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Distinguishing order and disorder

  1. Jan 19, 2005 #1
    How do we know if a system is ordered or disordered? What may appear as order could be disorder. On the other hand what can appear to be disorder may be order at a level that we cannot preceive as order. I know David Bohm talks about this in his theory of implicate and explicate orders.
    Is it just a matter of semantics?
  2. jcsd
  3. Jan 19, 2005 #2
    Isn't everything?

    Seriously, though, I'd say that "order" usually refers to "complexity", which, in turn, usually refers to the amount of up-keep that would be necessary to keep it from decaying into "disorder".

    This is just off-the-cuff, cuz I gotta go quick, and I wanted to contribute something before I left :tongue2:.
  4. Jan 19, 2005 #3
    I think the general view is that order is in the eye of the beholder, as you suggest. Einstein said "The human mind has first to construct forms, independently, before we can find them in things." I suppose order is form, and the comment holds good for either.

    We usually link it to complexity, or the up-keep of complexity, as Mentat says, but complexity is not much easier to define than order, so I'm not sure doing this helps much.
  5. Jan 19, 2005 #4
    Well...that falls back on the old (and I'm talkin' Aristotle "old") concept of "universals" vs. "particulars". For example, if I see two rivers that run along side one another without ever intersecting or drifting appart, I will have observed a "particular" example of parallelism. However, to extrapolate from that there is such a thing as an abstract "universal" concept of "parallel", independent of the "particulars" (the observed instances), is a semi-Platonic notion.

    So, whereas we could view the thing in purely subjective terms (as you suggest), and say that we "know it when we see it", we could also try to rigorously define it.

    Well, actually, what I meant was that "complexity" = "necessity for upkeep" (at least, usually). I also meant that "complexity" = "order" (at least, usually). So, when one speaks of "order", one is probably speaking of the "necessity for up-keep, in order to keep the thing/system/phenomenon from ceasing to be as it is".

    Now think of the physical concept of entropy (crude definition: the level of disorder of a system). The greater the entropy of the system, the less up-keep is necessary to keep it as it is (that seems a reasonable assertion, doesn't it?). And, if we define "order" as synonymous with "level of up-keep necessary" then this makes perfect sense.
  6. Jan 20, 2005 #5
    Yeah fair enough. I find these issues confusing. Entropy is just as much an elusive concept to me as order, complexity, form etc. They all seems to be defined by reference to each other in a rather circualar way. For instance, the entropy of the universe is said to be increasing. But this implies negative entropy, and just as much as is required to have created the order in the universe that is now disappearing. Where did this negative entropy come from, and where is the order going? The two kinds of entropy must cancel out. So at t=o was the universe in a state of not requiring any up-keep or of requiring an infinite amount?

    I'm not disgreeing with anything you said. Just wondering what all these words really mean when it comes right down to it.
  7. Jan 20, 2005 #6


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    Its certainly not a matter of semantics - its math. 1,2,3,4,5,.... is ordered because there is a mathematical pattern to it. 5,34,6,... is not.

    Chaos theory is somewhat of a twist, but its mostly still systems that are disordered on one level but ordered on another.
  8. Jan 21, 2005 #7
    Wuliheron would say that everything is. What is "truth" if not the lack of "falsehood"; and what "falsehood" if not the lack of "truth"? "Alive"; "dead". "Ordered"; "disorderly"....

    I'm just saying that they are two sides of the same coin, but their interdependence for meaning doesn't require that they don't have meaning; merely that it's interdependent.

    The entropy is said to be increasing, which just means that it used to be lesser (i.e. the order used to be greater). The very fact that order requires up-keep makes it rather obvious (via common sense) that the disorder would be increasing.
  9. Jan 21, 2005 #8


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    If you have a cold block and hot block, the system of two blocks is ordered. If you touch them together and they become the same temperature, the system is disordered.

    To me it sounds like an ordered system is one with differences in it. The more similar each part of a system is to the others, the less ordered it is.
  10. Jan 21, 2005 #9
    That's a very interesting concept.

    It does seem that, e.g., in cosmological theories about the end of the Universe, the increase in entropy eventually leads to everything being "similar" (as you put it).

    Perhaps the need for up-keep is simply a reflection of the difficulty of keeping different types of things together.
  11. Jan 21, 2005 #10
    If I read that right I agree.

    I'm not so sure that this is common-sense. It would suggest that at t=0 the universe was in a totally ordered state, and that at t=the end it would be in a totally disordered state. I would have thought it more likely that it will end in the same state as it began. By this I mean that it seems more likely that at the limit (but only at the limit) order and disorder are indistinguishable or, perhaps, a false distinction.
  12. Jan 22, 2005 #11
    Why? If perfect order existed at t=0, and the tendency toward disroder is taken to be the case, then the end would be perfect disorder. In fact, if "order" is defined as the "need for up-keep", then both the tendency for disorder and the end-as-perfect-disorder become common-sensical (or, if not, at least logical).
  13. Jan 22, 2005 #12


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    Also: If every part of the universe was exactly like every other part, it would be very ordered because this is a very unlikely scenario. So every part being like every other may not be correct either...

    I think I'm going to with 'disorder is what's more likely to be around' Rocks don't line up into neat lines by themselves, they get scattered at random.
  14. Jan 23, 2005 #13
    well this is going to sound strange, but i dont think order and disorder exists on an objective level..

    it seems to me, as with everything, you need an observer to classify something as disorderly.
    our universe seems orderly to us because we're part of it, but to someone on the outside it may look like total chaos.
    it's almost as if nothing exists if nothing is there to observe it.. well that was a bit of a tangent..
  15. Jan 23, 2005 #14
    But to define disorder as what's more likely is to assume that the second law of thermodynamics is true, while defining one of its essential terms. This is usually considered a philosophical faux pas.

    For an example, think of the materialist/idealist debates. When materialists (more accurately: physicalists) try to define "physical" as that which interacts or that which can be talked about or something like that, there assuming their belief (that all things are physical) in the defining of an integral term.
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