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Time or change

  1. Feb 12, 2010 #1


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    what was first: the time or a change?

    a) time
    - time enables changes
    - time exists physically
    - spacetime exists physically
    - gravity/acceleration bends local time
    - high speed bends local time

    b) change
    - changes enable us to create concept of time
    - time exists only in our thoughts
    - gravity/acceleration prohibits/slows local changes
    - high speed prohibits local changes, because propagation can't be faster than light
    - traveling back in time is not possible, because history of all changes is not "saved" anywhere

    which one is closest to the reality?

  2. jcsd
  3. Feb 12, 2010 #2
    I see what you are getting at, and from time to time I have struggled a bit with this idea before. But I don't see how it is possible to seperate the two, since "change" by definition involves "time", and "time" by definition involves "change". I don't see how one can be thought of as different from the other.

    I'm just commenting on the general concept here, not the ten claims.

  4. Feb 12, 2010 #3


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    Staff: Mentor

    Thread moved to philosophy.
  5. Feb 12, 2010 #4
    I think you start the stopwatch after things start moving. Not before. Unless you are an intelligence who can be prompted to move on command or move other things on command.
  6. Feb 13, 2010 #5
    Technically, we don't know precisely what enables change.
    We know about quantum physics but we don't know why the particles move per se.
    Time is usually a measurement of the speed of change is it not?
    Change itself must be some fundamental property of mass and light but nobody knows exactly what that means or what it is.
  7. Feb 15, 2010 #6


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    Isn't change a result of energy (ability to do work... like change)? Without energy there would be no change... unless we can prove the opposite, I'd say energy is the cause of change.
  8. Feb 15, 2010 #7
    Ever-present and eternal Awareness spontaneously and effortlessly created our Universe (made all the particles in it and put them into motion, and via natural laws defined how particles behave and interact among themselves).

    Change is a matter of a physical thing, while time is simply a measure of that change.

    As Einstein nicely put it: "Time is what clock measures." (quoted from memory)
  9. Feb 15, 2010 #8
    What clock actually measures and what it shows isn't the same thing though, is it?

    That which it shows is what is suitable for a human being...

    It would be stupid for us humans if the lowest measured time unit would be a year, it's way more useful to organize our day when we act on hours and minutes etc.

    And if we'd be creatures living only 1 minute of a human time, it would be stupid for us if we'd use days, months and years, since even seconds would be to us more than a year to a human...

    So, clock shows us what we want us to show not what really time is. ;)

    But then... what is time if not what clock measures?

    IMO, time is the most fundamental and universal change in our Universe, present everywhere, and that's the change due to expansion of the Universe. And this change is what started with the birth of the Universe and is still going on.

    Time and change are in this sense not the same thing. Time is Universal expansion while change is that too, but many other things as well.
  10. Feb 22, 2010 #9
    A clock counts changes, or a clock counts repeatable motion, because it is a adding machine. A clock does not measure motion it counts it, it does not measure changes it counts changes.
  11. Feb 22, 2010 #10
    How about thinking of a photon as one instant of time, all of the change in the photon is through space as it moves into your eye. Your eye on the other hand even at rest in space, is still dilating through time at c to receive it. It is the space time interval of 299,792,458 meters per second as measured by all observers that is unchanging in the present for each observer.
    Last edited: Feb 23, 2010
  12. Mar 3, 2010 #11
    The change happened first. If everything was the same, I mean everything, we would have no perception of time. It sort of goes along with the second law of thermodynamics. The law states that things are constantly going through entropy and irreversible processes, therefore it takes time forward, rather than backward. Because if you saw a crinkled up piece of paper "morph" back to normal just like its normal state, time would be different.
  13. Mar 5, 2010 #12
    Time or change, there can not be change without the time needed for the change, but having time with no change happens all the time. Think of a pulsar, we measure a burst of photons and when they stop we will measure the gap between the bursts as if it were moving at the same speed as the photons, a measure of time without change?
  14. Mar 5, 2010 #13

    Char. Limit

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    They are simultaneous, perhaps.

    Time began at the exact moment the first change occurred. Suggests to me simultaneity.
  15. Mar 5, 2010 #14


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    You only notice the gap because of the bursts. Each condition is a change by comparative analysis.

    Change is the measurement of differences between conditions. Time is a measurement of change.

    You measure a distance by measuring the change in proximity to point a. or b. Even if there is no activity between a and b... one can still measure the each point between them. By doing so one can calculate the amount of changes it will take in fuel or velocity and other conditional changes it takes to get to point b. This is measuring the number of changes it takes to get to point b... this is measuring the changes required to traverse the distance. The process has been simplified by using time as the means of measuring change.
  16. Mar 5, 2010 #15
    Change. Time is just a human construct used to track change.
  17. Mar 5, 2010 #16
    Why do you think one came first? Time is a measure of change; one doesn't "come" before the other. Can you have a change without a time during which it occurs?
  18. Mar 6, 2010 #17
    Change is the difference between conditions that a clock counts, but time like the photon dilates at c. The difference between them, I would think, is the photon only moves in one direction while the duration of time moves outward in every direction a dilating area that allows a photon not only enough time to move through without gaps but also a direction to move in.
  19. Mar 7, 2010 #18


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    I would have named this thread "time or temperature."

    Since time is always measured in reference to speed of movement; it does not have a universal measurement, it is localized, and relative. So, there is no "Time" as you seem to imply.

    Thermodynamics connects time's directionality ("arrow") to increasing entropy. This thread highlights another, often overlooked, connection: the one between time and temperature. If local time is kept according to the movement (speed) of molecules, then the lower the temperature, slower the time.
  20. Mar 8, 2010 #19
    I think that if you think of a clock as counting the cycles then temperature is a measure of the duration of each cycle. The more energy in the form of heat the shorter the cycle and the faster the count, while the less energy measures the longer duration as a slower count. As for the arrow of time is outward from every point the same as heat, and change seems to me is always a exchange of energy anyway.
  21. Mar 9, 2010 #20


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    The difference here is that you can time the changes of temperature but you can't use a barometer or a thermometer to gauge your clocks behaviour. But you have the right idea in that the changes that occur in temperature are measured by the thermometer much in the same way an atomic clock measures cesium atomic resonance, giving us a somewhat stable reference for "time". However, this type of measurement of change may or may not resonate with the macroscopic world's sense of change and time.

    The sun has always provided a good reference for "time" or the measurement of change. I think they may have come up with the atomic clock thinking that we'd be jolly adventurous space travelers by 1971, away from the reference of the cycles of our solar system.
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