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Observation and Reality Question

  1. Apr 2, 2009 #1
    As I was reading some information on Quantum Mechanics, I came across the following statement:

    (http://www.thekeyboard.org.uk/Quantum mechanics.htm)

    From this, several questions arose, but I'll only share a few. If indeed nothing is real until it is observed, and something must exist outside the universe in order for it to exist, doesn't this lead to an infinite regress? Something must exist to observe that which observes our universe, something must then exist to observe what observes that which observes our universe and so on. If this is not the case, does it mean that this concept of observation and reality only applies in our universe?

    As for John Wheeler's take on the issue, doesn't postulating that the only reason the universe exists is that we are here to observe it pose an issue about how the universe began? If it only exists because we observe it, could it ever have been created considering we were created inside of it?

    I appreciate any feedback.
     
  2. jcsd
  3. Apr 2, 2009 #2
    You can think of the first as a simple interaction. Anton Zeilinger talks about "the two freedoms." Your freedom as the observer is to choose what characteristic of a quantum to make real (momentum, position, spin) by the manner in which you measure/observe the system. But nature has the freedom to give the answer it gives. You don't decide the direction of a quantum's spin by observing its spin, but you do decide that its spin will become what's "actual" about it.

    All you need for "observation" or "measurement" are two quanta interacting. It doesn't require a human observer or man-made measuring device. Wheeler's anthropic metaphysics refers to an assumed evolutionary end-point. The universe, he claimed, needs intelligent observers to provide it with feedback because no system can fully describe itself. Intelligent observers provide a kind of mirror. The universe keeps building a better mirror.

    Prior to the Big Bang the universe presumably "existed" as a singularity: it had no observers. So for us it has the unique distinction of having actualized itself without assistance. Maybe you can get away with that if you're a universe. It is kind of a leap of faith, admittedly. But then constructs like "infinite regress" may just be the human mind playing tricks: why assume it has to represent an objective feature of reality?
     
    Last edited: Apr 2, 2009
  4. Apr 2, 2009 #3
    For now I won't enter the discussion put on at the paragraph citation ending because it throws us out of physics and into psichology, which has theories about the ego constructing the universe etc.
    I think all of this interpretation of Copenhagen is somewhat disposable, the affirmation that that nothing is real until obseved is much more useful as a premisse or method than as an actual object of studies. I mean, this affirmation forces the scientist to observe methodically everything, the object exist on itself but to be equacioned it needs to be observed.
    Without this premisse I can picture a desperate scientist trying to explain everything at once, but admiting that what he hasn't studied doesn't exist, he can worry about advancing little by little into the non-observed and thus being able to "grant" existence to other things.
    If the purpose of the submitance is to question reality as a picture of the ego, I reccomend that the author read some psichology, psiquiatry of even neurology, because trying to get to it by physics is complicated, because it's not an introspective science, it is based mayinly on observance of external phenoms.
     
  5. Apr 3, 2009 #4

    Fra

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    Some short personal philosophical comments.

    About the observational ideal and the origin. Then the origin of the universe, is unified with the origin of observers. Thus, a model of evolving observers of increasing complexity could effectively described the evolution of the _observed universe_.

    This does lead to an evolution (which you can call regress if you like), but then again, recall Einsteins first objection to his own equation of GR: "Does this suggest un unstable and evolving universe?" which bothered him and caused hime to put in the cosmological constant to try to find a fixed universe, only to later realised that the universe actually IS evolving (expanding). What he thought of as a problem, was instead a deep prediction of the universe.

    Similarly, how about if this evolution "apparent instability" of observers and observes, that you see as a "problem of regress" is in fact a correct description of nature? Time is running... things change, the sun is burning hydrogen... I dont' understand, what is so inappropriate about a little regress? After all, the world we observer do change, every day.

    Another sensible explanation in it doesn't exist if we don't oberver it, is if we not that obsevation means interaction, and something that isn't observed in any way, is simply not interacting with us, and then, in what sense would it make sense to say that it exists?

    However, it could be that one day something novel, will reach us and start interacting, and then we "discover it". One might argue that it existed before that, but that view has various problems rooted in realism. There is a rational basis for using that abstraction that information doesn't exists until you have it.

    The two problems here, the non-conservation of information, and the seemingly evolving or recursive nature of reality, mate well IMHO.

    /Fredrik
     
  6. Apr 3, 2009 #5
    just play a joke
    if in china ,you have the idea that Reality is depending on the observation ,you will be blamed by many people .Because the Marxism believes that the world exists outside us and independently of us,people who talk about the GOD and religions will be thought as stupid
     
  7. Apr 4, 2009 #6
    Like Gabrielh,I too have difficulty accepting the Copenhagen assertion that nothing exists until it is observed or measured;this view only leads to absurdities.The magnetic moment of the electron must have had its present value before there were any humans to measure it,otherwise we wouldn't be here.Similarly,the special resonance state of the carbon nucleus,predicted by Fred Hoyle,and subsequently confirmed must have always existed before its confirmation,otherwise we would not have any heavier elements beyond carbon.
    Contrary to the Copenhagen view,i believe that a quantum system can exist in a definite state,albeit a statistical ensemble,and nothing "collapses " when we make a measurement.
    We simply find out what the statistical outcome of the system is.If you like, "the collapse of the wave function"occurs in our brain when we (or somebody else)changes from a state of "don't know" to "do know".
    I think a lot of the replies to Gabrielh's original question strayed rather from hte point
     
  8. Apr 11, 2009 #7
    Heisenberg answers the OP with:

    "What we observe is not nature itself, but nature exposed to our method of questioning."


    Given the state of our knowledge, I'd say this is the best answer without straying too much into speculation.
     
  9. Apr 12, 2009 #8

    baywax

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    In purely literal terms, "nothing" cannot be observed and... by definition it does not exist.

    In practical terms, the past was an observable present and was a spring board for our evolution and development... yet we cannot observe it unfold. The past is our foundation yet all we can observe of it are the artifacts of light and objects that remain. So, the past "did" exist without our observing it, and now does only exist as a result of its unfolding.

    I think Heisenberg has the right approach. To define what's "real" one must be a human because that's all humans are concerned with. Nature, on the other hand, has no concerns and will continue on with or without our meager human evaluations.
     
  10. Apr 12, 2009 #9
    I'd be really careful to start any interest into quantum mechanics by reading someone like Keith Mayes. While he raises some good points, especially that it's incorrect to think that theoretical physics is all nicely wrapped up, he is also... a quack. If you're really interested in the subject, start with a less biased treatment on the subject... ie. someone who isn't looking to piece together statements about how science is incomplete to find room for God.
     
  11. Apr 12, 2009 #10

    baywax

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    My bet is that using quantum mechanics as a metaphor and an analogy for what we experience in a macroscopic reality is a macroscopic mistake.
     
  12. Apr 12, 2009 #11

    ...Funny that you would have such a blindingly subjective statement precede otherwise interesting insights on the profundity of the objective - unfortunately it makes any observant onlooker question the writer's own "objectivity".
     
  13. Apr 14, 2009 #12
    Thanks to everyone that replied.
     
  14. Apr 18, 2009 #13
    Perhaps we are being too anthropocentric. It may be the case that reality does not exist until it is observed. There is no inherent contradiction with this proposition and the proposition that reality existed before humans.
    This is due to the lack of a concrete definition for the word "observe". Why assume that only humans can "observe" reality? Perhaps even an electron can "observe" the proton it orbits. It certainly is "affected" by it. And we are "affected" by things and say we "observed" it happen.
     
  15. Apr 18, 2009 #14
    PAP's theory is not anthropocentric. One could argue its biocentric or observer-centric but it in no way puts humans in an causal role, other than that humans are a subset of the observers/definers which caused the universal wave function to decohere or collapse.

    Our problem is the copernican paradigm which has held science back since Bohr's Copenhagen Interpretation was formalised. Mainstream science is just not ready to reverse some convictions held for the last few hundred years.
     
  16. Apr 18, 2009 #15
    Thanks, that makes a lot of sense.
     
  17. Apr 18, 2009 #16

    baywax

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    This is what came to mind: On the outset, observation is an action or what a physicist would call "work" taking place that requires two or more events (events being the subject(s) and the object "doing" the observation) separated by a distance or difference of some kind.

    We tend to classify observation as a biocentric activity yet we forget that biological systems are composed of abiotic components... such as minerals and chemicals etc...

    So with a bit of a stretch we can say that the non-biological elements of biological entities are part of the act of observation. Why can't we attribute the act of observation to the non-biological components in entirety? The observation would not take place without the specific acids, nutrients and minerals in the first place.

    Does this mean that what is being observed is, in turn, observing the act of observation taking place... thus creating a "conversation" between two observers in every case of observation?

    We often say, perhaps metaphorically, that a piece of steel has "experienced" the stresses of a trauma or whatever. Can we accurately use the same form of analogy and say the piece of steel has observed the stresses of trauma?
     
  18. Apr 21, 2009 #17
    Perhaps a little anthropocentrism is allowable here as,after all,we are the beings doing the observing.Yes,maybe reality doesn't exist,although I think the evidence is overwhelmingly that it does.Do some believe that the moon doesn't exist when we do not observe it ?.Such a viewpoint leade only to solipsism which isn't very helpful to scientists.
    A central tenet of the Copenhagen Interpretation is that the wave function represents all that we may know about the system.Once we start considering our 'knowledge' of a quantum system,then consciousness must be taken as part of the measurement apparatus.Those who find this unacceptable must presumably therefore reject the Copenhagen Interpretation.
     
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