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Paradox of the Universe - Physics or Voodoo Philosophy?

  1. Mar 5, 2010 #1
    I wrote a response in a thread entitled "What is the single most important thing for life to exist in the universe?" . I thought about it some more and I am wondering if this paradox is scientifically sound or is it just crazy philosophers taking physics and making into voodoo science. I hope its OK to pose this question here. My statement:

    You have to understand the paradox of the universe. The universe can only exist if there are sentient beings (consciousness) able to observe it. If there are no sentient beings, then the universe exists as a wave, without any form or structure. Only after sentient beings observe the universe does the wave collapse into the beautiful firmament of stars, planets, galaxies, quasars, etc. Thus, the single most important thing for life to exist is a universe that provides the right quantum laws that allow for sentient beings to evolve. That is, the gravitation strength is this and the strong force is that and the weak force is this and the electromagnetic force is that. If any of the four forces deviate by a slight bit, then the conditions of the quantum laws will not be correct for life to exist. It is the precise tuning of our laws of quantum mechanics that is the most important factor to create sentient life.

    There may be parallel universes that exists as only a wave function because those universes did not provide the correct quantum laws for sentient beings to evolve. Those universes are dead in the sense that they are unable to form a firmament of astronomical bodies including a sun and a planet with beautiful water and sky. There is no such thing as a "barren" cold universe unless somehow we observe it through a black hole (impossible to do). Until then, its only a wave. There are probably an infinite number of universes in the form of a wave waiting for sentient beings to observe them so they can collapse into a world of particles and matter.
  2. jcsd
  3. Mar 5, 2010 #2
    Even proponents of Copenhagen Interpretation do not believe that it is consciousness that causes collapse. But there is a new trend from 199x: there is no collapse. Collapse is replaced with Quantum Decoherence, measurement problem is solved, no consicous beings are required.
  4. Mar 5, 2010 #3
    The problem i have with the paradox is how can the universe pass through the different phases of its own evolution if it is not being observed? Does that mean that the wave function itself is evolving? I like the idea of replacing sentient with Quantum Decoherence. But, i must ask, what the heck is Quantum Decoherence? I'll do some reading and start with wiki.

    Last edited: Mar 5, 2010
  5. Mar 5, 2010 #4
    1. Yes, the wiki article is a good start
    2. Wavefunction itself is evolving
    3. No observations of conscious beings is required for any processes to happen.
  6. Mar 5, 2010 #5
    The wikipedia article on Decoherence says that it doesn't attempt to solve the measurement problem, which makes sense given its definition there. Is that wrong?
  7. Mar 6, 2010 #6
    Not true. There's no reason that an observer has to be sentient to collapse the quantum wave function. For the purposes of quantum mechanics, a non sentient Geiger counter works perfectly well to collapse a wave function.

    The term "observer" is a bad term to use. The right word is "detector."
  8. Mar 6, 2010 #7
    Congratulations! You are on the next level :)
    So yes, decoherence shows that no collapse is needed. It explains why we don't see macroscopic objects in superposition, but it does not explain why we observer only one outcome.

    It rules out collapse interpretations (Copenhagen, TI) but leaves a choice between different non-collapse interpretations (MWI, BM). These interpretations explain defferently why ww observe only 1 outcome.
    Last edited: Mar 6, 2010
  9. Mar 6, 2010 #8
    Thank you, i figured the MWI is the Many Worlds Interpretation, and i didn't get what BM was, I have a question on this matter; Is Decoherence widely accepted among physicists?
  10. Mar 6, 2010 #9
    Copenhagen Int uses the demagogy, switching back and forth between 2 close but different views.

    When being asked: “How Wavefunction can collapse instantly?” copenhagens reply “Wavefunction is just our knowledge about the system.
    When being asked: “Do we need conscious beings for the wavefunction collapse?” they say: “No, the measurement device is required for the collapse, not humans”

    Copenhagen Int was the very first and it was very useful, but in the era of Quantum Computers, when there is no longer a sharp line between Macro and Micro worlds it does more harm then good.
  11. Mar 6, 2010 #10
    BM=Bohmian Mechanics.
    Decoherence is mathematical thing, so it is difficult to reject that 2+2=4 :)
  12. Mar 6, 2010 #11
    The problem with all of these interpretations of quantum mechanics is that they lead to the same experimental outcome.

    If they didn't, we could just do an experiment and see what works. So by "accepted" you mean that someone using the concept of decoherence to do a calculation, you don't have any choice but to accept the calculation, however someone that doesn't accept the ideas as a philosophical explanation for what is really going on will take the paper, accept the calculations and results, and then mentally rewrite the paper to fit what they think is "really" going on.

    What you can do is to take a paper that is written from a given interpretation that then "translate" it into any other interpretation you want. If you couldn't do that, then you just do the experiment and see what happens.
  13. Mar 6, 2010 #12
    No, the reply from the Cophenhagen interpretation is "just do the math."

    The problem is that if you require human beings to do the collapse, then if you get yourself in a Schodinger cat situation you end up with wavefunctions that are not calculable, and hence you have no theory.

    Also, I was at a talk by Bryce DeWitt, a long, long time ago, in which he was arguing that the "magic thing" that causes a wavefunction to collapse is an interaction with any massive object. It was a weird talk, because I started talking notes, and as he was talking, what he was saying seemed so painfully obvious I stopped taking notes, but I can't remember the argument now.
  14. Mar 6, 2010 #13

    Thank you both for helping me with this topic.
  15. Mar 6, 2010 #14
    No, it is "Shut up and calculate" aka macroscopic realism
  16. Mar 9, 2010 #15
    I thought that it was impossible to separate conscious observer from any measurement, and thus decoherence theory will never be able to be proven beyond all doubt? How do you know if it's the detector entangling with the wavefunction or if it's the measurer's consciousness endearing a non-local wavefunction collapse over time? How do you separate the two in any measurement?

    Oh wait, I just read another of your posts. Are you sure this totally, 100% debunks the "consciousness causes collapse" possibility, or is this just your stance. Couldn't there be other ways at looking at the S Cat paradox where you don't run into the problem you stated?
    Last edited: Mar 9, 2010
  17. Mar 9, 2010 #16
    Moreover, if you read this experiment:


    The conclusions, seen in bullet points 1/2/3/4 near the bottom of the page purport to debunk most ways of looking at decoherence theory, along with many other interpretations, and seem to support the consciousness causes collapse interpretation.

    Although I'm not sure of the veracity of the source.

    What are we to make of this? Has this line of experimentation been carried out anywhere else?
  18. Mar 10, 2010 #17
    I don't see any new experiments decribed in this article.
    And I don't see how it supports 'consciousness causes collapse'
  19. Mar 10, 2010 #18
    Supports was a bad word, more like 'leaves the door open for'. So wait, are you saying the Conclusions presented in 1/2/3/4 have all been found to be true before? (I'm not a physicist, but I thought this wasn't the case). If so, why is decoherence theory so popular, and why do proponents of decoherence theory claim that the measuring instrument endears collapse? Also, why is the consciousness causes collapse interpretation so unpopular given these results? The conclusions seem to imply that either:
    The data of the which path information is entangling with the wavefunction
    A conscious measurer is required to collapse the wavefunction
  20. Mar 10, 2010 #19
    1. Quantum Decoherence is not a physical theory, it is rather a mathematical instument, a mere consequence of QM. This is why it is accepted ("popular") - because one can't deny Decoherence without denying QM at whole.

    2. You look confused:
    "why do proponents of decoherence theory claim that the measuring instrument endears collapse" is not true: Decoherence denies the very existence of the collapse. THere is no collapse at all!

    3. It gives an answer to "why is the consciousness causes collapse interpretation so unpopular given these results" - because there is no collapse.
  21. Mar 10, 2010 #20
    I see. It looks like more research is needed on my part. Thx for clearing that up.

    I'm still a tad confused though, is decoherence compatible with other interpretations, or is it a mutually exclusive interpretation in itself?
  22. Mar 10, 2010 #21
    Decoherence is a consequence of QM.
    So it is compatible in that sense with the other Interpretation.

    However, in Copenhagen Int (and other collapse Int) the situation becames confusing: there are 2 things to explain why the world we see is classical: old Collapse and new Decoherence.

    For that reason I believe after the discovery of Decoherence the status of "Collpase" in the same as status of "Light Either" so Copenhagen is interesting only in historical aspect.
  23. Mar 10, 2010 #22
    So, are you saying that if Decoherence Theory was proven beyond any doubt, all collapse theories would subsequently be proven to be deficient, as decoherence theory states that no collapse is actually happening?
  24. Mar 10, 2010 #23
    Decoherence is widely accepted and is intensively studied. Again, you can't deny QD without denying QM. So since 199x collapse theories makes no sense (of course, collapse can be used in a form of "rule of thumb" when we don't care about what is actually happening and our measurement devices are big and simple enough)

    And of course, diehard proponents of Copenhagen Int will not agree with it, but I made an experiment on this forum about 1y ago, trying to find proponents of Copenhagen Int on this forum. And I had failed :) There was only one defender of CI about 1.5y ago (jambaugh) but I believe he is avoiding any interpretations wars now.

    If you know any proponents of CI, it would be interesting to discuss with them their view.
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