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MWI vs Copenhagen Interpretation

  1. Dec 24, 2011 #1
    I recently read an article entitled, "The Interpretation of Quantum Mechanics: Many Worlds or Many Words?" authored by Max Tegmark and it raised many questions on the matter as well as curiosity. In the article, Tegmark provides two tenable but diametrically opposite paradigms regarding physical reality and the status of mathematics and they follow:

    Which of the two paradigms do you find more.. agreeable?
    And on that note, what are your thoughts on quantum suicide? I kind of understand it but some different views and clarifications would be better.
     
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  3. Dec 24, 2011 #2

    Hurkyl

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    My first thought is that the opposition is artificial. There are four paradigms: you could label both views as being 'physically real', and you could label them both as being approximations.


    But really, from the little bit you've presented, it just seems... like he's missing the point. The inside view is a mathematical structure too. And in a mature theory, the inside view and the outside view aren't even different structures -- they just place emphasis on different parts of the same mathematical structure.


    What is "subjectively perceived" is something else entirely, although one of the primary purposes of a theory is to try and put words to it. The inside view is designed so that if you are using a theory's words, you need the words of it's inside view. (but it's often easier to understand when phrased in the outside view's words instead)


    It's a bit of a problem that the phrase "X is physically real" is somewhat ambiguous. It's already ambiguous in natural language (just what is 'X' referring to) -- when we're talking physics there's another layer of indirection that may be involved.

    But hopefully you'll understand what I'm about to write anyways. The usage of the phrase "X is physically real" that I'm used to in this setting is that X is a property of the mathematical structure, and the theory asserts there is some sort of experiment one can perform (at least in principle) whose result corresponds to the 'value' of X.

    e.g. Newtonian mechanics posits that "The x-coordinate of an object" is not physically real. However, "the distance between two objects divided by the length of a meter-stick" is physically real. (or, at least, closer to being physically real)

    With this understanding of the phrase "X is physically real", then any aspect of a theory that is "physically real" ought to be part of the inside view.
     
  4. Dec 24, 2011 #3
    Okay so the phrase "X is physically real" asserts "X" is real only if an experiment can be performed to proved as so.. I get that.

    Well, the first paradigm -which Tegmark terms as "Platonic paradigm"- all of physics is ultimately a mathematics problem, "since an infinitely intelligent mathematician given the equations of the Universe could in principle compute the inside view," i.e. compute what self-aware observers the Universe would obtain, what they would perceive and in what language they would invent to interpret their perceptions, and thus in this paradigm the axioms of the "Theory of Everything" is purely mathematical axioms. And the second paradigm he proposes, there cannot be a Theory of Everything "since one is ultimately just explaining certain verbal statements by other verbal statements" (which is known as the infinite regress problem). So how would one's interpretation be if one labeled both the outside and the inside view as being mere approximations?
     
  5. Dec 24, 2011 #4

    Hurkyl

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    And what's wrong with that?

    I find the "infinite regress problem" to be a silly thing. It's a perfectly good argument, but people draw the wrong (IMO) conclusion -- I use it to refute the unreasonable expectations I often see attached to words like "explain" and "understand".


    I agree that said mathematician could compute the inside view of the theory, but there is no way he can compute what a 'self-aware observer' would obtain.


    This is the important part of the logical notion of "interpretation" -- of semantics. A mathematical theory is pure syntax. Put crudely, it is a meaningless game played with meaningless symbols. We pair the theory with an interpretation -- a scheme for using the symbols of the theory to refer to something else. The point of science is that we set up interpretations where that "something else" is supposed to be elements of what is 'real'.


    Okay, that's not strictly true -- there is (what I understand to be) the mathematical universe hypothesis. If we assume that, the mathematician could compute what a 'self-aware observer' would obtain -- but ironically that answer would be entirely content free.
     
  6. Dec 25, 2011 #5
    The most fundamental problem science must address in the next decades is to clarify the nature of the relation between the physical world and our mathematical theories... Why do they work ?
    I doubt the explanation is purely mathematical... Nothing in the universe is self sufficient... And I hope we will not be stuck with wording or semantical notions like "interpretation" (In linguistics and semiotics, the symbols are paired with referents -objects -, not interpretations), for example... Their condition of possiblity is the absence of such an explanation...
    How to address the problem is a terra incognita right now...
     
  7. Dec 25, 2011 #6

    Ken G

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    In my view, the inside view is the only one we ever get. This is demonstrably true, actually. So the whole notion of an "outside view" (essentially the god perspective) is a complete scientific fiction. It can be believed in, like a religion, but science is not about any outside view, it is all about explaining the inside view, from the inside view, by inventing a notion of an outside view purely as a convenience. All of this is completely clear from how science works. Why it works is another question-- a question that is outside science.
     
  8. Dec 27, 2011 #7

    Ken G

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    But what would a theory look like that answered the question "why does this theory work?" Could not that same question be applied to that particular theory? I don't see that this is something that science does, it would require doing something other than science. So far, that "something" is philosophy, but it serves more to clarify the questions and their possible answers, than it does to provide unique answers.
     
  9. Dec 27, 2011 #8
    To the fiction of an "outside view" you add another fiction : the "inside view"... The outcome is a radical subjectivism... 20th century philosophy has debunked this kind of concepts... There is no "insides" and "outsides", only collapsing entities : a mathematically structured relation between subjects and objects...
    The task of the philosophy of science is to clarifiy this relation, not to endorse one side and forget the other... This is a fact : there is no subject, no thought, no science and social life without an outside world to structure our experience of it... The indivdualist bias (and its "psychologistical" consequence) of the american ethos is obvious in your conception... The brain, the subject and the individuals are not the alpha and the omega of our being in the world... They function in a much larger relational experience and we're not their prisoners... What I am telling to you is simple : there is no "center" to the scientific process : neither the subject nor the object...
    To think that we are by nature unable to analyze science conditions of possibility, that's the real religious statement... Ironically, it leads to the same conclusion made by 19th century objectivism... That the actual state of the art is the best we can do (I am not talking about the content of the theories but about their epistemological formalism), almost a universal limit... That's not the first time we here about such claims... For me, it's a reversed dogmatism : we are sure that we will never know... The nature of the link between mathematics and the world are not outside the realm of science but only of your conception of it... This is our margin of progress...
    The critical point is the encounter of different intelligent species...
     
    Last edited: Dec 27, 2011
  10. Dec 27, 2011 #9

    Ken G

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    I agree that an "inside view" can also be a fiction, it depends on how one characterizes it. All I mean by the term is the view that we get that is a product of how our minds work, and it is demonstrably true that this is the only view we'll ever get.
     
  11. Dec 27, 2011 #10
    And what I am telling you is that there is no such things as "mind products" without a correlative and ontologically distinct "reference frame"... An that is a fact...
     
  12. Dec 27, 2011 #11

    Ken G

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    I'm not sure we can say there is either mind products or reference frames, or any particular relationship between them that supercedes the "inside view", because these and all other concepts and words and ideas are all parts of our "inside view." That's what the inside view means, the view from our perspective, and all that comes with it, including the concept of a perspective and the concept of a mind. I'm not saying the inside view is a product of our minds, I'm saying that our minds are the same thing as the inside view. I am saying there is no such thing as a scientific argument that goes "the inside view emerges from X, Y, or Z." The inside view is the starting point, all must emerge from it or it is not coherent. You might actually be saying something similar, in terms of the artificiality of the distinctions between "inside" and "outside." I'm just using the words a little differently-- if the inside view is our view, then it's all the inside view, there is no view without us in it because we are talking about our view.
     
    Last edited: Dec 27, 2011
  13. Dec 29, 2011 #12
    What I am criticizing is exactly this view... It has the appearance of truth but only the appearence of it... The logical conclusion of what you said is there is no such things as gravity or atoms independently of our "mind products", for example... It is a radical subjectivism that undermines the very mission of science (which is to give us a consistent and testable insight on what is going on in the universe, not to stuck us with mathematical solipsisms) and the validity of its findings... To argue that science is a simple projection of mental concepts is an oversimplification...
    To justify your position, you'll have to prove that what we can see in our experiments and what we can model are wrong or just an illusion... You can't stay at this very basic level of who's producing the science while contesting its ontological claims... You can't get rid of the subject or the object : the scientific process is all about filling the gap... And there is no clear starting point as you think... Thought is not only a characteristic of manhood but also what opens our view on the universe that created us... The "mind" gets a "feedback" that chellenges its categories... Quantum mechanics is a "classical" example in this regard... Wether we will have a complete picture on the epiphany of the universe remains an open question... But we can't reasonably argue that science doesn't even adresses the question and it doesn't come up with some results...
    The critical issue in science is the progression from what we know to what we ignore yet... The relation between the subjects and the objects must be analyzed in that perspective...
     
    Last edited: Dec 29, 2011
  14. Dec 29, 2011 #13

    Ken G

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    I would say that it is perfectly demonstrable that there is no such thing as the word "gravity" or the word "atom" without us. There is also no such thing as a physics theory that invokes these concepts without us. I'm also saying that there is no way to test the value of any of these concepts without us, because we are the ones who do that testing, using our senses, our minds, and our judicial faculties. These are all absolutely incontrovertible facts. Now, anyone is certainly welcome to adopt a personal philosophy that gravity and atoms do exist outside of us, but that personal and subjective opinion certainly does not contradict any of the incontrovertible facts I just listed.
    On the contrary, the list of facts I just gave are a fairly complete description of exactly what science is. I never understand why people seem to need to replace what science actually is with some imagined version that it has never been, it is as though they don't think science would have any value if they just dealt with what it actually is. That is of course untrue-- science is what it is, and it does have value, and there is never any need to pretend it is something different. Yet if someone is unwilling to enter into that pretense, they get labeled silly things like a "radical subjectivist." That's hooey, not a single thing I said is the least bit subjective, indeed my entire goal is to remove subjectivity. The argument you are presenting is the one that is purely subjective. That doesn't make it wrong, it makes it undemonstrable, and believed out of choice rather than out of logical necessity.
    Who ever said any such thing? I certainly don't think science is simple, and if we are to call it a projection then we need to be able to say what it is projecting from and projecting to. I do see projective elements in science, but I wouldn't even begin to try and elucidate what is being projected from or projected to, so it would seem better to just stick to what we can demonstrate that science does, which is easy enough to do by watching scientists.
    Why on Earth would I need to prove that? None of that is the least bit important to what I am doing, which is simply pointing out the demonstrable facts about what science is, devoid of any subjective issues like what we choose to regard as right, wrong, or illusory. Science has nothing to do with those kinds of subjective labels, it simply has goals, and it meets those goals to various levels of success. Nothing absolutely right, nothing absolutely wrong, nothing absolutely illusory-- science needs none of those labels, which is a good thing because virtually every aspect of physics I know can be labeled any of those three things in various contexts.
    Your version of science has no clear starting point, and you think that argues you have a better version of science? I think it's rather important that science must have a clear starting point, that's the only way to know what we are doing. That's the problem with pretending science is something other than what it is-- we lose track of what we are actually doing, and afford the effort almost supernatural properties.
    Of course it comes up with "some results," it's obvious that it does and no one ever claimed otherwise. But we can certainly question, and should question, the usefulness of the concept of any such thing as "a complete picture", on the simple grounds that science has never been about that so should hardly be expected to suddenly become about that. The idea that the goal of science is to achieve a complete picture is exactly what I mean about the need to pretend that science is something other than what it is. Why do we need to pretend that?
     
  15. Dec 29, 2011 #14
    You don't understand what I have said... The only thing you can get in science is a progressing knowledge stemming from a structured and conscious relation between subjects and objects... It has no principial limits... The key issue is not the terms (subject and object) but the relation itself... Neither the subject nor the object are sufficient to themselves... Both are active in the relation... If you don't think so, you dont understand what an experiment and what a test are and you end up with intellectual monologues...
    Let the cosmologists of the PF know that gravity has no link with the formation of the solar system... It waited for our science to trigger retroactively the formation of the planet, animal life and subjects... That's the kind of statements you are implying... It's a pure denial of what science is...
     
    Last edited: Dec 29, 2011
  16. Dec 29, 2011 #15
    So how, using science, do we step outside of the conscious relation between subject and object in order for you to show that atoms or gravity exist independently of that conscious relation between subject and object?

    The scientific method requires a separation of subject and object. That separation gives us an apparent strong objectivity but turns to a weak objectivity at the quantum level. Can we be sure then that the strong objectivity within our macroscopic reality really is strong? Might it be the case that there is a purely subjective “whole” within which our reality emerges with the appearance of a subject and object separation? We can practice science because of the separation apparent within our reality, but outside of the “whole”, outside of mind and consciousness, that science is not applicable, apart from feeding philosophical enquiry.

    You can believe that the separation of subject and object is universal and you can believe that that separation gives science the potential to reach the ultimate reality. But that’s all you can do, you can’t turn to science to justify that belief. The only thing that can be done is to see science for what it is – the formulation and verification of mathematical predictive theories and models within our reality. To extrapolate those verified theories and models beyond our reality (beyond empirical reality, beyond the “whole”, beyond mind and consciousness) is to embark on a philosophical quest.

    Gravity does have a link with the formation of the solar system within empirical reality. Is empirical reality the same as mind independent reality? Does space and time exist as we perceive it within mind independent reality? Does the solar system exist within mind independent reality? Who knows? My philosophical perspective says it doesn’t, I don’t think there is a historical time line within mind independent reality, I think we extrapolate back within our reality and legitimately create a historical time line of empirical reality – a reality involving minds. You philosophically will completely reject that view, but it doesn’t matter what either of us think, it has nothing to do with what science is. The scientific method produces scientific truths within the remit of the means by which science is practiced. That remit demands the separation of subject and object, but nowhere does science prove that separation as being a universal truth.
     
  17. Dec 30, 2011 #16
    I have never said that we can get to an "objective truth" without the usage of our "minds"... The forclosure of our cognitive skills is a myth or an illusion though... Although genetically determined, they only develop with getting in contact with the world around us... It's a contingent process... And it's a neurological fact... The subjectivist and the objectivist understanding of science are both wrong...
    The whole reasoning of Ken depends on three basic assumptions : (1) that the "mind" gets only what it had already projected and, consequently, (2) that our brains and senses are unable by nature to reveal some truth about the world, since they can only collect their own inner "concepts"... (3) Which means that our scientific theories are self referent and does not disclose anything on the studied objects... That's three phlosophical statements, almost religious, not scientific truths...
    This "découpage" of the scientific process is wrong... It doesn't start with an absolute subject, there's a whole ontological structure before and after it... Why a natural being should be forbidden to make ontological claims about nature ? Because we have decided it ? It is not reasonable... Once led to it's logical and concrete consequence, it is nonsensical...
     
    Last edited: Dec 30, 2011
  18. Dec 30, 2011 #17
    Well all I’m saying is that the object does get studied by the mind in terms of an observer with cognitive skills in one corner and the object in the other corner separated by space and acted out in time. The knowledge so gained is a scientific truth of the object in terms of its existence within empirical reality. Empirical reality is our reality and within it, observers, minds, consciousness, space, time and objects exist as we experience them.

    I’m not sure that I would describe Ken G as a radical idealist in the manner you suggest, but in any event, whether one adopts radical idealism or naive realism, both those two extremes have no bearing on the scientific method. The scientific method simply takes as a default position the separation of the subject and object. Even at the quantum level it does that in spite of the clear observer dependence – it succeeds because of intersubjective agreement.

    Within that default position, scientific truths emerge, but they are truths only in terms of empirical reality. That would be the case for a radical idealist or the naive realist; both those stances are philosophical in nature and have no connection with scientific truth.

    So I’m afraid I don’t understand why you think science is being shut out by philosophical stances of any persuasion (which include the philosophical stances you describe as subjectivist or objectivist), the scientific method carries on regardless and will continue to provide powerful scientific truths, “truths” however that are applicable only to empirical reality – our reality.

    Attempts to extrapolate those scientific truths as “truths” to philosophical stances are in my opinion misguided – I’m not saying you are trying to do that, I’m just not sure. There is nothing wrong in making use of those scientific truths as a means of feeding one’s own philosophical perspective, but they are no longer truths in that context, the “truth” is a truth that belongs only to empirical reality – the only reality we can ever know. We have no means in which to adopt a God’s eye view and examine our reality detached from our place within it and thus decide if our scientific truths have universal validity within a reality that is entirely independent of our minds.
     
  19. Dec 30, 2011 #18

    Ken G

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    I can basically agree with all of that, which is why none of it contradicts in the least anything I have claimed above. Why have you framed those statements as some kind of refutation of the simple fact that science is how we try to understand and describe an environment that includes us, and there is no need at all to pretend it is anything else? In particular, there is no need at all to pretend that science does not fundamentally have to do with us, how we think and perceive, and what goals we have set out for science. Science quite clearly involves all those things, they are central to science, so I see no need to pretend otherwise.
    No, nothing I have said implies anything like that. What I said is what I repeated just above. There is no need to pretend that science does not involve us, or that science would exist without is, in order to use science to understand things that make sense to us to imagine happened before there was us. There just isn't, but for some reason people always want to pretend there is. Did those things really happen? Well, we can only give meaning to the terms "really happened" by going with what makes sense to us, that's the point.
     
  20. Dec 31, 2011 #19
    Obviously, it's a dialogue between deafs as french people puts it (dialogue de sourds)... Does quantum mechanics make sense to us... ? I don't think so... The goal of science is not to end up with "meanings", but to know the mechanisms that produced us...
     
  21. Dec 31, 2011 #20
    I have never said what you think that I have said...
     
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