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Time as an Emergent Property

  1. Jan 13, 2006 #1
    What are your thoughts, in general terms, on the notion of time as an emergent property? In what ways could time be a product and side effect of some other, move fundamental process or entity? I've been thinking on it, and I thought some other people's thoughts would be useful.

  2. jcsd
  3. Jan 13, 2006 #2
    Time is change. The concept of time is meaningless if nothing changes, and no change can happen unless time passes. These two concepts are equivalent so time is simply the fact that reality (whatever it may be) is not in a constant state.
  4. Jan 13, 2006 #3
    Right, which is why it (obviously) couldn't be a temporally emergent property. However, that does not mean that time couldn't be a by-product of some more fundamental entity that does NOT change; there could be some entity that logically necessitates some method for "change", but not conversely; alternatively, there could be some law or entity that requires a process to exist and therefore provides a method for times "creation".

    The concept of gradual change is meaningless without time, but logical implications and the like can still be seen as emergent properties if the realities by which they are implied are fundamental.
  5. Jan 13, 2006 #4
    Existence. Existence makes change necessary because if nothing changed then nothing would exist. Here's why.

    If the word "exist" is to mean anything at all then there must be a difference between existing and not existing. Consider a set of pool balls as the universe. Everything that matters to this universe is how balls interact as time passes, or equivalently as changes happen. The only way any ball can exist in this universe is by interacting with other balls because if a ball never interacted with any other then it could not be said to exist: there would be no difference between existing and not existing. Of course we must define the universe properly as "all there is" then not assume an external observer who can see this independent ball, which would also render the word "universe" meaningless. So given "all there is", if something has no effect on anything else, it simply does not exist.

    Now consider that all balls remain where they are. This being the case, no ball interacts with any other, so there is no difference if any of them exists or not, again denying the possibility of an observer external to "all there is". Since no ball has any effect on anything else in a constant universe then a constant universe cannot exist. Conclusion: existence requires change.

    Edit: typo.
    Last edited: Jan 13, 2006
  6. Jan 13, 2006 #5
    That's actually really helpful.... Thank you.

    However, couldn't you apply the same argument to space; or to the balls themselves? If the balls do not exist, obviously nothing can interact and hence nothing exists. However, it is possible for the balls to not exist and for something ELSE to exist in their place that provides the same function: interaction. There could be lions instead of pool balls--and, in a world of pool balls, it would be essentially impossible to concieve of a lion. Similarly, couldn't you say that some mechanism allowing change but somehow different from time could be possible, and that since time may not be the only mechanism for change, it isn't conclusively implied by existence? (Not, of course, that I can think of something (at the moment, anyway) that would perform the same function as but remain distinct from time... It just seems that it's possible; in fact, non-relativistic time would be one example: it isn't necessary for time to be relativistic (or space, for that matter) in order to allow change and interaction--hence, existence does not actually predict, by itself, the kind of time that actually exists)

    Or do you think there is some way in which it does?
  7. Jan 13, 2006 #6
    Sure, the rationale applies to anything: balls, space, elephants. If it exists then is must matter to something somehow. If it matters to nothing then there is no difference between existing and not existing so I simplify to non-existence. But in order to matter, in order to exist, then something must change, and so existence of anything implies change.

    But I don't like to talk about time. It's an ill-defined term that gets a lot of abuse. Personally, I'm incapable of differentiating time from change. What a clock measures is change (of a pendulum, a crystal, an atom, anything that appears to change with regularity). Time on the other hand is a literary device used by science fiction writers to entertain crowds. Start discussing time and you've got a long fruitless debate on your hands...
  8. Jan 21, 2006 #7
  9. Jan 22, 2006 #8
    Maybe you could say that time is the result of the second law of thermodynamics, which is that entropy in the universe will always increase (unless equilibrium is already reached). The Universe started in a very ordered fashion with a huge amount of energy in a small amount of space. The universe than 'automatically' expanded so the total entropy of the universe had to increase. This compulsory push towards increasing entropy meant that change must happen, which in turn meant time must be avaliable. Because without time, entropy cannot increase. As the universe continue to expand, entropy must increase therefore time must be present.

    So time resulted from the second law of thermodynamics.
  10. Jan 23, 2006 #9


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    Tomorrow, at my institute, we have a talk by Etienne Klein here:

    I'll try to attend it and see if it brings any clarity to the discussion...
  11. Jan 24, 2006 #10
    Time is a simple measuring system we use to keep track of change.

    We are the emergent property. If the concepts our brains come up with, like time, are to be considered a part or product of us... then it could, with a bit of a stretch, be considered an emergent property as well.
  12. Jan 25, 2006 #11


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    I hope you do attend, I'd like to hear what you think of it.
    And, Maaneli, thankyou, that was very interesting.
  13. Jan 25, 2006 #12
    There is one fatal flaw in Orefas thesis, and that is the fact that nothing would be able to change without time.
    Time isn't just equal to change, because obviously without any sort of system to guide HOW something move in space, would would it move?
    It seems also that everything moves at the same "speed" relative to eachother.
    While the speed we measure is relative to our earth, on earth itself, the speed of the objects never change.
    80 MPH will always be 80MP, relative to earth.
    When we experience time going forward, in our consciousness, then time is always going at the same pace.
    If we throw a ball, then we expect that ball to have a certain speed, and certainly, it will always have that speed we predict.
    if time increased its pace, the ball would go faster.

    If then time is just a property of the interaction of the most basic building blocks of the universe, then time can be said to be emergent of those rules.

    But the question remains, is time an emergent property of the laws of physics, or is it a dimension of sorts, that is intertwined in the matter, but independent of the matter itself.
    If wee were to look at everything in the universe as one thing, then time could very well be another emergent property of mass.
    I guess time will tell.
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