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The dimensionality of time

  1. Mar 21, 2013 #1
    As a true novice in this field...

    Do theoretical physicists consider time to be physically dimensional in the same sense that distance is? Or is the dimensionality of time only conceptual shorthand--a function of how perceiving agents incrementally organize successive configurations of mass in flux within space?

    In effect, isn't "time" merely the measured release of an otherwise static universe? Might it simply be thought of as displacement potential itself? As such, the term "space-time" would be just another way of describing a universe where change is possible, but only in accordance with a prescribed progressivity.
  2. jcsd
  3. Mar 21, 2013 #2


    Staff: Mentor

    I can't think of an experiment which could be performed to answer your question.
  4. Mar 21, 2013 #3


    User Avatar

    Staff: Mentor

    "displacement potential"?
  5. Mar 21, 2013 #4
    Hi, RealityQuest. For someone with a handle like yours it's quite possible you may have an interest in foundational physics. You may be aware that there are at least two or three concepts favored among physicists: 1) The physical universe is 3-dimensional, evolving with time, 2) It's a "block universe" --the idea that the universe is a static 4-dimensional structure populated by 4-dimensional objects, and 3) Those who consider either 1) or 2) as possibilities but feel there is not the experimental evidence to resolve the issue.

    From a number of previous posts on this forum related to your question, I would guess that most here are of the 3) view.

    It has been pointed out here that given the observation that the speed of light is the same for all observers, regardless of their relative speeds, this is ample evidence to infer a block universe. This is because the only universe scheme that has so far been imagined is one of 4-dimensions (X1, X2, X3, and X4) with objects strung out along 4-dimensional space-time paths called "worldlines." An observer is characterized as at rest in his frame of reference (coordinates X1 = 0, X2 = 0, X3 = 0) while moving at the speed of light along his X4 axis. Distances along his worldline is measured with a clock: X4 = ct.
    Last edited by a moderator: Mar 22, 2013
  6. Mar 21, 2013 #5
    The universe seems to be something between perfectly static and perfectly chaotic. Motion is allowed, but limited by what we call inertia.

    In a perfectly static universe the displacement potential of an object would be zero. In a perfectly chaotic universe the displacement potential of an object would be infinite.

    In our universe, given limited mass and force, the displacement potential can be definitively calculated in relation to cycles completed on a referenced clock, such as the rotating earth. Zero earth rotations, zero displacement potential. One earth rotation, one day's worth of displacement potential. Actual displacement depends on the mass and force applied.
  7. Mar 21, 2013 #6
    Thanks for your patient response.

    Clearly I find myself in the 1) camp. You've given me a lot to consider.
    Last edited by a moderator: Mar 22, 2013
  8. Mar 22, 2013 #7
    Sorry I won't be able to participate here. I don't seem to have the intellect to understand any of what you are trying to communicate about potentials, etc.
  9. Mar 22, 2013 #8


    Staff: Mentor

    This thread is already becoming speculative.
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