> As a strawman, it is not an entirely inadequate proxy for what I actually said, but it is not what I actually said.

It is exactly what you said. That is the exact misconception that was being discussed when you replied, quoting another person, and said “it’s a common misconception among physicists.” I’m always amazed by people on Reddit who pretend they didn’t say the things they said, that are still there for all to see.

> This is r/philosophy, not r/physics.

Yes, in an article about philosophical ideas related to a model of physics. You cannot meaningfully consider the philosophy of physics if you don’t first understand the physics.

> Oops.

Did you fall, or something?

> Quantum mechanics is easily misunderstood. Perhaps owing to the fact it cannot be easily (or actually) understood.

But we aren’t talking about the entirety of quantum mechanics. We are talking about one specific and common misconception of it. And that particular misconception arises primarily because the words “observation” and “measurement” mean something different to a physicist than they do to a lay person.

> So despite the devastation you have wreaked on the strawman argument that I have besmirched the good name of Niels Bohr, the actual issue I am discussing remains, unperturbed.

No, I responded to two specific things you claimed. One, your claim that physicists commonly suffer from the misconception that conscious observation plays a special role in quantum mechanics. Two, that Niels Bohr deliberately confused the two. The first claim is laughably wrong and makes it very clear you have no experience with the actual physics community; and the latter is demonstrably false and demonstrates your propensity to make shit up for some reason that I can’t comprehend.

You keep defending your claims, but whenever I make any reference to those claims you call it a strawman. That just makes you dishonest.

> I don't identify you as a neopostmodernist to "make myself feel better", I do it to accurately describe your position and practices, or at least the intellectual milieu and time period of your reasoning.

You don’t know enough about my positions and practices to call me anything, since the only things I’ve addressed are whether physicists possess a particular misconception, the origin of that misconception, and what words Bohr used. This would be like watching someone walk down the street and diagnosing them with heart disease.

> The problem is that "clarifying [...] the words used to talk about" any subject, let alone the supremely difficult subjects of QM or consciousness, doesn't actually work as well as you insist it should.

But it does. I actually teach these things, I deal with this all the time. In this particular instance, about the very specific and precise thing we’re discussing, it works quite well. In fact, you can see it working in this very Reddit post, among others on the subject. Your imagination — or perhaps your own confusion — notwithstanding.

> Personally, I don't suffer from this problem, because my philosophy resolves the nature of consciousness more completely than neopostmodern philosophies do.

How pretentious of you. This attitude is certainly consistent with your previous assertion that Einstein and Bohr weren’t qualified to talk about quantum mechanics.

> I can understand the parallels between quantum uncertainty and existential uncertainty, and recognize the meaning of those parallels without conflating the subjects.

And yet you’ve demonstrated that you clearly don’t understand the physics (see your claim that this year’s Nobel prize has nothing to do with interpretations of quantum mechanics). So sorry if I doubt your ability to see parallels so crystally clear when you don’t even understand one of them in the first place.

> But the problem remains, even for me, when I attempt to discuss these issues with other people, and the more neopostmodernist they are, the more cantankerous they get.

It’s more likely that people who actually understand the physics get frustrated when you, who clearly don’t, make baseless and false claims about something you don’t understand, and then accuse them of inventing strawmen when they correct your errors. You aren’t arguing honestly. Hell, you’re still defending your claim about Bohr instead of admitting that you took this shitty article’s awful summary of his argument as a stand in for his actual words, and you’re too proud to admit you made a mistake.

> I think it is fair to say this is true in principle, but in real terms you are overstating the case

No, not really. What do you think condensed matter physics is, if not the application of quantum mechanics to macroscopic systems? What I said is both true in principle and proven in reality, even if it’s often too difficult to do.

> We know that classic physics relates to, for instance, the collapse of superpositions and entanglement through decoherence into classically deterministic states, yes, but not really how or why.

That’s fine. Scientific models aren’t concerned with how or why. It’s pretty easy to prove that the mathematical model that we call quantum mechanics reduces to classical mechanics in the appropriate limits of energy and scale based solely on the fundamental principles of quantum mechanics. In fact, mathematically the only distinction between the two arises entirely from the fact that in classical mechanics [x,p] = 0 and in quantum mechanics [x,p] = ihbar.

You’re right that we don’t fully understand the mechanisms by which macroscopic systems lose coherence. But that doesn’t mean we don’t know that, regardless of those details, quantum mechanical behavior necessarily reduces to classical mechanics in appropriate macroscopic limits. We also know that macroscopic systems are represented in our models of quantum mechanics by the same sorts of density matrices as everything else is. Of course, this is all predicated on the assumption that quantum mechanics is an accurate model, which there’s some small chance it isn’t, but this conversation is meaningless outside of that assumption.

> It doesn't really mean we actually can derive classic physics from QM, explicitly, just that we assume it must be possible theoretically.

No, you’re wrong. We cannot derive the stress tensor for a chair when I’m sat on it using quantum mechanics (which we could do using classical mechanics) because it’s simply much too complex a feat. But the neat thing about physics and math is that we can often prove things to be true in general more easily that we can actually do something for a specific, complicated case, but that first proof nonetheless implies that a determined and resourceful enough entity could do the latter, too. This is one such case, where mathematical proofs of the correspondence principle between quantum mechanics and classical mechanics exist. See, for example, the Ehrenfest Theorem. A different alternative is to take the limit as the ratio of hbar to a relevant scale factor (multiple choices could be made here) approaches zero, and then quantum mechanics and classical mechanics become mathematically identical models.

> Your profession of faith in physical realism is scientifically appropriate, but philosophically it is akin to a declaration of omniscience.

My comment has nothing to do with physical realism. My comment is entirely based purely on the mathematical properties of quantum and classical mechanics.

> You're building a strawman here. The nature of the issue is broader than just that one word.

No, I’m not. You keep saying that the misconception that observation requires a conscious observer is a common misconception among physicists. It is not. I don’t know where you’re getting this idea but it’s entirely false.

> The ones I used, which is why I said that. I'll leave it for you to obsess over which ones exactly.

So you’re blaming Bohr for your choice of words? Good on ya, that makes so much sense! /s

> Nah. The prize related to the "shut up and calculate" parts of the science, not their interpretations and conversations.

Then you frankly don’t understand it. I was beginning to gather as much by your other comments, but this is the nail in the coffin. The argument Einstein and Bohr were having was about whether the universe can be locally real (another example of scientific/philosophical terminology being easy to confuse). The argument they participated in led to the creation of different possible interpretations of quantum mechanics and culminated in John Bell realizing that any locally real interpretation must predict different correlations than an interpretation that isn’t locally real. He was hoping and expecting that this would allow physicists to show that the universe is in fact locally real, making quantum mechanics a bit easier for many to swallow. This Nobel Prize was awarded to the primary experimenters who tested those correlations, and who found the opposite of what Bell hoped. Bell’s theorem and tests of it are absolutely central to any discussion about interpretations of quantum mechanics, and they’ve ruled out all interpretations consistent with Einstein’s argument. The notion that Bell tests are unrelated to interpretations of quantum mechanics is laughably wrong.

> LOL. Yes, you misunderstand the problem. You are what I refer to as a neopostmodernist. If only something as simple as Bell's Theorem could be used to sort out language, consciousness, and existential truth.

You are what I would refer to as obtuse. You’re just changing what we’re arguing about halfway through to make yourself sound smarter. I am not arguing about the details of language, consciousness, and existential truth. I am merely pointing out that the language used to describe quantum mechanics is easily misunderstood, and that the specific misconception that quantum mechanics places conscious observation on a pedestal is easily dispelled by clarifying what the words used to talk about quantum mechanics means. But go ahead and call me a “neopostmodernist” if using big made up words makes you feel better, and accusing me of misunderstanding grandiose problems that were never under discussion in the first place.

Please point to the part of that article that you think supports your claim. Yes, it provides a description of the physical properties of nature at the scale of atoms and subatomic particles, and those things make up macroscopic systems. You can recover all of Newtonian mechanics from quantum mechanics.

The properties of a rock are determined by the properties of the things that makes up the rock, and how they interact with each other, and all of those are quantum mechanical. Macroscopic systems can absolutely demonstrate quantum mechanical behavior. I even gave you an explicit example already. A macroscopic system would be represented in quantum mechanics by a very high dimensional density matrix, but a density matrix nonetheless, no different in principle from the density matrix representing a pair of entangled electrons.

Then that doesn’t make any sense… Macroscopic phenomena are explained and underpinned by quantum mechanics. Whatever metaphysics surrounds quantum mechanics also necessarily applies to macroscopic phenomena. That it’s not usually noticeable is another matter.

> Unfortunately, outside of that restricted activity, physicists are as apt as any other person to expound upon what they believe are the implications of their physics.

As someone who has spent decades in physics academia, I’ve never met someone at or past the graduate school level who would make the mistake of thinking that “observation” in quantum mechanics implies observation by a conscious observer, unless explictly talking about some sort of consciousness-causes-collapse interpretation. I’m not arguing that physicists can’t make mistakes or harbor some misconceptions, but negligibly few will make the mistake you’re claiming.

> It was a poor choice of words on my part.

What was a poor choice of words? Which words, exactly, are you referring to? The article doesn’t use any of his words. It summarizes what he says. If you want to read his actual words, here’s an example from a discussion he has with Heisenberg about objectivity and subjectivity. Here’s a particularly relevant excerpt:

> And what predictions we base on such findings depend on the way we pose our experimental question, and here the observer has freedom of choice. Naturally, it still makes no difference whether the observer is a man, an animal, or a piece of apparatus, but it is no longer possible to make predictions without reference to the observer or the means of observation.

I’m not sure how that could be confused, unless you cherry pick bits and pieces of his words so as to make them misleading.

> The truth is the distinction itself is not so simple a matter, nor something physicists are qualified to assess to begin with.

The details of the distinction aren’t simple, but the distinction between conscious observer and not is fairly straightforward, and the topic of conversation here. Also the claim that this is something that physicists aren’t qualified to assess, let alone discuss, is absurd. It certainly requires some philosophical chops, but it also requires a detailed technical understanding of fundamental physics, which very, very few philosophers have.

> Bohr assumed there is a [meta]physical truth that his work explored, as did Einstein; they were simply discussing what that truth was, which of their conflicting explanations was more accurate. Which means they were both failing to "shut up and calculate",

They were physicists exploring the implications and consequences of a new physical model. They were doing science, and their thought experiments and arguments led to further understanding that eventually underpinned physical, metaphysical and philosophical analysis of the matter. If they had those discussions 40 years later they’d have been pissing into the wind. But they didn’t, and their discussions led to the EPR paradox, the idea of hidden variables, Bell’s theorem, etc. This year’s Nobel prize has its roots in the very conversations you’re claiming these physicists — the foremost experts of the subject at the time — weren’t qualified to have. Talk about pretentious…

> I don't believe that is the case. The misconception arises often because of the nature of consciousness and quantum weirdness, and the potential for killing two birds with one stone, which most people find very tempting.

As someone who teaches this, I can assure you you’re wrong. It is difficult to talk about superposition and complementarity in a clear and concise way, because the technical language is confusing because it uses words that people have preconceptions about. You can either be clear, or you can be concise, but very rarely both. And worse, once a misconception always a misconception: it propagates. You can see it here on Reddit all the time. Someone who doesn’t understand states it with confidence, or someone who understands tries to explain it concisely and people misunderstand, and then they spread it to others.

This misconception is very easy to dispel simply by having a careful talk about the meaning of words, and that tells me it’s the words that are the main problem.

I’m not sure what you mean by that. What is “it”?

That’s not true at all. Quantum mechanics describes macro structures through its descriptions of the things that make up those macro structures. It’s just impractical to use quantum mechanics to describe the macroscopic world, because classical physics is easier and in the vast majority of circumstances more than good enough.

In fact, we have constructed macroscopic quantum systems (like the mirrors used in LIGO, for example). There are also many macroscopic phenomena that we only understand through quantum mechanics, like why metals tend to be reflective or lustrous.

You’re talking about solipsism. It cannot be disproved, even in principle. However, it is typically presumed implicitly false in any conversation about reality, because otherwise there’s no point in the discussion.

Oh, that’s what you meant. It’s true that we can’t measure the one-way speed of light, but we do know that the two-way speed is 300 million m/s and isotropic, and that is always what is meant by “the speed of light” unless explicitly stated otherwise. If this is actually what the person was referring to, then they were being absurdly obtuse.

> Unfortunately, it is also a common misperception among both physicists and philosophers, as well.

Among philosophers, yes. Among people who studied physics in college? Sometimes. Among actual practicing physicists? No. Not often enough to matter.

> In fact, there may well be good reason to believe that Bohr himself was willfully, perhaps even intentionally, confusing the issue to begin with.

No, we have plenty of Bohr’s research, correspondence, and seminars to know that Bohr did indeed understand the distinction, and did not deliberately try to confuse the issue. There is zero reason whatsoever to believe what you’re suggesting. The article isn’t quoting Bohr, it’s poor use of words doesn’t reflect Bohr’s meaning. This misconception arises so often because physicists appropriated colloquial words for technical meaning, so people without training or expertise read/hear things and don’t realize that they’ve misunderstood, because they don’t realize the words don’t mean what they think they mean.

I do agree that the article is sensationalist, though, since its attempts to describe the concept of local realism to an inexpert audience are ignorant or incompetent, depending on whether the author actually understands it themself.

That’s not a “fact.” The speed of light is frame invariant, so it’s one of the few things that’s not relative in the first place.