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Time: Continous or Discrete?

  1. Jan 5, 2004 #1
    Ive been reading different points of view and theories regarding this topic. Wich is, currently, the most reliable one?

    P.S: Had red a nice one explaining that time, in human perception terms, is discrete, because the brain needs at least the change of the smallest quanto (1 bit?) of information to work (to be able to perceive anything).
  2. jcsd
  3. Jan 5, 2004 #2


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    Whether or not time is continuous or discrete has nothing to do with human perception. Humans have been around a relatively short time (modern humans less than 200,000 years) compared to the universe. Time existed before there was any life.

    As far as time being continuous or discrete from physical theory, the question is open. For example, loop quantum gravity has time as discrete. General relativity operates in continuous time. Only time will tell.
  4. Jan 6, 2004 #3
    har har...
  5. Jan 6, 2004 #4

    Chi Meson

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    Check this old thread regarding "chronon vs. Plank time."

    Chronons are a theoretical discreet particle of time. Plank's time is a very tiny amount of time; it seems to be the smallest meaningful amount of time.
    Last edited: Jan 6, 2004
  6. Jan 7, 2004 #5
    Yes, and when time stopps we will percieve that it has stopped and the discovery will be made. TIME HAS STOPPED. It will be broadcasted over the entire world network next year.


    we cannot percieve time as stopping, because we would stop percieving in the process of time stopping, therefore time is continuous IN THE PERSEPTION OF THE HUMAN MIND.
    The only way to percieve time as stopping is to isolate ourselves from whatever time is, and measure it without having the isolated (controlled) time interfere with the experiment.
    Last edited: Jan 8, 2004
  7. Nov 2, 2004 #6
    Now any other ideas?
  8. Nov 2, 2004 #7


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    Yes, we could not tell, because we are contained in it, if it stopped we wouldn't notice, as far as we know, it could stop all the time, and/or speed up whenever, since we're contained in it. If you were to imagine a closed container, you are suspended in the middle, floating, with no way to communicate with the outside world. The box could be going trillions of miles an hour, abruptly stop, to zero, then speed up to 7,000, you wouldn't know because you can't see it from the outside, or watch the outside.

    Could we in any way, ok, this is crazy... perceive time from outside time. Watch a parallel universe from another one?
    Last edited: Nov 2, 2004
  9. Nov 2, 2004 #8
    "Could we in any way, ok, this is crazy... perceive time from outside time. "

    In a specific sense it's a natural thing in noncommutative geometry :-)
  10. Nov 2, 2004 #9
    I am not sure, but it seems possible. Alternate dimensions is not in my list of intrests.
  11. Nov 2, 2004 #10
    Has time been proven to actually exist? It's a measurement; a comparison of events; the swing of a pendulum or vibrations from the atoms in caesium vapour; whatever, it's counted and compared to other events. Time exists mathematically and is very useful, as are other dimensions, but a meter exists only in the sense that we have a stick designated as that long and stuff to compare. Is time any different?
  12. Nov 3, 2004 #11
    Well, if you look at time in Relativity, time is able to be distorted. This, for me, is proof enough that it is real.
  13. Nov 3, 2004 #12
    I would disagree. I think you'd hit the wall if the container was abruptly slowed down or accelerated. What this make in the analogy with time is an open question.

    The question is wheter we can divide time into infinitly small pieces or not, right?
    What is time anyway? Can we divide something if we don't even know what it is?

    Well if there's an definite smallest particle/string/loop/wave whatever you like that cannot be divided into smaller components, maybe time is of the same nature?

  14. Nov 3, 2004 #13
    hittting a wall is only an effect of inertia.
    we can divide mass by volume to get density, so we obvioulsy can divide time into some quantative value. By my experience time is continuall due to human perseption, but it is continuous at a rate. This states that time can be split into values such as seconds, hours, minutes, days, months, etc...
  15. Nov 3, 2004 #14

    Les Sleeth

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    I agree with you CeeAnne. There is no "time" with existential qualities. I've argued at PF many times that time is simply how we measure the rate of the universe's entropy (as in: overall rate of disorganization). What we do is use situations or things that cycle, almost like a metronome keeping beat. Why that works is because if the universe continues heading toward disorganization, it will evenually destroy all regularity. Since regularity is what allows cycles, it makes sense to use the regularity of cycling things as yardsticks.

    If that is true, it gives us the means to decide this thread's question. I say time is both discrete and continuous. Because the last cycling thing to go will be the oscillation associated with quantum processes, and because we know quantum processes occur in discrete units, then we also know that time progresses in discrete steps. But since there is no known circumstances where entropy fails to prevail overall, time is continuous too. In other words, micro-time proceeds discretely, and macro-time proceeds continuously.
  16. Nov 3, 2004 #15


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    Sorry, my analogy was incomplete, if there was no smashing into walls inertia... heh, I think you know what I mean. No?

    What is the other side of the arguement? How is time not a measure of process comencing in the universe? And I see micro-time compared to macro-time as an interesting thought...
  17. Nov 3, 2004 #16

    Les Sleeth

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    I don't think two sides are implied in what I said. If time is what I say it is, then I should be able to use that model to describe time in terms of your question, ". . . is time not a measure of process commencing in the universe?"

    I assume you are referring to the fact that time is said to commence with the Big Bang (if not, then forget what I'm about to say :redface:). From the very first moment of the universe's inception we can now see entropy was in charge. At first of course it looked like everything is getting organized, which it was. But just like if you look at life during the formation of the fetus you might say the law of entropy is being violated (but later when the person dies it is clear overall it wasn't), so too can we now see that the universe appears it was fated for disintegration from the moment it came into being.

    It would have been exceedingly difficult to measure the rate of entropy in those opening moments. Now we can do it by averaging all the entropic change since the Big Bang.

    Why is time so hard to understand? One reason could be relativistic effects, as avemt1 mentioned, "Well, if you look at time in Relativity, time is able to be distorted. This, for me, is proof enough that it is real."

    Let's try out the time-as-entropy-rate model on that. If time is the rate of entropic change in the universe, how could it be altered? Well it turns out, for example, that gravity and acceleration tend to retard entropy because they slow particle oscillation rates. Since, according to the entropy rate model, there are only so many oscillations remaining in matter before the universe disintegrates, a slower oscillation rate at some spot (like an accelerating space ship or neutron star) means "time" (i.e., entropy rate) proceeds more slowly than frames of reference not subject to acceleration or the intense gravity of a neurtron star.
  18. Nov 4, 2004 #17
    all right you caught me, but we are talking about time here not inertia.
  19. Nov 4, 2004 #18
    This sounds like the properties of the wave of light: As the vibration increases energy is decreased, but as vibration decreases energy is increased. If you substitute acceleration for energy and vibration of wavelength for vibration of matter you get the same result. Correct?
  20. Nov 4, 2004 #19

    Les Sleeth

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    That's how I see it. In a thread I started a long time ago I asked if light ever spontaneously lost energy. Marcus was kind enough to explain how the microwave background radiation still hanging out in the universe since the era after the Big Bang appears to "stretch" in wavelength as the universe expands, which of course means it surrenders energy. That, in the rate-of-entropy-as-time model I've suggested, would be considered the "aging" of light.

    I wonder if background microwave radiation would serve as the best timer possible in our universe since if we had our clocks tuned to its frequency, our clocks would be slowing pretty close to the rate the universe is winding down.
  21. Nov 4, 2004 #20
    Does the "aging" of light oppose relativity?
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