead to a lot of good research on questions that certainly does need asked. When the various flavors of quantum interpretations were posited, such as Schrodinger's cat they weren't meant as interpretations of what was really going on, they were merely meant as conceptual devices to articulate the differences in QM and classical physics. As these questions resurfaced following Feynman the so called Gurus began to appear. Yet the gates weren't really opened up till Bell started publishing on Bell's inequalities.

In the words of GianCarlo Ghirard:

Actually I remember well that, at the beginning of the sixties when I started my scientific carreer, to work on foundational issues was considered by a great part of the scientific community a loss of time, a choice to pay more attention to (irrelevant) philosophical issues than to precise scientific problems. Luckily enough, the sixties were also the years in which another deep thinker, John S Bell, by deriving the celebrated inequality that bears his name [1], has given a tremendous imput to our understanding of reality by making clear that nonlocal features characterize most natural processes.

Today even what Christopher Fuchs might call the Copenhagenist wouldn't even be recognized by the authors of the Copenhagen Interpretation (CI). The very notion that CI, as originally stated, entails a collapse of the wavefunction is absurd. It disavowed any real notion of a wavefuction to make any notion of a collapse at all meaningful. Bell's inequality and the Aspect experiment drew in a public attention which often had their own SyFy (Imagine it Stupider) perception of the situation. The media doesn't give a crap what scientist think but are all too willing to characterize their BS as "what scientist say".

Then there is of course the priest of the religions Christopher Fuchs spoke of, which are trying to sell their interpretations by pointing to what they claim is "real" (their God) when nobody is looking in the interpretation. All hogwash as far as science is concerned. If they can offer some real science instead of BS interpretations explicitly designed to avoid predictions maybe they could be of some value. But that is just too risky for these "priest" of interpretations.

---
Does all this stupidity mean I want things returned to what they were before Bell, the attitude you seem to be advocating? The same attitude that got the Feynman diagrams initially treated as naive mad ravings about actual reality. Absolutely not! Important questions are being explored. To me the whole argument over what science "is" is ever bit as silly as all the "priest" at the conventions claiming if we only believe in their God everything will make sense. That goes for (non)realist poo pooing (non)realist also. It takes the whole array to explore the space of possibilities and only nature has the final word when somebody figures out how to ask the right question(s).

 

[bohm2]

I e-mailed one of the authors for clarification and Matt (Matthew F. Pusey) was very kind to answer and I'm sure he doesn't mind me posting this. I hope not. But since this debate has driven some of us to feel like smashing our computer monitors and unable to study either, here is his response:

My question:

Regarding your recent paper when you write that "this work, however, proceeds on the assumption that quantum systems-like atoms and photons-exist, and have at least some physical properties."

Are you assuming that these physical properties are just "theory-relative" without any presumption that such properties actually correspond to what really exists or are the assumptions based on properties actually being physically real?

Matt's response:

The idea is that the physical properties are "real" in the sense that they are not merely calculation devices in our heads, and can therefore be the cause of measurement outcomes. I suppose it is difficult to talk about physical reality without being "theory-relative" at all - for example the very ideas of photon and electrons come from theory. The result doesn't really depend on your exact philosophical standpoint on the nature of physical reality - we simply show that if a "reality" of some sort exists and satisfies our assumptions then the quantum state is "real" in whatever sense of the word "reality" the assumptions hold.

 

[DevilsAvocado]

I e-mailed one of the authors for clarification and Matt (Matthew F. Pusey) was very kind to answer and I'm sure he doesn't mind me posting this. I hope not. But since this debate has driven some of us to feel like smashing our computer monitors and unable to study either, here is his response:

The idea is that the physical properties are "real" in the sense that they are not merely calculation devices in our heads, and can therefore be the cause of measurement outcomes. I suppose it is difficult to talk about physical reality without being "theory-relative" at all - for example the very ideas of photon and electrons come from theory. The result doesn't really depend on your exact philosophical standpoint on the nature of physical reality - we simply show that if a "reality" of some sort exists and satisfies our assumptions then the quantum state is "real" in whatever sense of the word "reality" the assumptions hold.

[my bolding]

Excellent! I love it! :!)

This is what I have been trying to say since post #152! ()

From my perspective, the discussion what "hidden variables" are, and what properties they might posses, and how they commute these properties, is interesting but maybe 'premature', because I could claim that "hidden variables" are "Little Green Men with Flashlights" representing on/off, |0⟩ or |1⟩, and it would be quite hard to prove me wrong...

Therefore, this is clearly a question on realism. Is there "something" there when no one is watching?

Now, the PBR theorem has clearly a strong connection to the standard Bell framework, and therefore we cannot talk about realism without the other strongly related concept locality (despite Ken G’s 'aversion').

Thanks bohm2!


P.S. And of course, another formulation (philosophical-mumbo-jumbo-bulletproof): Is the moon there when nobody looks?

 

[bohm2]

Not another interpretation!

In a recent paper, Pusey, Barrett and Rudolph claim to proof that statistical interpretations of quantum mechanics do not work. In fact, their proof assumes that all statistical interpretations must be based on hidden variable realism. Effectively, the authors demand from the start that reality must be decided by mathematics, and not by measurements. If this unjustified assumption is dropped, the quantum formalism has a natural statistical interpretation that fully explains the paradox presented by the authors. It is therefore possible to conclude that the paradox actually supports the statistical interpretation, demonstrating once more that quantum mechanics should not be explained by measurement independent realities that are never observed and therefore lie beyond the reach of empirical tests.

The explanations given by Bohr, Heisenberg, von Neumann and many others all assume that (a) quantum mechanics should be interpreted statistically, and (b) hidden variables do not work. Could it be, that the authors of meant this group of physicists, when thay state that “Some physicists claim that quantum systems do not have physical properties, or that the existence of quantum systems at all is a convenient fiction”? This statement is certainly a drastic misrepresentation of the empirical position that objects can only be known by their observable effects. The authors contrast this by professing a belief in the existence of “quantum systems - like atoms and photons.” However, this seems to contradict their own conclusions, since the reality of a quantum state represented by superpositions of atom or photon numbers should be hard to reconcile with the existence of atoms and photons as real objects. Obviously, the authors of [1] are unaware of the difficulties associated with terms like “existence”, otherwise they would not think that the conviction that objects must “exist” in some absolute form could justify their assumption of a measurement independent reality. The positions that collide here are the empirical tradition that assumes that the existence of an object is known by its observable effects (and nothing else) [2], and the idealist or dogmatic [3] position that we know about the existence of an object from an authoritative theory.

Somebody on this forum will love this paper, I think?

The quantum state should be interpreted statistically
http://lanl.arxiv.org/PS_cache/arxiv/pdf/1112/1112.2446v1.pdf

I think these authors are using a similar argument to the "flaw" that Demystifier pointed out in a previous post in this thread?

I believe I have found a flaw in the paper.
In short, they try to show that there is no lambda satisfying certain properties. The problem is that the CRUCIAL property they assume is not even stated as being one of the properties, probably because they thought that property was "obvious". And that "obvious" property is today known as non-contextuality. Indeed, today it is well known that QM is NOT non-contextual. But long time ago, it was not known. A long time ago von Neumann has found a "proof" that hidden variables (i.e., lambda) were impossible, but later it was realized that he tacitly assumed non-contextuality, so today it is known that his theorem only shows that non-contextual hidden variables are impossible. It seems that essentially the same mistake made long time ago by von Neumann is now repeated by those guys here.

 

[Fra]

The idea is that the physical properties are "real" in the sense that they are not merely calculation devices in our heads, and can therefore be the cause of measurement outcomes.

I assume that human heads are just a metaphor for the "memory of an observer" (which generically is a piece of matter).

Then as I tried to advocate before it's perfectly possible that the properties are "only in heads" YET they DO influence the measurement outcomes!

The key is that there is more than one head! And the behaviour of physical system can essentially be seen as "interacting heads". And here it really is not a far stretch that the EXPECTATIONS of the heads, really does determined the interactions if the action of any head is assume to follow a rational action upon it's own expectations. There you go, it's group dynamics of expectations.

The best analogy is the theory of expectations and rational actions in economical dynamics. So as a first step, one might have a hard time to grasp that expectations rules physical interactions, but the concept is easier to understand in economy. Try to predict the stock market for example.

My opinon is that expectations are "real" as oppose to just living in a mathematical realm, but not real in the sense of observer invariant or detached from empirism. I see it more as "real empirical records" but these records are observer dependent, and other observer can only establish some of kind "reality" of other observers records by implicitly noting that they influence(but not fully determine) their actions.

/Fredrik

 

[my_wan]

Fredrik makes a good point. People talk about what we imagine as if there is nothing in our head that determines what we imagine. Sociologist have a term for "group dynamics of expectations", it's called "http://www.enotes.com/oxsoc-encyclopedia/definition-situation". Even if you could predict the stock market, once you buy stock as a result of that prediction you change the stock market so the prediction is no longer valid. The more stock you buy the more you change what the stock market does. Here buying stock is a lot like making a measurement. In QM you can only find the price of a stock by purchasing the stock (perform a measurement).

The information centric approach of Fredrik appears perfectly valid to me, in spite of my own predispositions toward realism. I don't think the two are mutually exclusive. In some ways an information centric approach is superior, due to the unpredictability created through feedback like in the stock market analogy, but neither would it erase certain advantages of an empirically valid observer independent model. Especially with respect to defining general causal constraints on the system.

 

[Fredrik]

Effectively, the authors demand from the start that reality must be decided by mathematics, and not by measurements. If this unjustified assumption is dropped, the quantum formalism has a natural statistical interpretation that fully explains the paradox presented by the authors.

To be more specific, the authors (PBR) define the statistical interpretation of a quantum theory as "there's a ψ-epistemic ontological model for it", and if we ignore the possibility that there might be such a thing as an ontological model, and instead consider a way of looking at QM that involves negative probabilities, then we're not going to find a contradiction in the calculation that PBR did.

This guy is essentially just saying that if we don't make any of the assumptions that PBR did, then we also don't arrive at their conclusions. And then he let's us know that he knows a cool trick with negative probabilities. I find it hard to believe that this article will be published anywhere.

I think we started this discussion too soon. We still don't even know if the PBR article will be accepted for publication (I would at least demand massive rewrites if I was the reviewer), and I think comments about it will continue to appear, many of which will be garbage. I don't think I will bother to read anything else about this until someone has published a rigorous version of the mathematical argument.

 

[my_wan]

To be more specific, the authors (PBR) define the statistical interpretation of a quantum theory as "there's a ψ-epistemic ontological model for it", and if we ignore the possibility that there might be such a thing as an ontological model, and instead consider a way of looking at QM that involves negative probabilities, then we're not going to find a contradiction in the calculation that PBR did.

Funny thing is I still have no freaking clue what set of possible models ψ-epistemic ontological entail. Nor did the paper use any term or morph of those terms anywhere in the document. Nor does the notion that they somehow screwed up their own description but somehow you pieced it back together from a referenced articled that shared absolutely no common terminology.

So when you say "specifically" I'm still left with the vague notion that specifically you mean some "sort of electromagnetic phenomena". Sounds just as specific to me.

Now look at Matt's email response:

The result doesn't really depend on your exact philosophical standpoint on the nature of physical reality[...]

And he's absolutely right. It doesn't depend on your notion of ψ-epistemic or ψ-epistemic ontological either, which you offer no clues to the meaning outside the labels you placed in this singular context with no clarification on even that one context.

The authors did perfectly well and sensible with their own words. Figure out why their own words were perfectly sensible in the context they provided, even if the terminological was not unique to that context they explicitly provided. Else if you are going to throw their own word away as hogwash don't pretend you somehow can intuit what they meant from a reference paper using no common terminology, or variant thereof, whatsoever. Or explain the FULL context of how you intend the meaning of such terminology.

 

[Fra]

but neither would it erase certain advantages of an empirically valid observer independent model. Especially with respect to defining general causal constraints on the system.

Perhaps we can agree, if I get you right, "certain advantages" are indeed compatible, or even an integral part of my view:

Each observer, IMHO, has an empirically justified view of an "effective reality", and this contains the best match to observer invariants - to the extent that observer has inferred. And indeed, the concept of rational action means that THIS is definitely working as a constraint on the observer actions; in the sense that it's EXPECTATIONS of "invariants" with respect to OTHER observers, helps this observer to make place his bets - this is IMO the "certain advantage".

Interpreting in this way, I can agree on your last point as well. What I think is important though, is that we do not confuse OUR (or say MY OWN) view of "effective reality with invariants" with the concept that ANY observer (read any piece of matter) has it's potential OWN subjective view of another "effective reality".

The mind trap as I see it, that is easy to fall into, is the mental picture that there exists in some absolute timeless sense some "real reality" that connects all the "effective realities" by some master symmetry. One might first thinkg that "what's the difference" between effective reality and real reality? From the empirical point within the view of a GIVEN observer, there is no difference since the whole point is that there is no way to distinguish them!

But the real issue is when one expects the two "effective realities" of two INTERACTING observer to be the same. This is IMO an unjustified expectation that only makes sens in some mathematical realm, and insisting on it tend to result in other pathologies that I think are related to this simply becaue in mathematical realm there are no selection principles except inconsistencies. For example certain landscape problems or hard initial value and finetuning problems.

Still there is no denial that the "effective reality" is an essential to any given observe, and this of course INCLUDES *expectations* on how this observers observations relates to fellow observers etc. One can imagine semi-equilibriums, where a group of observers can actuall agree on observer invariants. But this presumes the group has equilibrated.

/Fredrik

 

[Fredrik]

Funny thing is...

Your refusal to accept that the PBR argument is an attempt to rule out what HS calls ψ-epistemic ontological models is quite bizarre. I have explained it lots of times, so I'm not going to do it again.

I have no idea why you think that the Pusey quote somehow means that I'm wrong about something.

 

[DevilsAvocado]

I assume that human heads are just a metaphor for the "memory of an observer" (which generically is a piece of matter).

Then as I tried to advocate before it's perfectly possible that the properties are "only in heads" YET they DO influence the measurement outcomes!

The key is that there is more than one head! And the behaviour of physical system can essentially be seen as "interacting heads". And here it really is not a far stretch that the EXPECTATIONS of the heads, really does determined the interactions if the action of any head is assume to follow a rational action upon it's own expectations. There you go, it's group dynamics of expectations.

The best analogy is the theory of expectations and rational actions in economical dynamics. So as a first step, one might have a hard time to grasp that expectations rules physical interactions, but the concept is easier to understand in economy. Try to predict the stock market for example.

My opinon is that expectations are "real" as oppose to just living in a mathematical realm, but not real in the sense of observer invariant or detached from empirism. I see it more as "real empirical records" but these records are observer dependent, and other observer can only establish some of kind "reality" of other observers records by implicitly noting that they influence(but not fully determine) their actions.

/Fredrik

Thanks Fredrik, interesting.

First let me say that I take yours and my_wan’s argumentation and 'search for knowledge' 100% serious, because to me you seem 100% sincere. Not like "the other guy", who build his own "personal reality" without any rules; creating whatever fits the personal divine worldview – a form of "semi-creationism".

Please forgive me if I’ve misunderstood your model, but afaict, you are saying that "our heads" are the only thing that matters, right? A group of scientists could/should be seen as "interacting heads"; examining the "reality", creating "the theory", setting up "the experiment", and finally examine "the data", correct?

This far, I think have no problem following the logic, but then I’m kinda lost... are you saying that the expectations (all the way from 'theory-making') is what finally decides the empirical data?? Then I must be missing something substantial, because afaict that would require some form of new "magical interaction" between thought/mind/consciousness and matter...?

Or did I get everything wrong from start...

Let’s skip my (hopefully temporal) ignorance and continue with your "EXPECTATIONS of the heads" model. This can only mean that we must trust "our heads" 100%; to always get everything right, and never hesitate, and always trust our senses 100% (carrying 'the information' to "our heads") – because if we cannot, we will get a chaotic and contradictory universe where the "laws of nature" breaks down.

Then the natural question arises:

– Can we do this? Are we "Gods" that get everything right all the time??​

To me, the answer is without doubt, No.

For example, take this simple illusion:

Stare at the center cross for at least 30 seconds to experience
the three phenomena of the illusion

When you stare at the cross for about 30 seconds or so, you will see three different things, in this sequence:

1. A gap running around the circle of lilac discs.
   
2. A green disc running around the circle of lilac discs in place of the gap.
   
3. The green disc running around on the grey background, with the lilac discs having disappeared in sequence.

If you do it 'right', you will see/"measure" three different and contradicting "data" from only "one reality". This will cause problems in "your model"... I think...

But I’m probably missing something... because this 'refutation' seems a little too simple...


Finally, I’ve seen users complaining about a badly souring atmosphere, so let’s lighten things up!

"If I am reading this graph correctly — I'd be very surprised!" -- Stephen Colbert

"You can always count on the Americans to do the right thing — after they have tried everything else." -- Winston Churchill​

P.S. Economics is not a branch of natural science, is it? More like psychology, right? The Nobel Prize in Economics is established by Sweden's central bank, not Alfred Nobel.

 

[DevilsAvocado]

... The mind trap as I see it, that is easy to fall into, is the mental picture that there exists in some absolute timeless sense some "real reality" that connects all the "effective realities" by some master symmetry. One might first thinkg that "what's the difference" between effective reality and real reality? From the empirical point within the view of a GIVEN observer, there is no difference since the whole point is that there is no way to distinguish them!

/Fredrik

I know that SR/GR, Evolutionary cosmology ΛCDM, Evolutionary biology, and Quantum Mechanics at the moment are in different parts of the "scientific universe", but how could ever hope to explain the evolution of Homo sapiens from Amœbas? You would need some form of "real reality" there... unless you are going to refer to "interacting amœbas"...? ()

And you still run into problems with the cosmological evolution...

 

[bohm2]

Now look at Matt's email response:

And he's absolutely right. It doesn't depend on your notion of ψ-epistemic or ψ-epistemic ontological either, which you offer no clues to the meaning outside the labels you placed in this singular context with no clarification on even that one context.The authors did perfectly well and sensible with their own words.

For some reason I have a feeling that you are right. It's just most of us including the authors of the most recent critical piece are just too dumb to figure it out. That kind of makes me feel better.

 

[Fredrik]

Not like "the other guy", who build his own "personal reality" without any rules; creating whatever fits the personal divine worldview – a form of "semi-creationism".

I have to say that your continued attacks on Ken G are kind of annoying. It's not the fact that you keep mentioning that you think he's wrong about something. It's the fact that you keep misrepresenting what he's been saying. I'm not interested enough to go look for evidence for this (other than the fact that I remember that I have several times thought it was obvious that you had misunderstood him), but it seems to me that you have many times claimed that he has views that he simply doesn't have. I thought about reporting you, but I decided that I don't want to force any moderator to read this thread.

If I was him, I would find it very offensive. I know how much it annoys me when people repeatedly claim that I believe something crazy just so they can attack some bizarre statement that I've never made and claim to have proved me wrong. This type of behavior is worse than direct insults in my opinion.

 

[Fra]

A group of scientists could/should be seen as "interacting heads"; examining the "reality", creating "the theory", setting up "the experiment", and finally examine "the data", correct?

Yes. (Except the case where head=piece of matter is more interesting)

This far, I think have no problem following the logic, but then I’m kinda lost... are you saying that the expectations (all the way from 'theory-making') is what finally decides the empirical data??

No, that's overstating it and missing the point.

One thing I've learned from PF about this is that it's extremely hard to convey this. Partly this is because this is more like a research program I describe, and the testable results are still not there to judge.

I'll try to explain more later. But the picture I describe is an evolution, in which the expectations of the future, actually influences the future. But I make an important distinction between determined (exactly) and influence. I think more of the expectations as defining the odds, but the cards are still played at random (but guided by the odds).

This means that my take on the laws of physics, is to understand them as equilibrium agreements in a larger generally open game.

This crazy game of "interacting expectations" can actually EXPLAIN certain equilibrium states that are observer in nature.

Again, the analogy I'm pulling here is NOT quite right (so don't overinterpret) but I think it's still a good hint in the right direction to understand my point.

In economy there is the concept of Nash equilibrium:
"If each player has chosen a strategy and no player can benefit by changing his or her strategy while the other players keep theirs unchanged, then the current set of strategy choices and the corresponding payoffs constitute a Nash equilibrium."
-- http://en.wikipedia.org/wiki/Nash_equilibrium (which btw is 1994 nobel winner in economy)

But here, replace "players" with "matter", and the "set of strategy choices" with the "naked" ( non-renormalized) physical actions of matter then the nash equilbrium corresponds to a situation where matter-matter interactions has reached a steady state and where stabel "observer-invariants" can be defined.

Now the idea behind all this, is to understand and predict WHICH observer invariants (symmetries) we have in nature, how the are related, and how they evolve.

My most remote by bold vision is this: To understand the standard model, as well as it's unification with gravity in terms of rational actions of matter onto other matter (the environment).

Another idea is that once you scale complexity down, there are not a lot of choices at all; and if you consider interacting systems of similar construction, predictions (in line with nash type guidelines) of WHICH stable symmetries that are expected once complexity is increased (=lowering the energy -> low energy limit) should be possible.

Ie. the standard model, is to be understood as an "equilibrium point" in an EVOLUTIONARY context. This should include many of the parameters. I'm crazy enough to think this is possible.

/Fredrik

 

[bohm2]

I have to say that your continued attacks on Ken G are kind of annoying...If I was him, I would find it very offensive. I know how much it annoys me when people repeatedly claim that I believe something crazy just so they can attack some bizarre statement that I've never made and claim to have proved me wrong. This type of behavior is worse than direct insults in my opinion.

I agree. I actually learn a lot from Ken G's posts even though I only recently started reading them. His position also seems pretty consistent and not that controversial among many scientists/philosophers. I'm just wondering if his arguments against PBR are similar to the ones advocated by the most recent article. If I recall he gave a somewhat similar criticism, I think?

 

[DevilsAvocado]

I have to say that your continued attacks on Ken G are kind of annoying. It's not the fact that you keep mentioning that you think he's wrong about something. It's the fact that you keep misrepresenting what he's been saying. I'm not interested enough to go look for evidence for this (other than the fact that I remember that I have several times thought it was obvious that you had misunderstood him), but it seems to me that you have many times claimed that he has views that he simply doesn't have. I thought about reporting you, but I decided that I don't want to force any moderator to read this thread.

If I was him, I would find it very offensive. I know how much it annoys me when people repeatedly claim that I believe something crazy just so they can attack some bizarre statement that I've never made and claim to have proved me wrong. This type of behavior is worse than direct insults in my opinion.

Go ahead, my friend, report me.

Then we could perhaps finally get an official name of the theory/interpretation/philosophy, or whatever, that have occupied almost 400+ posts in this thread. As a SA you are of course aware that personal theories/interpretations/philosophies are not allowed on PF.

"Not interested enough to go look for evidence", well, I can’t see how that makes your attack any different from what you think I’ve have done. You’re just guessing that I have no evidence at all.

I have evidence.

So please be my guest and push that button. If I get 'convicted', I have absolutely nothing to lose, since I’m not interested in spending time in a forum that support this kind of ideas, which according to the rules should not be supported.

Take care and good luck!

 

[DevilsAvocado]

Yes. (Except the case where head=piece of matter is more interesting)

No, that's overstating it and missing the point.

One thing I've learned from PF about this is that it's extremely hard to convey this. Partly this is because this is more like a research program I describe, and the testable results are still not there to judge.

I'll try to explain more later. But the picture I describe is an evolution, in which the expectations of the future, actually influences the future. But I make an important distinction between determined (exactly) and influence. I think more of the expectations as defining the odds, but the cards are still played at random (but guided by the odds).

This means that my take on the laws of physics, is to understand them as equilibrium agreements in a larger generally open game.

This crazy game of "interacting expectations" can actually EXPLAIN certain equilibrium states that are observer in nature.

Again, the analogy I'm pulling here is NOT quite right (so don't overinterpret) but I think it's still a good hint in the right direction to understand my point.

In economy there is the concept of Nash equilibrium:
"If each player has chosen a strategy and no player can benefit by changing his or her strategy while the other players keep theirs unchanged, then the current set of strategy choices and the corresponding payoffs constitute a Nash equilibrium."
-- http://en.wikipedia.org/wiki/Nash_equilibrium (which btw is 1994 nobel winner in economy)

But here, replace "players" with "matter", and the "set of strategy choices" with the "naked" ( non-renormalized) physical actions of matter then the nash equilbrium corresponds to a situation where matter-matter interactions has reached a steady state and where stabel "observer-invariants" can be defined.

Now the idea behind all this, is to understand and predict WHICH observer invariants (symmetries) we have in nature, how the are related, and how they evolve.

My most remote by bold vision is this: To understand the standard model, as well as it's unification with gravity in terms of rational actions of matter onto other matter (the environment).

Another idea is that once you scale complexity down, there are not a lot of choices at all; and if you consider interacting systems of similar construction, predictions (in line with nash type guidelines) of WHICH stable symmetries that are expected once complexity is increased (=lowering the energy -> low energy limit) should be possible.

Ie. the standard model, is to be understood as an "equilibrium point" in an EVOLUTIONARY context. This should include many of the parameters. I'm crazy enough to think this is possible.

/Fredrik

Thanks Fredrik, I don’t think it’s crazy at all, and the mere fact that you acknowledge that you are looking for a solution, instead of pretending to be the beholder of the TRUTH and the official spokesman of Niels Bohr, makes your ideas much more worth listen too.

I’ll get back when I’ve understood more (unless I’m not banned by then ).

 

[Fredrik]

As a SA you are of course aware that personal theories/interpretations/philosophies are not allowed on PF.

The best example I've seen of an overly speculative personal theory in this thread is your post #380. I haven't read all of Ken G's statements, but the ones I've read haven't been personal speculation. He's been talking about how words are defined, and how he thinks words should be defined, etc., and you can argue that some of it doesn't belong in this thread (I would agree), but I haven't seen any personal theories.

"Not interested enough to go look for evidence", well, I can’t see how that makes your attack any different from what you think I’ve have done. You’re just guessing that I have no evidence at all.

Do you always mischaracterize what you're replying to? I'm not guessing. I told you that I distinctly remember that my reaction to several of your posts was that you had clearly misunderstood Ken. When I said that I'm not going to look for evidence, that only means that I'm not willing to spend two hours finding the relevant posts in a 29-page thread, highlighting the relevant parts, etc. You can consider it just an opinion if you want to, but it's not a guess.

Edit: Here I misunderstood what you said. I'm sorry about that. I thought you were saying that I was just guessing that you had misunderstood some of his statements, but you were saying that I'm guessing that you don't have evidence to back up your claims. I concede the point that I don't know if you have any evidence against him, and I obviously retract my suggestion that what you said in the quote above was a mischaracterization of what I said. That was a misunderstanding on my part.

I’m not interested in spending time in a forum that support this kind of ideas, which according to the rules should not be supported.

What ideas are you talking about?

Don't you think that leaving the forum because a few people disagree with you, about whether your personal attacks on Ken G are appropriate, would be a pretty bizarre overreaction?

 

[mattt]

All Ken G is trying to say (in my opinion) is that we should not mistake our models with whatever our models are trying to model.

And I suppose everybody agrees with him on that.

 

[apeiron]

Then we could perhaps finally get an official name of the theory/interpretation/philosophy, or whatever, that have occupied almost 400+ posts in this thread. As a SA you are of course aware that personal theories/interpretations/philosophies are not allowed on PF.

The baffling thing is that your misconceptions were corrected many pages ago...

https://www.physicsforums.com/showpost.php?p=3642301&postcount=271

Idealism is quite different from what I'm advocating, I'm actually advocating something more along the lines of "scientifically consistent realism." The difference between idealism and realism is simple-- idealism asserts that reality is fundamentally mind-constructed, so there is no reality outside the mind. This would also require I speak of my mind, because if there is no reality outside my mind, then your mind does not exist outside of my mind. I've never said any such thing, just look.

Indeed, scientists often find it useful to adopt realism, and I am no exception. Realism asserts that there is a reality outside our minds, and our minds are trying to figure it out. This is the stance I take. But here we must distinguish two brands of realism, which I would call "naive realism" (the idea that when we conceptualize reality, we hit it spot on, in complete contradiction with both the obvious limitations of our senses and our intelligence, and ignoring the clear evidence to the contrary from the history of our own physics), versus what I would call "scientifically consistent realism" (a realism that does not disregard that evidence).

This seems to be utterly straight-forward and uncontroversial. So examine these words again and make it clear what your quarrel is about.

 

[bohm2]

This was KenG's criticism of PBR in this quote from a previous post:

What is incorrect here? Well, it certainly isn't "technically" true, because it leaves out a very important step in the logic. Hsu, and many others it would seem, have tacitly, and without even realizing, assumed this huge leap of faith:

(ia) the existence of an "underlying reality" requires that what happens in that reality be determined by the parameters in some theory!

And that last PBR critical paper appears to argue this same point:

The positions that collide here are the empirical tradition that assumes that the existence of an object is known by its observable effects (and nothing else), and the idealist or dogmatic position that we know about the existence of an object from an authoritative theory.

http://lanl.arxiv.org/PS_cache/arxiv/pdf/1112/1112.2446v1.pdf

But is that what the authors of PBR are claiming? Consider again Matt's response:

The idea is that the physical properties are "real" in the sense that they are not merely calculation devices in our heads, and can therefore be the cause of measurement outcomes. I suppose it is difficult to talk about physical reality without being "theory-relative" at all - for example the very ideas of photon and electrons come from theory. The result doesn't really depend on your exact philosophical standpoint on the nature of physical reality - we simply show that if a "reality" of some sort exists and satisfies our assumptions then the quantum state is "real" in whatever sense of the word "reality" the assumptions hold.

 

[qsa]

The baffling thing is that your misconceptions were corrected many pages ago...

https://www.physicsforums.com/showpost.php?p=3642301&postcount=271





This seems to be utterly straight-forward and uncontroversial. So examine these words again and make it clear what your quarrel is about.

while I understand the sentiment, but I beg to differ. You are saying in effect that our mind and all the instruments we can muster could be blind to some aspects of nature. But there is no proof of that. If anything, our intelligence and the history of science has shown that we are doing damn good if history to be taken as evidence.

Our models have been getting better and better representing reality , so who is anybody to stop that progress. We are at the edge of the deepest secrets of reality, we are producing Quantum Gravity theories and spitting them out like candies, and people say we cannot really know reality! If anything, it is clear that reality is astonishingly comprehendible.

Even today and it has been for a while , it has been conjectured that reality could be just a mathematical structure , in that case there is a window that we can have an isomorphic structure to reality. who is to stop that possibility.

I think we should totally ignore the mind thing (and be very suspicious of it), it is unconstructive. We should be bold and go where no man has gone before.