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B Why did famous people think consciousness causes collapse?

  1. Feb 5, 2017 #1

    also schrodinger believed it, and maybe bohr too?

    this is such a stupid concept, it's obviously false. but clearly i must be missing out on something, people like them aren't gonna believe in things that's "obviously false".

    has anyone sat down in a dark room with the electron double slit set up, and concentrated his consciousness on the electron beam and see if it did anything?

    also i was reading this


    can someone explain what the quote means? i personally realism is obviously correct, the universe works just fine when we aren't looking at it. why is this consciousness thing even a topic? what made people believe?
  2. jcsd
  3. Feb 5, 2017 #2
    On a somewhat broader note. My late father - A theoretical physicist (graduate studies at advanced institute Princeton) who later switched fields to the philosophy of science (google his last book published just before his death at age 89: "quantum theory: a philosophers overview") - always used to decry physicists who sorely lacked philosophical depth. And a real pet peeve of his was ignorance around the very real problem of qualia, consciousness, and first person phenomenology. So even if your a Denette or Churchland aligned Materialist, there's no denying the lack of triviality of the current debate in the philosophy of mind around the place - or non place - of consciousness in the fabric of reality. Anyone interested should get hold of a book like "The concisous mind" or "the character of consciousness" by David Chalmers and give their intellect a useful workout
    Last edited: Feb 5, 2017
  4. Feb 5, 2017 #3
    I like this quote from Bohr:

    "In view of the influence of the mechanical conception of nature on philosophical thinking, it is understandable that one has sometimes seen in the notion of complementarity a reference to the subjective observer, incompatible with the objectivity of scientific description. Of course, in every field of experience we must retain a sharp distinction between the observer and the content of the observations, but we must realize that the discovery of the quantum of action has thrown new light on the very foundation of the description of nature and revealed hitherto unnoticed presuppositions to the rational use of the concepts on which the communication of experience rests." *

    * Niels Bohr: Atomic Physics And Human Knowledge, pg. 90-91
  5. Feb 5, 2017 #4
    Joseph, why do u think im siding with Denett? I'm converting to property dualism recently. But even so many years ago when I was a substance dualist and read about consciousness cause collapse, i thought it was completely nonsense. The universe gets along just fine when we aren't looking at it, a tree falling in the woods does make a noise.

    I hold that everything excluding consciousness can be explained in reductionist/materialist terms, believed this even when I was a substance dualist.

    I do not in any way deny the existence of consciousness/qualia, but i think its nonsense to think that consciousness can influence reality (other than controlling our own limbs).

    I will take a look at the books u recommended. Thanks.
  6. Feb 5, 2017 #5


    Staff: Mentor

    It dates back to Von-Neumann - Mathematical Foundations of QM - a very famous early book on QM for many reasons.

    He did the analysis that showed the quantum classical cut can be placed anywhere - you will find the proof in the above book.

    Now he argued as follows - you can trace an observation back to the person that observes it without finding any place different - except the consciousness of the observer. So that's where he placed it.

    It was excusable at the time, and we have no less a personage than one of the greatest mathematicians and polymaths of all time saying it, all with impeccable math. Even so it only ever caught on with a few people because it really is weird. One of those people was the great mathematical physicist Wigner. Bohr, Heisenberg etc never adhered to it. Dirac as usual believed the math was the story - of all the early pioneers from the modern vantage he comes of the best - pretty faultless really (close but not completely, without going into details). Even Einstein admired him keeping a copy of his beautiful text with him at all times. That's another myth BTW that Einstein didn't understand QM - he understood it VERY well even putting forth his own interpretation - the Ensemble interpretation.

    Well Von-Neumann died early, but Wigner was around when the flaw in Von-Neumann's reasoning was found. There is a place that's different - just after decoherence. When reading some early papers about it by Zeth he did 180% about face and realised you simply place the cut after decoherence - no consciousness required. He then believed in real collapse type interpretations such as GRW but that's a whole new story. That's the error Von-Neumann made - there is a place that's different and the logical place to put it. Its now a very backward (though still valid) interpretation. The reason is the same as most people rejecting solipsism - intuitively its just too silly - you cant disprove it - but why bother?

    Last edited: Feb 5, 2017
  7. Feb 5, 2017 #6
    Interesting. So did Wigner corrected the error or did he promote Von-Neumann incorrect assumptions?

    But then since Von-Neumann cut can be place anyway. Is there a more solid refutation of his idea (or implication of his idea) that consciousness collapses the wave function?
  8. Feb 5, 2017 #7


    Staff: Mentor

    Yes - he wrote about it - but of course was not the only one to notice it.

    Of course not. It didn't disprove it. Consciousness causes collapse is still a perfectly valid interpretation and no interpretation is better or worse than any other. Its just one most people find overly weird and unnecessarily complicated.

    The issue on this forum is the people that believe it must be true without understanding its background and its not necessary at all.

    The OP is to be congratulated - he asked the question rather than saying - its true, obviously wrong etc etc. What he did is the correct way to approach physics. There is even a very good textbook on how our current view of QFT came about that analyses just what was needed for progress:

    His conclusion is the same as mine - progress happens when you ask the right questions. Learning as well.

    Last edited by a moderator: May 8, 2017
  9. Feb 5, 2017 #8
    Yes, though 'you cant disprove it'. seems to be an acceptable standard for a lot of people.
  10. Feb 5, 2017 #9


    Staff: Mentor

    Feynman would turn in his grave.

    While we don't discuss philosophy here, there are all sorts of views about its usefulness.

    I think Wienberg presents most physicists modern view:

    It's mine as well

    But there is no right or wrong here - its just something this forum doesn't discuss.

  11. Feb 5, 2017 #10
    I thought the decoherence formalism already refuted the idea consciousness causes collapse.. how could it still be a valid interpretation? Are they not in conflict? but then decoherence was proven by the c60 molecular experiment... so how could consciousness causes collapse still be valid??

  12. Feb 5, 2017 #11
    No, decoherence does not refute any interpretation.
  13. Feb 5, 2017 #12


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    Staff: Mentor

    Decoherence explains why we always observe macroscopically reasonable results and never weird things like Schrodinger's both-dead-and-alive cat. But that's not enough to solve the measurement problem and preclude a consciousness-causes-collapse explanation. Compare the following explanations:
    1) The quantum system consisting of Schrodinger's cat, the vial of cyanide, a detector, and a radioactive atom evolves according to Schrodinger's equation into a superposition of dead cat and live cat. We observe it, and that somehow causes it to collapse into a dead cat or a live cat.
    2) The quantum system consisting of Schrodinger's cat, the vial of cyanide, a detector, and a radioactive atom evolves according to Schrodinger's equation; decoherence means that this evolution will lead to the state "the cat is either alive or dead but not both at once". Then somehow this state turns into exactly one of those two possible outcomes. (Or both, if you subscribe to MWI, but that brings in a different set of problems).

    Both explanations work and are consistent with any imaginable experiment, and both require this magic "somehow".
    Last edited: Feb 5, 2017
  14. Feb 6, 2017 #13
    Can you please enumerate atomic processes (like protons or neutrons or strong force, etc.) where there is a similar decoherence into dead cat and live cat instead of dead/live cat inside the atoms or molecules? Also we are not inside atoms and observing any of them, so this proves consciousness is not involved in the collapse:) But then inside atoms.. is there a dead cat or live cat equivalent in any of the particles or systems?

  15. Feb 6, 2017 #14


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    By Bell theorem, realism leads to non-locality. For some reason, many people don't like non-locality. That's why they consider non-realism and the role of consciousness
  16. Feb 6, 2017 #15


    Staff: Mentor

    Decoherence usually requires interaction with something macroscopic and an environment.

    Decoherence simply refutes Von-Neumann's argument. That's all. It in no way disproves or proves the involvement of consciousness.

  17. Feb 6, 2017 #16
    Here's how decoherence may disprove the involvement of consciousness. Pluto decoheres into position basis even before the first cell originated on earth. So why don't you or others say it refuted this consciousness cause collapse thing?
  18. Feb 6, 2017 #17
    Since when Pluto is a quantum object?
  19. Feb 6, 2017 #18
    I mean the different atoms and molecules making up Pluto. Without decoherence with CMBR, etc. and position basis chosen, Pluto won't have position.

    Remember decoherence isn't supposed to produce definite outcome. Yet before first cells on earth existed. Pluto also has outcome. So consciousness isn't required for collapse. (but I don't understand why Bill or Nugatory seems not to agree... what is wrong with my argument?)
  20. Feb 6, 2017 #19


    Staff: Mentor

    That's true.

    Never understood it myself.

    Some just never seem to accept personal reactions are just that. Yet you will get them to admit anything consistent with experimental evidence may be true - that's the essence of science.

    For the record I don't believe in it (ie non locality - I don't even believe the concept is relevant to correlated systems), but that means diddly squat. I know it, others haven't quite woken up to it.

  21. Feb 6, 2017 #20

    A. Neumaier

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    Since it was named Pluto. Every planet (or former planet) is a multiparticle system, hence describable by quantum mechanics. For big objects such as planets, the classical approximation is very good, though.
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