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QM in the ancient past.

  1. Sep 2, 2007 #1
    If the observer effect changes the results of measurements in QM, would the rules be different if there were no observers? Like on earth a billion years ago, there was nothing like an active mind around, just microbes. You couldn't count them as effecting QM could you?
    Likewise, if you posit life having been around the galaxy billions of years ago and therefore a universe with active minds to interfere with QM, what about the time 13 billion years ago, when there were hardly stars around, just the plasma clouds condensing and not much even in the way of organic material, forget life. So there had to have been a time when the entire universe was totally mindless. So in that early universe, were the rules different than they would be now as far as QM goes? Does a mindless universe and a universe with minds operate any differently?
  2. jcsd
  3. Sep 3, 2007 #2
    As soon as one mind make an observation it determined the present, the past and the future for the entire history of the universe.
  4. Sep 3, 2007 #3
    who ever said anything about minds??? all that i've ever seen is:

    \Psi = \sum_i \alpha_i \phi_i

    where [tex]\Psi[/tex] is an eigenstate of the Hamiltonian and [tex]\phi_i[/tex] are the eigenstates of some observable.
  5. Sep 3, 2007 #4
    Sonhouse: if you want to understand QM, learn it from a textbook. No other sources are acceptable.
  6. Sep 3, 2007 #5
    absolutely it is a good question.but please remember what is the mean of observation?the nature of observation is the interaction between photon(electron and so forth)and matter.and this process is independent of the observer.i think you may want to ask how is the QM system evolution without any observer,instead.if you want to know the details of this question,please see the bohmian mechanics that is one of the interpretations of QM.also,you can see the many-world interpretation which is the other way to answer your question.BTW,if you want to know the relationship of mind and matter,there is an article in attachment for you

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  7. Sep 3, 2007 #6


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    Also a textbook that is used in universites as course litterature or equivalient.

    As unica said, a measurement is done by nature. Interaction with matter and so on, later we look in a dector or similar so see what happened. And our eyes are detectors too if you remember your biology/anatomy. As long as there is matter, observation is done, there is no need for an intelligent interprenatior for the wave function to collapse.
  8. Sep 3, 2007 #7
    Does nature calculate probabilities? Or is it just humans who care about how likely something is? Collapse of the wave function... when does it matter if humans are not calculating probabilities?
  9. Sep 3, 2007 #8
    So in another thread, I made this post:
    I think this question applies here (and this is a much more recent thread, so maybe it will get replies?) -- is any interaction considered 'detection' and if so, how does that affect the delayed choice quantum eraser experiments?

    By the way, this is the experiment I refer to: http://arxiv.org/abs/quant-ph/9903047
  10. Sep 3, 2007 #9
    I call this idea the "Quantum Dreamtime Argument"- QM states that the less information about the environment is causally connected to an observer's structure- the less resolved are those elements of the quantum state of the local system- so before humans things had to be more blurry- but how blurry? it could be very subtle or quite dramatic- we will find out when computers are powerful enough to run simulations of the laws of physics to detail equivalent to physcial reality-
  11. Sep 3, 2007 #10


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    Mike2: Is our mind anything else than atoms and electron impluses? Does not probibalistical events happen unless humans measure them?
  12. Sep 4, 2007 #11
    Heisenberg was a pantheist, and believed in consensual reality. Many other famous physicists have similar views. The original idea was that everything existed in a quantum superposition until observed.
  13. Sep 4, 2007 #12


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    yes, but what do we mean by "observed" ? We must first define that, and also we must define the nature and essens of the human mind and reson.
  14. Sep 4, 2007 #13
    In the case of consensual reality, as Allan Watts put it, "God is playing Peek-A-Boo."

    To observe something is to become aware of it.
  15. Sep 5, 2007 #14


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    Yes but to be aware of something, there must exist non-matter parts in our mind. Otherwise there is no difference between our eyes and mind measuring and if a rock would have interact with an electron or so on.
  16. Sep 5, 2007 #15
    If one thinks of past events in terms of present perspective, indeed our collapsing wavefunctions now determine measurements attributable to former times. Yesterday may be seen as projected upon today. How else could we interpret history? The Many Worlds view of quantum mechanics proposes a lineage for us to retrace, in this moment, back to the first instance of physical interaction.
  17. Sep 6, 2007 #16
    Actually, I don't know the details of Heisenberg's personal spirituality.

    However, consensual reality is the idea that every consciousness agrees on some level to what reality will be and, thereby, creates reality. Note that this does not mean consciousness must be made of something other than matter/energy. In fact, it is a holistic viewpoint that says matter and energy cannot be separated. Consciousness can therefore be viewed as an emergent property, rather than something particularly non-material.

    For example, Rodger Penrose suggested that the human brain may physically be influenced by quantum events and vice versa. John Wheeler has suggested that on a quantum level information may be more important than matter or energy. Etc.
    Last edited: Sep 6, 2007
  18. Feb 12, 2008 #17
    "Actually, I don't know the details of Heisenberg's personal spirituality."

    In his book History of philosophy it is quite clear that he is an athiest.
  19. Feb 12, 2008 #18
    For a discussion of Wheelers ideas, "it from bit" see:

    I can't vouch as to its accuracy, as Saffatti seems to have some rather radical ideas.


    Jack Sarfatti (born September 14, 1939) is an American theoretical physicist

    Also there is this article :

    If were not looking does the universe exist?

    Linde believes that Wheeler's intuition of the participatory nature of reality is probably right. But he differs with Wheeler on one crucial point. Linde believes that conscious observers are an essential component of the universe and cannot be replaced by inanimate objects.

    "The universe and the observer exist as a pair," Linde says. "You can say that the universe is there only when there is an observer who can say, Yes, I see the universe there. These small words— it looks like it was here— for practical purposes it may not matter much, but for me as a human being, I do not know any sense in which I could claim that the universe is here in the absence of observers. We are together, the universe and us. The moment you say that the universe exists without any observers, I cannot make any sense out of that. I cannot imagine a consistent theory of everything that ignores consciousness. A recording device cannot play the role of an observer, because who will read what is written on this recording device? In order for us to see that something happens, and say to one another that something happens, you need to have a universe, you need to have a recording device, and you need to have us. It's not enough for the information to be stored somewhere, completely inaccessible to anybody. It's necessary for somebody to look at it. You need an observer who looks at the universe. In the absence of observers, our universe is dead."

    Last edited by a moderator: Feb 12, 2008
  20. Feb 12, 2008 #19
    The OP's post is making the assumption of what Wikipedia calls the “http://en.wikipedia.org/wiki/Consciousness_causes_collapse" [Broken]” scenario is something that Schrödinger came up with to make fun of this kind of thinking, not to endorse it.
    Last edited by a moderator: May 3, 2017
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