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How does physics allow for the existence of observers?

  1. Aug 1, 2004 #1
    How does physics allow for the existence of observers?
  2. jcsd
  3. Aug 1, 2004 #2
    Point symmetry, and observing the perimeter. I think off hand. :redface:
  4. Aug 1, 2004 #3


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    What the heck are you asking? Observers exist. Physics doesn't allow or disallow this. It only describes the interactions that take place.
  5. Aug 1, 2004 #4
    how does physics allow for interaction between particles you ask? that's a pretty broad question...
  6. Aug 1, 2004 #5
    Relativistically of course.
  7. Aug 1, 2004 #6
    Loren are you a psychologist? I always get the feeling by your questions, your are studying, not so much the answer but who answers and how.

    Through photon exchange.
    Last edited: Aug 1, 2004
  8. Aug 1, 2004 #7
    loseyourname, you may well have said that observers do not interact with their physical environment. I suppose you would disagree with the Anthropic principle. Are observers then metaphysical entities?

    balkan, for instance, one might state that physics requires the presence of observers. Does physics itself explain what observers are, though?

    wuliheron, could also observer and object exist as quantum mechanical complements?

    Rader, I often couch my statements in the form of questions. Perhaps that seems psychoanalytical. I do have some background in psychology, though. I tend to ask and stand back, in part because I do not respond as quickly as others (especially in philosophy).
  9. Aug 1, 2004 #8


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    You're losing me, Loren. I just said that physics explains the interaction between observer and environment and you think I may well have said that observers do not interact with their environment? How'd you make that leap?
  10. Aug 1, 2004 #9
    one might state that, yes. One might state that the queen of britain is made of french cheese, but that doesn't give it any relevance or validity...
    what have you got going for it?
  11. Aug 1, 2004 #10
    Please excuse my froginess, lyn. Your present translation I agree with for the most part. You may wish to review your exact original wording that I responded to:

    How might describing an interaction necessarily allow for a separate observer and object? Also, do you believe that the Anthropic principle could give a physical justification for the presence of observers?

    balkan, I inferred from you, as from loseyourname, that interaction is essential to the identity of observers, and may be the link to their physicality. If observers are not themselves physical, how can one explain apparent direct interactions between them?
  12. Aug 2, 2004 #11
    why wouldn't observers be physical? and why on earth should the universe neccessarily have observers in order to exist... nobody would know it existed, but what has that got to do with anything?
    that's like saying bacteria didn't exist untill we discovered them...
  13. Aug 2, 2004 #12
    ...or as Einstein mused to the quantum mechanics, that the Moon didn't exist unless we were looking at it.

    If not unphysical, observers may well follow different physical laws relative to each other than to their objects.
  14. Aug 2, 2004 #13
    You make a good point Loren about Einstein and quantum mechanics. Either quantum mechanics points to the metaphysical or we live with Alice in Wonderland. We either live in an observer based reality where nothing exists until observed or we live in many-worlds and everytime a decision is made a split occurs.

    With many-worlds you have to allow for quantum immortality for instance:

    Say I'm out shopping and I either decide to stop shopping and cross the street to my car or I continue shopping and walk into the next shop. In one world I cross the street to my car and I get hit by a truck and die yet I'm still alive and shopping in the other world. Quantum immortality doesn't violate quantum physics.

    Obviously some have trouble with an obsever in physics because of the metaphysical implications. One, they can't really define an observer and two they don't know why the observer causes the wave function to collapse. This is why some try to minimize the role of the observer or eliminate it with no-collapse theories, especially in quantum cosmology.

    Like I said in an earlier post I think many-histories fits better than many-worlds, along with the role of the observer.

  15. Aug 2, 2004 #14
    Yes, but even then they would be relative. Am I the observer, or the observed? It really just depends upon the context. Since no one has ever proven the existence of any kind of logic behind quantum mechanics, the only demonstrably meaningful answer we can give is a relativistic one.
    Last edited: Aug 2, 2004
  16. Aug 3, 2004 #15
    harold, i think you have quite confused yourself with those quantum mechanics statements...
    the electron does not have to be observed in order to do anything, but you cannot be sure of it's location untill you check it out due to uncertainty... it surely does exist before being observed, but you just cannot be sure about where it is, so the "nothing exist untill observed" is quite false...

    the many worlds idea is just a theory, but it is definitely not a neccessity. there are plenty of other theories to go around.

    and please stop that "THANK YOU LORD JESUS" thing. i don't go around posting "GOD DOESN'T EXIST!" or "GOD EXIST ONLY FOR YOUR PSYCHOLOGICAL COMFORT!" do i?
    please show the same courtesy.
  17. Aug 3, 2004 #16
    Please do not worry we know you are not Harold. :surprise:
  18. Aug 3, 2004 #17
    i know... i have more backbone than that....

  19. Aug 3, 2004 #18
    hehe... :wink:
  20. Aug 3, 2004 #19
    This doesn't agree with anything I have ever read on quantum physics. This seems to imply that the problem we face with quantum physics is purely a problem of what we can know (epistomology) and not a statement about reality itself. Here's a simple quote from a website that while it doesn't say "nothing exists", it clearly states that the ontology of subatomic particles changes as a result of an observation. Some people have written that it isn't really inaccurate to say that subatomic particles don't really exist anywhere or anywhen until observed.

    "An unobserved quantum entity is said to exist in a "coherent superposition" of all the possible "states" permitted by its "wave function." But as soon as an observer makes a measurement capable of distinguishing between these states the wave function "collapses", and the entity is forced into a single state."

  21. Aug 3, 2004 #20


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    There is an interpretaion of quantum mechanics (caricatured as "Shut up and calculate") that claims QM simply doesn't tell us what the particle is, or does, by itself. What QM enables us to do is to calculate the results of our experiments on the particle, and to do that we have to build information about the experiment into the calculating math. This is the "preparation" that Bohr laid so much stress on.

    So in this interpretation the coherent superposition you mention is a mathematical stand-in that is needed for our calculation, but should not be confused with a statement about the nature of the particle. So for believers in this, QM is an epistomological theory, as you said.

    But I emphasize this is only one interpetation. Many physicists are eager to reify the coherent superposition. These are the ones who make ontological assertions about the state of the particle and its properties between experiments.
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