Quantum mechanics being "impossible to understand" is just cope to preserve a dominant ideology
(Audio version of this post for those who can't be bothered to read it all.)
If you watch any pop-sci YouTube channel, you have probably heard the old story: physicists used to believe in this silly thing called the aether, but then the Michelson-Morley experiment disproved it in 1887, and Einstein replaced it with his theory of special relativity in 1905, which is "the most tested theory of all time."
But this is historical revisionism and does not accurately reflect the reality of what actually happened.
The 1887 experiment was only intended to test aether models where the aether is directly detectable. Its negative result could imply the aether doesn't exist, or it could imply it is only indirectly detectable.
Indeed, in 1904, the physicist Hendrik Lorentz put forward an aether model whereby the aether is not directly detectable, and thus was consistent with the Michelson-Morley result.
This model is mathematically equivalent to special relativity, and in fact Einstein's 1905 paper was explicitly in response to Lorentz's paper.
Since they are mathematically equivalent, the claim that "special relativity is the most tested theory of all time" makes no sense because no experiment can directly distinguish between Lorentz's 1904 model and Einstein's 1905. If you were to experimentally confirm time dilation, for example, well, both Lorentz's and Einstein's models predict that, so you didn't distinguish them.
Einstein's theory thus won out on philosophical grounds, not empirical grounds. Einstein had, at the time, the stronger philosophical argument: if the aether is not directly detectable, then maybe it doesn't exist, so maybe we should try constructing a model which makes the same empirical predictions as Lorentz's theory but without the aether.
And that is precisely what Einstein's 1905 paper achieves. This convinced basically every physicist to abandon Lorentz's ideas and adopt Einstein's ideas.
So, if Einstein's 1905 paper showed that the undetectable aether is not necessary to make the right predictions, what's the issue? Why do I even bring it up? Seems like all of this is completely reasonable.
I bring it up because of a caveat Einstein was well aware of himself: Lorentz's theory only renders the aether directly undetectable. It does offer a path under which its existence can be indirectly verified, and this bothered Einstein significantly, since he knew it would rule out his special relativity.
What is this indirect verification? The existence of Lorentz's aether can be indirectly verified if we can provide any experimental evidence, at all, that nature contains, anywhere, in any empirical observation, non-local effects.
Why?
Well, if two events occur so far apart and in such quick succession that not even light can traverse the gap, then special relativity predicts that different observers can disagree as to the temporal ordering of the events, measured on their clocks.
If no effect can travel faster than light, then these disagreements about the temporal ordering of events are always causally disconnected, and so it has no real implications.
If an effect can travel faster than light, then the causal sequence can become out-of-order in some perspectives, leading to causal paradoxes and logical inconsistencies in the theory.
This is only true for special relativity, however, because Einstein's theory treats the time-readings on clocks as equivalent to true, ontological time. Lorentz's theory treats the time-readings on clocks as an emergent feature and not fundamental, and so it is perfectly consistent for two observers to disagree about what event happened first without there being a paradox, because one of them can just be wrong and the other correct.
Why is all this relevant?
Newton's theory of gravity is unambiguously a non-local action-at-a-distance theory. Einstein knew that if he wanted his theory of special relativity to make sense, he needed to replace Newton's theory with a local theory of gravity, and so he did precisely that: developing the theory of general relativity.
However, Einstein also realized quantum mechanics is a non-local theory, and tried for the rest of his career to replace it with a local field theory, but never succeeded.
In fact, in 1964, the physicist John Bell proved it is impossible to replace it with a local theory without contradicting its empirical predictions. As Bell concludes at the end of his 1964 paper, either quantum mechanics is wrong, or the states of particles cannot be Lorentz invariant.
If they cannot be Lorentz invariant, they must be Galilean invariant, which then returns us to Lorentz's theory, as there is no absolute reference point in Einstein's theory, so Einstein's theory is incompatible with the requirement of Galilean invariance.
In 2022, the Nobel Prize was awarded for experimentally testing quantum mechanics and verifying that quantum mechanics is indeed not wrong, and, by extension, Lorentz's theory must necessarily be the correct theory, as the existence of the rest frame of the universe has been confirmed indirectly through proving the existence of non-local effects.
Did physicists respond to this by revisiting Lorentz's ideas? No! Because to do so would contradict the last century of ideology centered around the "revolution" that is special relativity.
So, instead, physicists took a different approach. Rather than agreeing with Bell's own conclusion that his 1964 theorem shows that nature is non-local and therefore rules out "locality," they instead claim that Bell's theorem rules out "local realism."
The implication here is that you could deny locality, but you could also deny realism.
"Reality doesn't exist, but thank God it is local!"
Despite a weird common misconception I've seen thrown about, "realism" has nothing to do at all with determinism or randomness. It is about object permanence, the idea that observable objects with observable properties continue to possess observable properties even when they are not being observed in the instantaneous moment of observation.
Bell's theorem does not assume determinism; it assumes merely that at least one of the particle's observable properties still contains definite values even when not being observed, regardless of whether or not those values evolve randomly or deterministically.
The denial of realism leads directly to the "measurement problem," because it creates a disconnect between the fact that you are claiming particles possess no observable (measurable) properties when not being observed (measured), but then this fails to explain why, when we try to observe (measure) them, they always empirically possess those properties.
This has led to a deluge of incoherent, incomprehensible papers on "interpretations" of quantum mechanics which all start with the premise that particles do not possess any observable properties at all when you are not looking at them and then work backwards from this conclusion to try and desperately make it coherent.
None of them succeed in this, and they readily admit they do not succeed in this. The popularization of statements like, "no one understands quantum mechanics" are all just passive admissions that these attempts to make sense of it in a non-realist framework are simply incomprehensible and nobody even knows what is being talked about anymore.
People use these kinds of phrases in an incredibly dishonest fashion. It gives the implication that quantum mechanics is objectively incomprehensible, and that is just a fact of life. But it's not true at all.
As Bell pointed out in 1982...
[T]he subjectivity of the orthodox version, the necessary reference to the 'observer,' could be eliminated...that vagueness, subjectivity, and indeterminism, are not forced on us by experimental facts, but by deliberate theoretical choice
That is to say, the supposed "incomprehensibility" of quantum mechanics, the insistence that it is impossible to understand, the hyper-focus on the observer, measuring apparatus, stemming from its non-realist premises, are not fundamental features of the theory, but are explicit theoretical choices made by physicists.
These explicit theoretical choices all arise from a desperate attempt to preserve locality. The 2022 Nobel Prize shows empirically that, if the particles possess observable properties when not being observed (realism), the experimental results are impossible to explain unless those properties influence each other in a non-local fashion.
That directly renders special relativity non-viable. But, physicists use a loophole where they just argue the particles possess no properties when you're not looking at them.
You see, if you deny that anything exists when you're not looking at it, then the only possible way to prove non-locality is to prove non-locality precisely in what you are directly observing, which requires you to send a direct signal, i.e., superluminal communication.
Under a non-realist framework, you can't prove non-locality indirectly by showing merely that the results are impossible to explain without non-local influences if you did not directly observe those non-local influences. A non-realist framework only allows for the proof of non-locality if you can directly signal with it.
Of course, it has been proven for decades that quantum mechanics does not allow for signaling, so this loophole allows you to continue to claim quantum mechanics is local, but at the cost of denying that particles have real properties in the real physical world independently of you looking at them.
This denial of object permanence, the very basis of realism, then leads to all the absurd interpretations around the theory, interpretations which its own authors admit are entirely incomprehensible by continually repeating that "quantum mechanics is impossible to understand" over and over again.
Indeed, the complete incomprehensibility of these interpretations was proved in a paper by Frauchiger and Renner in the journal Nature titled "Quantum theory cannot consistently describe the use of itself." They proved in a simple four-qubit circuit that every major interpretation of quantum mechanics is logically inconsistent.
The only one which they analyzed that wasn't inconsistent was a realist interpretation, but when they applied this interpretation, they point out in the paper that the time-ordering of events matters, meaning you have to introduce an absolute time-ordering of events to resolve the inconsistency... meaning you need Lorentz's model.
All of this nonsense is just a desperate attempt to preserve the dominant philosophical paradigm for the last 100 years. As pointed out by Bell in his paper "How to Teach Special Relativity," Lorentz's and Einstein's views are mathematically equivalent, so changing from Einstein's to Lorentz's view does not require actually even changing any of the mathematics or the empirical predictions.
It is purely a philosophical reinterpretation of the same empirical results and the same mathematics, yet the reinterpretation allows you to avoid having to deny reality to make sense of violations of Bell inequalities, and to make sense of quantum mechanics in a trivially intuitive framework.
But, of course, if the distinction is only philosophical in nature and non-empirical, a lot of physicists just don't care, since many aren't particularly interested in philosophy and don't really care to know anything about the natural world. They are more pragmatic engineers and just want to build stuff, so they just want to know what the math says and can't care much about the ontological implications of said math.
If a person is a pure pragmatist, they wouldn't care about this debate anyway, one way or the other. So this rant is largely on the side of people who do care.
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No. Einstein stated in 1955 that he knew Lorentz's work only up to the 1895 Versuch before devising special relativity, and his 1905 paper cites nothing at all.
Source: Darrigol, "Can we trust Einstein's accounts of the genesis of special relativity?", https://www.sciencedirect.com/science/article/am/pii/S0039368121000492. Also in https://arxiv.org/pdf/2509.09361.
Not what he wrote. The concluding paragraph reads: in a theory in which parameters are added to quantum mechanics, there must be a mechanism whereby one device's setting influences a remote instrument, and such a theory could not be Lorentz invariant. The subject is hidden-variable completions, not quantum mechanics itself.
Source: https://journals.aps.org/ppf/abstract/10.1103/PhysicsPhysiqueFizika.1.195 (the conclusion is Section VI of the PDF).
Relativistic QFT is Lorentz invariant, reproduces every Bell violation, and provably cannot establish faster-than-light communication between observers. Without signaling, no frame-dependent ordering of measurements ever creates a causal paradox.
Source: Eberhard & Ross, Found. Phys. Lett. 2, 127 (1989), https://link.springer.com/article/10.1007/BF00696109
The 2022 prize citation is for experiments with entangled photons establishing the violation of Bell inequalities, which rules out local hidden-variable models. The committee's document says nothing about a preferred frame, and your own mechanism guarantees no experiment could ever find one.
Source: https://www.nobelprize.org/uploads/2023/10/advanced-physicsprize2022-4.pdf
Wrong journal and wrong result. It's Nature Communications, and the theorem states that three assumptions cannot all hold: (Q) universal validity of the Born rule, (C) consistency across agents, and (S) single measurement outcomes. Any interpretation must violate at least one. Their own Table 4 sorts the escapes: collapse models and Bohmian mechanics drop (Q), Copenhagen-type views drop (C), many-worlds drops (S). No interpretation is shown to be inconsistent. The argument itself is also contested: Aaronson rejects the claim that there's any new problem with QM's logical consistency, and Bub has a paper-length analysis of what the result does and doesn't show.
Sources: https://www.nature.com/articles/s41467-018-05739-8, https://scottaaronson.blog/?p=3975, https://link.springer.com/article/10.1007/s10701-021-00420-5
Whether "realism" is even a separate assumption is an open, published debate, which is the opposite of a taboo. Norsen argues your side (that "local realism" is a flawed phrase and locality alone carries the theorem) in Foundations of Physics. Wiseman argues that Bell's 1964 theorem needs both locality and determinism, while his 1976 theorem rests on local causality, in a mainstream journal special issue. Both sides publish freely.
Sources: https://arxiv.org/abs/quant-ph/0607057 and https://arxiv.org/abs/1402.0351
Bell did have Lorentzian sympathies, and a preferred foliation is one coherent response to non-locality. It hasn't caught on because nobody has integrated it cleanly with relativistic QFT and it posits structure that's unobservable in principle, not because of ideology.
I agree my phrasing here is not entirely accurate, but it doesn't really affect the point I am making. It is an interesting correction to the historical record, but of course my ultimately point is not about history.
You conveniently left off the very next sentence: "Of course, the situation is different if the quantum mechanical predictions are of limited validity."
The states of particles cannot be Lorentz invariant, or quantum mechanics is wrong. That's literally what it says. "The states of particles" as I say implies, you know, that the particles have real states to begin with (what you call "hidden-variables completions"), so my phrasing already correctly includes your third possibility.
What do you think "hidden-variable completions" refers to? It literally just refers to any model which specifies states of particles at all independently of observation.
You are trying to "debunk" my post by responding to a bunch of isolated statements piecemeal without context to avoid actual overarching point I am making, by making it seem like you have torn down the argument without actually addressing what I have stated at all.
These papers aren't the Bible where you just quote verses as if they are gospel. I am making an overall argument in my post and the papers serve my argument under this interpretation. If you pull the paper out of the argument and just look solely at what is literally written, yes, they don't literally verbatim say what I am arguing, but they back my argument in the context of what I am saying, unless you can disprove my preceding arguments.
You will continue to do this same tactic for the rest of your post: you will not respond to my preceding arguments, but just attack pedantically the fact that some author didn't literally say what I said, ignoring the relevance
Again, I want to stress this point since this Bell paper is a perfect example of your argument tactic.
I say: "Anti-realist interpretations are inconsistent. They lead to the measurement problem which none have solved, so I reject them. Then, Bell's theorem trivially proves that either quantum mechanics is wrong, or non-local."
You say: "Erm you're wrong the exact wording of the paper says if we accept realism, then quantum mechanics is either wrong or non-local, meaning, it does not literally say as its conclusion quantum mechanics is either wrong or non-local!"
Notice your argument tactic: It's clear in the broader context of my post that the paper backs my claim in the broader context of what I am arguing, but you want to hyper-focus on whether or not the author literally wrote my exact statement for what I am referencing the paper for, rather than actually rebutting my point in the context of the argument.
Signaling and non-locality are not the same things, you are conflating two different concepts. The non-existence of signaling does not imply there is nothing non-local, and the non-locality in relativistic QFT has been proven to lead to paradoxes.
Okay... but I know, you will say, "it only mentions the time-ordering of events mattering under realist interpretations, so the paper doesn't back what you say!" Yes but... again... I am rejecting non-realist interpretations.
Bringing up relativistic QFT is also largely irrelevant, because we are not talking about mathematical models here, but interpretations. This is, indeed, a prime example of ideology: you are conflating math with interpretation, as if the very existence of a mathematical model making reliable predictions automatically proves beyond doubt your philosophical interpretation of the ontology stemming from the mathematics is correct.
It does not. I am not denying the mathematical model. That is an incredibly disingenuous implication, and is a common tactic of the ideologue. They want to pretend math = interpretation and so anyone who disagrees with the dominant interpretation, the dominant ideology, must be rejecting the math and be "anti-science," which is your implication here. I am not rejecting the mathematics of relativistic QFT at all or contending it at all.
I am contending the interpretation placed on top of it.
Again, if your argument is that it "rules out local realist models," then you need to justify how your anti-realist stance can be made logically consistent.
You are not doing that. You are missing the entire point of my post, which is that quantum theory trivially demonstrates non-locally, and as a coping mechanism to get out of it, people like you point out that, "well, quantum theory only rules out non-locality in reality, but if we deny reality, then we can avoid non-locality!"
But denying reality is something I do not find logically consistent, and no one has ever made it logically consistent, because it directly leads to the measurement problem which has no coherent solution in the literature.
But you will just respond saying "it does have solutions!" without justifying them. You just say things confidently without engaging in any of my points.
If a preferred frame exists and the mathematics of special relativity is perfectly correct as written, you could not detect the specific rest frame, but you could still detect whether or not one exists, by demonstrating the existence non-local effects.
This is just needlessly pedantic.
If you actually read the paper, you'd understanding it "drops Q" because, as the paper states explicitly, the time-ordering of events matters in Bohmian mechanics, and therefore the Born rule alone is not sufficient to specify the ontology of a physical system.
Again, you are not engaging with my actual argument in my post. You are intentionally responding to random isolated points piecemeal to avoid the bigger picture of what is being said and to ignore the context of what I am writing.
I am rejecting anti-realist interpretations as consistent, and this was a statement that, if we accept realism, then you need an absolute time-ordering of events.
Sure, if you want to drop the view of consistency... go ahead. You would just be admitting my point that it is not consistent.
Again, I am rejecting non-realist interpretations for being logically inconsistent, so I am rejecting Many Worlds as a possibility.
If you think Many Worlds is consistent, you should argue and defend that, not engage in this decontextualizing quote-mining exercise that intentionally is just avoiding having a serious discussion.
If you think Many Worlds is a consistent and defensible point then your post should focus on that.
You literally quoted one where what is dropped is consistency between agents...
Yeah, the blog post is wrong.
I actually prefer the phrase "local realism" over "local hidden-variables," because the latter is incredibly misleading. The term "hidden-variables" implies you are adding something invisible to the theory, usually people falsely assume is for the purpose of restoring determinism.
But the discussion has nothing to do with determinism or introducing anything invisible. Neither of these are assumptions in Bell's theorem. The assumption is merely that of object permanence: that the kinds of observable properties we observe in experiments of particles, at least some of those properties continue to exist even when not being observed in the instantaneous moment of observation.
Human brains are also made up of particles, so if you deny that particles possess definite properties when not being immediately observed, then you run into the risk of devolving into solipsism, as now other human brains do not have definite mental states when not being observed, and this risk is directly what the paper by Frauchiger and Renner bring forth explicitly, something you have not explained to me what you believe is the way around the risk.
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If that is what he is actually written, then he is just trivially wrong and this is not even controversial, as determinism is not an assumption in Bell's theorem at all. The Reichenbach factorization within Bell's theorem only requires you to presuppose that the particles possess definite values at all when they first interact. It does not, in any way, presuppose that those values need to evolve deterministically.
Determinism/nondeterminism is simply not relevant to Bell's theorem. There are non-realist deterministic interpretations (MWI), non-realist nondeterministic interpretations (RQM), realist deterministic interpretations (Bohmian mechanics), and realist nondeterministic interpretations (unistochastic dynamics).
Realist nondeterministic interpretations still are subjected to Bell's theorem, they still run into the issue of the states of the particles not being Lorentz invariant.
Simply assuming that the real states of particles evolving randomly does not escape the non-local features of quantum mechanics. It is an inevitable conclusion from assuming that particles possess definite values independently of observation at all, regardless of whether or not they evolve deterministically or randomly.
There isn't another response in the literature, because it is just a mathematical fact that non-locality is not compatible with special relativity.
The opposition is not to accept non-locality and claim somehow it does not require a preferred foliation, but instead to deny non-locality by denying realism.
People like yourself who falsely claim that QFT has been proved to be consistent and local. But the truth is you have not solved the measurement problem. Here is a poll among academics on solutions to the measurement problem: https://arxiv.org/abs/1301.1069
None include "QFT solves it" as a solution. And there is no agreed upon solution at all, no category even has majority agreement, only plurality. QFT obviously does not solve the problems I've brought up, and Einstein was well aware of this, which is why he spent the rest of his career trying to develop a local field theory formulation of quantum mechanics.
QFT is a field theory, but it's clearly non-local, as it still violates Bell inequalities. No, being non-local doesn't mean you can signal. I'm obviously not claiming that, to pretend I am is disingenuous. It is both non-local but also no-signaling.
I am not contending with the mathematics of relativistic QFT. Stop with this ideology of pretending that the mathematics inherently carries your ideological interpretation so if I question your interpretation of the mathematics I'm somehow denying the mathematics. The mathematics are not the issue, but this is a philosophical discussion: the issue is ontological consistency in how you interpret the mathematics.
Again, we've been over this already.
Saying "it's unobservable" is not, in isolation, a sufficient argument, if dropping the assumption leads to inconsistencies.
I am saying it is inconsistent to drop it, and so just repeating this point over and over again doesn't establish anything.
I literally acknowledged openly and explicitly in my original post that it is not directly detectable, and that isn't my argument that it is, my argument is that it is necessary for consistency if we assume (1) realism and (2) quantum mechanics is correct.
Constantly going back to saying "it's not directly observable!" is just going back to a list of talking points and not honestly engaging with my argument.
It's obvious you probably just asked AI to quote-mine a bunch of sources as a rebuttal, because you think a big list of citations make it seem like a "smart" reply (and indeed I'm sure a lot of people will fall for that). But if you actually understood this topic, you would not need to cite a single paper at all. You could just engage directly with the arguments and the mathematics.
Your post not only does not do that, it is precisely structured to avoid doing that, like saying, "look, this blog post disagrees with you, so you're wrong." Obviously, I am aware of Aaronson's blog post, read it, and found it unconvincing. I'm not going to respect that further than saying, "the blog post is wrong," because you're not actually engaging with anything I'm writing, but attempting to cherry-pick with various appeals to authority and references you don't understand to "debunk" it while not actually engaging directly with any of my points.
If you understand what is being talked about, then you should make the arguments, in your own words. You should be able to repeat his argument and defend it and show how it resolves the problems I mentioned in my post (problems which conveniently, by cherry-picking quotes from post, you entirely ignore and treat my statements in isolation as if they were not connected to a broader argument in a broader context).
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Dude, I think you win, but this opinion is unpopular due to lack of general knowledge and exposure to this subject.
Kind of but not really. Yes, it's not popular among laymen, but even among academics it is generally unpopular due to, as I stated:
When I talk about "realism" here I am talking about object permanence. Someone might try to argue that they believe in a "reality" without object permanence, but my position is that none of these viewpoints have been shown to be logically consistent and I remain unconvinced by all of them.
I think, ultimately, that's the position that is in a minority: that most people, even academics in the field who understand this quite well, either don't care about philosophy at all so they don't care about this discussion to begin with, or if they do care, most think it is possible to make sense of a reality without object permanence.
But I have read all the major papers and I remain unconvinced.
The only view, besides mine, I think is even logically consistent are objective collapse models. They, like Copenhagen, blatantly contradict the mathematics of the theory, but they openly just accept that, admit that they do, and specify rigorously how this deviation occurs. I think they do succeed in constructing a coherent model, one that replaces typical object permanent ontology with what Bell called a "flash ontology."
But they come at the cost of having to say "quantum mechanics is ultimately wrong on some level, and an approximation for a deeper theory." I'm not ready to make that commitment, I think quantum mechanics is correct, and so, assuming quantum mechanics and object permanence are correct, the only viable option is the one I have outlined.
Object permanence seems like a real distinction, not a philosophical one.
The thing is, "reality," and thus what is "real," is itself a philosophical category.
You can be a physicist and not even believe reality exists, you can be a complete solipsism, because ultimately all that is required to be a physicist is to understand the mathematics and be able to use them to make correct empirical predictions to what you will observe. I strongly believe in realism and believe object permanence is also indispensable to realism. But this is a philosophical position. I don't believe I can prove to a non-realist that realism is correct.
I do readily admit that a lot of my points here require you to already agree on some philosophical premises. If you don't share certain baseline philosophical assumptions, then I could not demonstrate to you that the things I am mentioning here that I believe are problems are indeed actually problems.
Indeed, there are a lot of physicists to take a "shut up and calculate" mentality, which is that, all that ultimately matters is the practical, pragmatic, empirical predictions at the end of the day, and talking about "reality" and "what is real" is just a waste of time and is abstract metaphysics. If you are not already on board with caring about those things, then I cannot convince you to come on board, and ultimately none of this post would be applicable to you.
That is really what I mean by saying it is philosophical.
I guess in my mind the argument is already settled. I think therefore I am. To argue otherwise is absurd. So while reality may be inferred from thinking, it cannot not exist when thought exists. I don't think we will find anyone who can argue successfully that thought doesn't exist and I don't see anything philosophical about that. If that's philosophy then so is all science.
To be a physicist and not acknowledge this sounds like a failure of the mind, but perhaps we are then discussing some similar concept and not the same thing?