The Defeat of Reason?
Niels Bohr brainwashed a whole generation of theorists into thinking that the job of interpreting quantum theory was done 50 years ago.
Dr. Murray Gell-Mann
Re-reading Tim Maudlin’s famous book review at Boston Review on the fundamental problems of modern physics and of the enterprise of reason itself in relation to two noteworthy books gave me the opportunity to reflect on my own thoughts, half formed, on this subject which I have entertained for a while.
In the course of development of a technologically advanced society a well informed individual at the dawn of the 20 century would likely have believed that the scientific theories developed thus far and those to be developed would eventually advance likewise in sophistication, internal correctness, and correlation with observable reality, leading to ever greater predictive models. Which can then be applied to the practical arts in the form of engineering, political economics, social development, and human-societal uplifting. With the positive feedback loop reinforcing and accelerating the pace of development.
Certainly this was the expectation of many by the mid 20th century.
Now from the perspective of 2022 we can confidently analyze the events of the preceding century on Earth using retrospective and counter factual comparison and come to the conclusion that events did not develop entirely along a straightforward progression.
The reason why can be seen through the lens of the stagnation and profound contradictions of fundamental physics that has developed in the last few decades, or Maudlin so implies. Thus, we approach the first book:
The title of the first book is self explanatory: What Is Real?: The Unfinished Quest for the Meaning of Quantum Physics by Adam Becker
The theory reminds me a little of the system of delusions of an exceedingly intelligent paranoiac.
Albert Einstein on Niels Bohr’s theory (later becoming the Copenhagen Interpretation, which became commonly accepted as the default view on quantum physics )
Most notably in the field of physics, according to Maudlin, the stagnation is both profound and inexplicable according to the commonly accepted Copenhagen Interpretation, some may say even necessitating an anti-intellectual and anti-rational mindset to resolve the contradiction. This theory was developed by Niels Bohr and his followers in the first half of the 20th century, with later refinements eventually installing the theory as the textbook, the default, interpretation of physics.
Personally, as it’s highly unlikely that the universe is actually divided by some mysterious boundary between the domain of quantum mechanics and the domain of general relativity, nor between regular matter and some type of special ‘observer’ matter, the temptation to reject the Copenhagen interpretation and redevelop foundational physics along some alternative line is obvious and a clarion call for contrarians. It is these contrarians that provide the narrative impetus for the book.
In the new, post-1925 quantum theory the ‘anarchist’ position became dominant and modern quantum physics, in its ‘Copenhagen interpretation’, became one of the main standard bearers of philosophical obscurantism. In the new theory Bohr’s notorious ‘complementarity principle’ enthroned [weak] inconsistency as a basic ultimate feature of nature, and merged subjectivist positivism and antilogical dialectic and even ordinary language philosophy into one unholy alliance. After 1925 Bohr and his associates introduced a new and unprecedented lowering of critical standards for scientific theories. This led to a defeat of reason within modern physics and to an anarchist cult of incomprehensible chaos.
Imre Lakatos
Einstein, Schrödinger, and several other notable physicists at the time disagreed with Bohr and his followers. Yet tragically none of them lived long enough to develop a complete alternative interpretation, leaving only scattered puzzle pieces.
And the defenders of what later became the widely accepted theory were quite persuasive in labelling any contrary theory as unknowable, undecidable, beyond the realm of physics, metaphysics, etc. Even von Neumann weighed in and wrote a paper concerning a mathematical proof that supposedly proved that quantum mechanics is complete and one could not add anything more to it and retain its successful predictions.
Thankfully, an interesting fellow named David Bohm, originally a Copenhagenist, defected and sought to prove the alternative theory left unfinished by Einstein. He was also the one who published the refutation of von Neumann’s paper.
Bohm rediscovered the pilot wave theory that Louis de Broglie had presented at Solvay in 1927. The theory slices through the enigma—wave or particle?—like Alexander’s sword through the Gordian knot: the answer is wave and particle. The wavefunction becomes a pilot wave that guides the particles along their paths. The theory is completely deterministic—no playing dice—and recovers all the predictions of standard quantum mechanics. One would think Einstein would love the theory, but he did not. The dreaded nonlocality had not been exorcized. Indeed, it was even more striking.
Tim Maudlin
Although a non-local physics was viewed as preposterous at the time, most notably by Einstein himself (‘spooky action at a distance’), later developments seem to have established very convincingly that a non-local interpretation is the only way forward. You may be surprised that such a revelation did not immediately precipitate a revolution in physics, but the same dynamics that ensured preeminence of Bohr’s theories in the first place likewise subsequently hand-waved away even the most expertly presented refutations.
If we cannot disprove Bohm, then we must agree to ignore him.
Robert Oppenheimer
Hugh Everrett and later John Stewart Bell took on the contrarian’s mantle and sought to decisively disprove, or in modern terms debunk, Bohr and his followers. Although they were hardly rewarded for these efforts during their lifetime, their work subsequently became the basis for Many-worlds theory, Bell’s inequality, and their intellectual descendants.
The last third of What Is Real? could hopefully be titled “Slow Convalescence.” Gradually the worst excesses of Bohr’s influence are mitigated as Bell’s work inspires a new generation to look into foundational issues. We meet a new cast of characters, and the overall atmosphere is mildly optimistic. But there is a long way to go, and this very book could prove to be a watershed moment for the physics community if it faces up to its own past and its present. Or, following the fate of Einstein, Bohm, and Everett, Becker could just be ignored. But if you have any interest in the implications of quantum theory, or in the suppression of scientific curiosity, What is Real? is required reading. There is no more reliable, careful, and readable account of the whole history of quantum theory in all its scandalous detail.
Tim Maudlin
The change in physics seems inevitable as the need to bridge the divide between large scale and small scale structures grows more pressing. The nature of such a change however presents its own logic and attendant issues.
This leads into the second book: The Ashtray: (Or the Man Who Denied Reality) by Errol Morris
Within is presented an explanation on the possible motivations of why an alternative path of scientific, philosophical, and technical development was ultimately taken on this Earth to begin with in the narrative form of a recounting of Thomas Kuhn’s story. And this was not obvious at the time as nearly all signs pointed to a continuous and unalterable uplifting trajectory.
The resulting consequences for broader society are touched upon, along with interesting remarks by the reviewer.
Namely that Thomas Kuhn’s well known theory of ‘paradigm shifts’ ultimately leads to a conclusion not commonly discussed but inevitable if one were to maintain logical consistency:
Kuhn believed that we can do no better than miscommunicate, misunderstand, and ultimately resort to raw institutional power to resolve our disputes.
Errol Morris
In game-theoretic terms, as pathways to positive sum games, and possibilities for discovering more thereof, were slowly circumcised by the philosophical and scientific stagnation that appeared in the mid 20 century, first in the most abstract fields and eventually in ever broader intellectual directions, the defeat of reasonable and rational cooperation became inevitable.
The consequences of such a development redirected human efforts from pursuing positive sum games into pursuing zero sum games or destructive games. The attendant effects of which we are now observing progressing in amplifying and mutually reinforcing spirals.
The destructiveness of such a course of action has been precipitated by and obscured among the educated elites, the decision-makers, and broader society, via many mechanisms, of which the reviewer believes acceptance of certain elements of Immanuel Kant’s radical philosophy, such as rejecting an external world unconnected with internal mental processes, was the prime instigator.
In short, Tim Maudlin summarizes the consequent result of the acceptance of these peculiar theories and their logical implications:
When the Copenhagen interpretation got imported to the pragmatic soil of the United States, Bohr’s incomprehensible nonsense was replaced by the more concise “shut up and calculate.” That is the philosophy that dominates physics to this day.
What of Kuhn? He was quite explicit about his relationship to Kant. Late in his life, Kuhn declared, “I am a Kantian with movable categories.” That is, he embraced Kant’s thesis that the mind imposes structure on the experienced world rather than discovering structure in it, but, contrary to Kant, the imposed structure can change. Such a change is a paradigm shift, the ultimately irrational replacement of one experienced reality with another incompatible one. Caught in our own little thought-worlds, deprived of access to objective truth (because there is no objective truth), we can do no better than miscommunicate, misunderstand, and ultimately resort to raw institutional power to resolve our disputes. As appropriated and mangled by Bohr and Kuhn, Kant—despite his own embrace of science and reason—becomes the agent of the anti-Enlightenment, the post-truth Age of Spin and Branding we live in.
Tim Maudlin
Although Maudlin presents a convincing story of the origin and propelling forces of the deviation from the theoretical ideal we have observed over the recent past, there have been developments contrary to the trend of stagnation. Notably in the biological, mathematical, and computer sciences.
Why stagnation was avoided in these domains remains unexplained though perhaps a few interesting clues may lead future geniuses to develop into a general theory and allow future historians to clarify the pattern of development of human societies. Such as:
The replacement of computer science research largely by metamathematics in academia, and thus the mass migration of computer science research into industrial and commercial organizations beginning in the 1970s may have contributed to the fecundity and diversity of subsequent developments relative to physics.
The astonishing growth in the sophistication of instruments, manufacturing, and our knowledge in their use, popularly expressed by Moore’s laws and by even more extreme growth in biological genotyping, have allowed for theories to be tested and compared using brute force means in addition to observation and logical argumentation.
The greater market demand for quality of life improving products and services as opposed to large military production since the end of the Cold War. Favouring feedback cycles targeting smaller scale, lower cost, ease of use, etc. Which benefit certain types of developments over other types.
cross-posted from my blog
It’s hard to regard physics since Bohr as stagnant, when that same period gave us the standard model (and then string theory, which physicists do generally regard as a great advance, but not one that has yet become testable). Maybe the positivistic quantum theory of Bohr has to reach the era of gauge fields and branes, before the right postquantum ontology can be identified.
Some say string theory is even less testable than some of the more sophisticated proposals for many worlds, transactional interpretation, or some of the retrocausal interpretations, assuming some type of ‘spooky action at a distance’, etc., is inevitable. So it does not yet seem clear that it will prove to be an advance at all. Especially as delayed choice quantum ‘eraser’ experiments have been delivering quite interesting results in recent years that although not necessarily refuting Copenhagenists certainly introduce bizarre complications into their model. See https://physics.fullerton.edu/~hal/Delayed-15.pdf
There’s more to physics than the general quantum-mechanical framework. There is the specific ensemble of forces and particles that we find in nature, with all their various properties, including quantities like masses and couplings. The standard model tied most of that into a single equation, using the new concept of gauge fields (Yang-Mills); and string theory gives us a framework of possible worlds in which such quantities take definite values in each world, and it does so in a mathematically deep way. Those two steps each constitute enormous progress.
The “Copenhagen interpretation” is the one way that we know how to use quantum theory, that actually works; while the other interpretations are ontological ideas of varying degrees of vagueness, whose viability has to be tested against the best specific theory we have, and which are, so far, all lacking in some way.
I don’t think it was ever in question there’s more to physics than the ‘quantum-mechanical framework’? I am not quite sure what you are trying to get at with the first paragraph. Surely it should be clear by now with regards to advances in neutrino physics, etc., that the standard model is incomplete? It could very well be that some future advancement will make string theory redundant or require modifications, etc.
And in any case by no means are ‘gauge fields‘, ‘string theory’, etc., widely accepted as general relativity for example (which in itself has different camps of supporters on certain matters), or widely accepted to have constituted ‘enormous progress’, that is after all why there is even a serious audience for the first book.
In regards to your second paragraph, I will make my remarks clear, the delayed choice quantum ‘eraser’ experimental results have conclusively shown, at the very least, that the Copenhagen interpretation, and slight variants thereof, do not produce the most parsimonious results. Of course that does not constitue a refutation either as the equations ‘still work’, but they certainly have convinced and continue to convince serious people that there’s more to the story. And it’s the meaning we attach to those equations that allow for an integrative understanding, they may indeed be ‘ideas of varying degrees of vagueness’ but that includes all interpretations.
For example, the fact that the Schrodinger equation, in linear or nonlinear forms, ‘works’, does not automatically imply that the current theory, of anything involving the equation, is more privileged than some other theory. Unless experimental results decisively falsify said theories.
That physics has not stagnated.
This is a gap in your understanding. Unlike string theory, gauge fields are at the heart of empirical progress in modern particle physics. All the forces other than gravitation are described by gauge theory. (Maudlin has even proposed that the fiber bundles of gauge theory offer a new approach to metaphysics, an alternative to universals. I don’t know if the idea makes sense, but it’s creative and engaged with the facts.)
The parsimonious approach to all quantum experimental results is the one which interprets them in terms of observable properties being described by Hilbert space operators, the quantum probability calculus, etc. Yes, if you want a theory that tells you what reality is, in a way that doesn’t refer to observation, you’ll need something else. You are welcome to develop the ideas of Bohm, Everett, Penrose, Cramer, etc. But none of those theories is presently good enough to replace quantum orthodoxy.
I don’t think any reader of LW believe physics in general has stagnated? With recent developments, well covered in mass media, in gravity waves, neutrinos, cosmology, etc., I don’t think there’s anyone with honest intentions in danger of genuinely believing no progress in physics has occurred at all.
Is there some hidden danger you’ve spotted?
On ‘gauge fields’ like I said the theory is nowhere nearly as widely supported as general relativity, which I use as the reference point for ’enormous progress’, among many examples. Considering that there are fringe people that reject even the ‘empirical contribution’ it should not be a surprise that the set of people that reject either the ‘theoretical or empirical contribution’, or some other aspect, is larger.
Your final sentence seems logically unrelated with the quote?
EDIT: I realized you may have thought what I wrote were not Maudlin’s thoughts but my own, therefore I will state that I personally don’t believe physics in general has stagnated. And I will edit the essay to make it clear.
Who are these people that reject gauge theory? I wonder if we’re talking about the same thing. If I look at the list of Nobel Prizes for physics, I see prizes for gauge theory awarded in 1979, 1984, 1999, and 2004, and probably we should count a few other years like 2008 and 2013 too. In a modern understanding, even plain old electromagnetism is a gauge theory.
In the final quote, aren’t you saying that we already have better theories (more parsimonious) than quantum mechanics under the Copenhagen interpretation? Because that’s what I’m disagreeing with.
Hmm I guess if you consider electromagnetism as part and parcel, i.e. as a general theory of fields then I would agree. Perhaps it can be considered to be nearly universally accepted if so, though in that case it seems less like a new theory and more like a refinement of existing theories. I had in mind, to what you were referring to, a more limited scope of gauge fields as they apply to the more controversial QM foundational work, though perhaps you would consider those as tenuous extensions and not gauge theory proper.
We have experiments that demonstrate something other than the CI has the most parsimonious explanation, for that experiment. That doesn’t automatically imply such theories are more parsimonious overall. But it does imply there is a possibility.
I’m still not sure if we understand each other regarding the gauge fields. Do you agree that gluons, and W and Z bosons, exist? They are described by Yang-Mills fields, i.e. a kind of gauge field. They are gauge fields with nonabelian symmetry groups, whereas a Maxwell field like the electromagnetic field is an abelian gauge field.
The explanation of nuclear forces in terms of gauge fields was certainly fundamental progress in physics. But it is not generally understood as a change in the interpretation of quantum mechanics, though it does present specific new challenges, e.g. a Bohmian gauge field would seem to require choosing a particular gauge as the ontologically correct one, in the same way that Bohmian quantum fields in general require a preferred reference frame; and in both cases this is somehow against the spirit of the symmetry in question (gauge symmetry, Lorentz symmetry).
I don’t agree that there are particular experiments where one of the ontological interpretations offers the most parsimonious explanation. In the link you gave, it’s claimed that the transactional interpretation offers a more economical explanation of the delayed choice eraser. I don’t see it. To begin with, there doesn’t seem to be any clear principle telling us how to analyze a given experiment in terms of advanced and retarded waves. It seems to be up to the interpreter to figure out a story about which waves go where. I also don’t really understand how the Born rule emerges in the transactional interpretation. (But perhaps there are principles behind both of these, and I just haven’t seen them.)
By contrast, an instrumental or phenomenal or positivist approach to quantum mechanics is quite straightforward, because empirically it just boils down to conditional probabilities connecting observed events. It’s also more flexible because it doesn’t even require wavefunctions; it’s just as valid for a different formalism, like Heisenberg’s operator algebras. The downside is that it’s not giving you an observer-independent ontology.
I didn’t just say Copenhagen interpretation, because in people’s minds, the Copenhagen interpretation is often loaded with hermeneutic ballast that I might not agree with. So all I’m saying, is that an interpretation of quantum mechanics, which focuses on observed properties and makes no ontological assertions about anything else, is the most parsimonious interpretation we have.
My view on transactional interpretation, many worlds, etc., is that they are interesting and suggestive, but they all still have deficiencies when it comes to accounting for the full range of applications of quantum mechanics.
Sorry for the late reply,
After some reflection I would have to say that most of what you write is sensible stuff. Though the definitions are the tricky part, like most discussions of physics when they get down into the weeds.
It is clear that something akin to gluons, W, and Z bosons must exist for the most elegant explanation, otherwise ridiculous complications will need to be introduced to fit observed phenomenon. But there’s always the danger of falling into the trap of thinking of these ‘objects’ as discrete entities, which I am not entirely convinced of. And so I will refrain from using the word ‘exist’.
If you mean ‘exist’ by a discrete object with a unique position persisting across some span of space-time, I’m not entirely sure they do.
Fields, or something akin to fields, clearly do, and so do macro objects of course, but I’m not even entirely convinced that electrons ‘exist‘ in the same sense as the above. They may ‘exist’ in the sense that information ‘exists’.
There‘s also Feynman’s half-in-jest proposal of a one electron universe, which I think has a grain, or several grains, of truth. If that helps you better understand my position.
Hermeneutic ballast is an excellent term! It’s definitely a more concise way of describing its oddities.
Ontological assertions may be avoidable even if some combination of ’spooky action at a distance’, ‘hidden variables’, etc., proved to be the case, but I just don’t see how anyone could make the argument without sacrificing parsimony.
And it seems ever more likely for that to be the case in the reality we live in, given recent trends in cosmology and black hole physics.
I think you (and possibly Maudlin) got it all wrong. No one likes the “shut up and calculate” non-interpretation. Sadly, it’s the only actionable one, since frequentist probabilities is the only measurable quantity. The Bohmian pilot wave stuff does not add anything interesting, and MWI is nowhere near testable levels. Dynamical collapse due to gravity might become testable soon though, with the “gravcat” states are almost within experimental reach. There is a resurgence of interest in the foundations of QM, see recent work by Sean Carroll, for example, and a recent discussion on Scott Aaronson’s blog. Basically everyone admits that any theoretical progress would require a Kuhnian paradigm shift of epic magnitude, not seen for a century or so.
The issue is not that theorists went off on a wrong path somewhere. It’s that there is no clear “right” path in sight, and every promising avenue of advance faces extreme theoretical and conceptual obstacles.
The logical consequences of Bell’s inequality being violated seems to imply non-local forces or perhaps even more mysterious things are in fact going on. Or alternatively some form of superdeterminism.
I am partial to superdeterminism, as well, since I believe the world being deterministic, but there is no good model of superdeterminism at present that gives rise to Bell inequalities. In fact, it would be far easier to come up with a classical superdeterminism than with quantum one.
Then why do you believe I, or Maudlin, got it wrong? None of what you’ve written suggests there’s a contradiction or factual error. Is there a specific sentence that is incorrect in my essay?
The catchy title “The Defeat of Reason” has no resemblance to what is going on in fundamental physics research.
There was never an experimental “refutation” of the objective wave function collapse, the issue its obvious incompatibility with relativity, hence the instrumental approach of calculating probabilities until the deep fundamental questions get resolved (they haven’t been, and not for the lack of trying). Understanding decoherence got us to the diagonalized density matrix, but the last step, selecting a single eigenstate, is still an unresolved issue.
Yep. Decoherence is not simple.
Yes, I totally agree that the catchy title was editorializing by Boston Review, that’s why I put a question mark at the end.
I never specified there were experimental refutations of ‘objective wave function collapse’. The difficulty is obvious as by definition an observation can not be refuted just by saying so, therefore I agree there likely won’t be some genius post doc who will wrap everything up in a bow, it’s likely a long road ahead to reconcile the difficulties.
Specifying the difficulties on some basis more objective than “I just don’t like it” would be a good start. You’re never going to satisfy everyones’s subjective preferences.
What proof do you have for your assertion that there’s no objective basis?
The various people you are quoting keep failing to say what is so bad about indeterminism, etc. That doesn’t mean no one can. In any case, you keep saying that you don’t agree with them, leaving us wondering why you quoted them.
Because trying to understand both sides of an argument is common practice? Not sure what else to say if you somehow don’t recognize that as valid.
It’s hard to tell whether you are asking whether there is a problem with QM, or saying that there is . One would expect a question to be brief.
If you wrote this at the beginning then we wouldn’t have had to go back and forth.
Your concern is understandable, if you wish to learn more about the fundamentals of the topic you can refer to texts aimed at a general audience.
You didn’t say which though, did you?
Which of what?
“Whether you are asking whether there is a problem with QM, or saying that there is”
It doesn’t seem like you are asking a question or making an inquiry but if you really do mean to then the possibilities could include both, neither, or something else. Why do I have to pick one or the other?
I’m answering a question.
Because only you know. We got into the topic because people responded to your OP as though it was ,but you stonewalled them by saying that you didn’t actually support any of the arguments and claims you went to the trouble of citing. At this stage, no one knows how to make an object level response, and no one is making one. Is that what you wanted?
If you were not raising a question, then what is your above question in relation to? If it was a rhetorical question then you worded it in a way that suggests there is a binary choice, somewhere.
You (or Maudlin or somebody) need to explain what is so terrible about non locality and indeterminism. I don’t buy arguments from “visualisation” because I don’t see what’s so special.about the human visual system.
There is nothing ‘terrible’ about non locality. Was that implied somewhere? (Maudlin implied Einstein thought it was perhaps ‘terrible’ though it certainly doesn’t seem like he shares the sentiment, nor do I)
If you object to neither indeterminism, nor non-locality, what is the problem?
Please don’t answer “it’s irrational”.
You were the one who started this comment thread? What are you inquiring about?
If you are confused about what Maudlin believes the problems are I would recommend reading his review. In short he seems to have believed there are many problems in many different aspects of fundamental physics and the progress of science, though since I don’t know the man personally I wont presume to know more.
I did read the review. In the review , he treats indeterminism and non locality as bad things that need to be avoided. But he doesn’t say why. So I don’t think the review me few anything (none of his other points are strong either).
If you don’t think the review contains anything valid, why did you post it?
You appear to not understand the comments I have left, or his essay, or both. He does not express a problem with ‘non locality’ or ‘indeterminism’, as far as I can tell. He references OTHER people who seem to have such a stance.
It doesn’t matter who says it, it matters whether it valid or not.
It doesn’t matter who says it, it matters whether it valid or not.
Then why do you think the review is ‘invalid’ if you acknowledge the author doesn’t share the opinion?
It matters whether the argument is valid. Validity comes form the argument, not the person making it.
Yes, so you understand that reviews cannot be ‘valid‘ or ‘invalid’ independent of the arguments advanced within them? And you understand that neither the original author, nor myself, advanced an argument about the ’terribleness’ of non-locality, indeterminism, etc.? Then everything should be clear?
I vote for changing the post title, it is clickbait. OP: it may be a factor behind the low upvotes. Also that the body is not well structured. Impossible to skim to get an idea what it’s about.
I have not asked for any ‘votes’ on regards to the title. If you wish to express dissatisfaction the polite way would be to do so directly instead of through clever rhetoric.
For example: “The title dissatisfies me because of xyz reasons.”
Whether or not the essay attracts a large audience is irrelevant for me.
I’m sorry, I did not mean to be clever.
You seem to be conflating the Copenhagen interpretation with objective reduction. The minimal CI doesn’t make any positive ontological claims. As such it is hard to refute...it entirely agrees with the evidence , and contains nothing extraneous (unlike Bohm ’s theory!)
https://www.lesswrong.com/posts/4PpQ2jyE9LxvsrCsc/schroedinger-s-cat-is-always-dead?commentId=AG8bmFzXALPK4doBk
What is ‘objective reduction’? Do you mean https://en.wikipedia.org/wiki/Objective-collapse_theory ?
If so why do you think I am conflating them?
I certainly don’t think the modern understanding in any of the interpretations I, or Maudlin, mentioned is that a thing called ‘consciousnesses’ forces ‘collapse’, if that’s what you are trying to imply.
Consciousness Causes Collapse is different from Objective Collapse is different from Copenhagen Interpretation.
In this passage …
You link the CI to observers having a special role .
I still don’t get why you linked to that strange comment. Why bother if it has nothing to do with what you wish to inquire about?
If you intended to inquire only about this so called ‘Objective collapse’ theory that is one thing. But I don’t see the logical connection between that and me stating there’s a special role for observers in the commonly accepted variations of the Copenhagen Interpretation. That is perhaps the special feature of CI, although obviously not the only differentiating factor.
There are multiple speculative theories on the implications of having an observer in regards to QM, etc., of which it seems ‘Objective Collapse‘ theory belongs to. It certainly isn’t the only possibility. I don’t have any preference for any of these theories at all, in fact I haven’t even heard of this specific theory since I personally don’t work in the field and thus have no position to advocate or defend.
The CI.states that observers make observations that are classical in a certain sense, such as being real-valued. It doesn’t say that they cause anything, or that the WF is real..and therefore doesn’t need to say that the WF needs to be collapsed.
I agree, the special role of the observer in CI does not necessarily extend to any ’must cause something’, ‘need to be collapsed’, ‘xyz must be real’, etc., theories. Many theories argue the existence of the observer must imply x or y or z, or some combination thereof, but that’s not what this essay is concerned with nor do I endorse any specific theory.