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Does Time Exist?

  1. Jun 27, 2011 #1
    Does time really Exist? Is there a single equation proves the existence of time?
    What is time? :smile:
  2. jcsd
  3. Jun 27, 2011 #2
    I don't know the answer to that, but it seems a bit like asking is there a single equation that proves the existence of length, height of width.

    Also, as equations are basically a way of explaining the real universe mathematically, it seems that asking that sort of question creates a bit of paradox. If we experiance it, we know it is real.

    Anyway, that is probably a bit too philosophical and not what you were after! :~)
  4. Jun 27, 2011 #3
    There's no definite answer, but there was a great episode of Through The Wormhole on this exact question on the science channel recently and it covered quite a few theories.
  5. Jun 27, 2011 #4


    Staff: Mentor

    What do you mean by "really Exist"? Do you have a definition or experimental procedure that allows us to distinguish between things that "really Exist" and things that don't?
  6. Jun 27, 2011 #5


    Staff: Mentor

    I suspect there is not even a definite question. You need to have a definite question before you can even hope to have a definite answer.
  7. Jun 27, 2011 #6
    for us to prove the existence of time we must first establish the definition of time. as you see described ratherwell by Einstein should you read his papers. However a logician would point out to you that should time not have existed, you wouldn't have been able to finish the sentence you just posted online, therefore there is a passage of some quantity that allowed your motion through space
  8. Jun 28, 2011 #7
    IMO, "change" proves the existence of time, far as how we define time goes. One such equation ... t=d/v. Time is the natural progression of events perceived by material entity. It's likely that our notion and definition of time is yet incomplete. Time will tell :)

  9. Jun 28, 2011 #8

    Yes, sir :smile:

    Yes, sir :smile:

    Where where where ? where can I read his papers, sir? huh? :bugeye:
  10. Jun 28, 2011 #9


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    But I disagree with ardie's assertion that Einstein somehow defined time. DaleSpam's #4 is right on target, IMO.
  11. Jun 28, 2011 #10
    http://www.fourmilab.ch/etexts/einstein/specrel/www/" [Broken]

    Last edited by a moderator: May 5, 2017
  12. Jun 28, 2011 #11
    This is a very philosophical debate indeed - is time simply a means of quantification or is it some kind of ethereal absolute?

    I read Jim al-Khalili's book about Quantum Physics some time back, and I'm sure it was in there that he brought up the concept of having an infinite multiverse.

    I contemplated an extension of this, that being that if we, as conscious entities, were constantly jumping into a new universe at immeasurably fast rates, were we actually standing still in time while the multiverse moved around us? More like existing as a sequence of multiversal snapshots, kind of like when you make a flip book with a little stick man doing different things.. you flip the pages, and it makes him look as if he's moving.
  13. Jun 28, 2011 #12
    You could think of this anyway if time is quantized at the Planck scale. But whether there actually exist pages in your flip-book other than the current one I doubt very much. To paraphrase Gertrude Stein:

    'There was no then then.'
  14. Jun 28, 2011 #13
    We can't "prove" much of anything. I don't think we could even get a definition of time with which most would agree:

    Wikipedia provides one view:


    You can read a few comments there about an operational definition of time....a convenience so we can proceed to measure things....

    But we do need to think about such things, else progress will never be made.
  15. Jun 29, 2011 #14
    According to Google, this post had a page 2, and I seem to recall it being longer. Whahappened?
  16. Jun 29, 2011 #15


    Staff: Mentor

    The moderators determined that some of the content was in violation of the PF rules and so they removed it.
  17. Jun 29, 2011 #16
    It must have been for one of my best lines; in other words, one of my worst lines.
  18. Jun 30, 2011 #17
    .I would define time in relation to the change in objects . If an object moves from point X to point Y, the difference in it's state between the two points could be described as a product of the time passed.
    For example, a neutron moves from point X to point Y. At point X it has a value of 1 (no specific value). At point Y, it has a value of 10. This means that an increase of 9 has occured.
    It is impossible to quantify time, so it is best described as an infinite variable. Meaning it's value depends entirely on the values that have changed.
    Going back to the example, the time would be given as the distance divided by the magnitude of the change in the value.
    Time need not, however rely on distance to be calculated. It could be any variable that changes. If a value does not change, then it's change is zero, which still is a value.
    A millenium is as effective at quantifying time as a picosecond- they are both frames of referance by which a system can be examined, and the states at the start and end point compared.
    Time could therefore be seen as not a property of nature, but an effective way for humans to referance the change in a system.
    Sorry if i was really bad at explaining this, i will try to clarify in response to questions
  19. Jun 30, 2011 #18
    Let us for a moment define time. It is/was/will-be something that will extend from the present into the future, and did extend into the past. Any problems with this claim?

    Obviously, not all of time exists at the present. Consider what "exist" means. Exist refers to the present. It has other tense to refer past and future. Any disagreement here?

    Some of time was in the past and some will be in the future. Does anyone wish to claim that time is presently in the future or that time is presently in the past?

    The "presently past" is something I would call an oxymoron. Anyone have a problem with that?

    Words have shared meaning. Words are the majority conveyence of information on this forum. Bending them around to fit drawings on paper to razzle-dazzle readers should be left to Brian Greene, in my opinion.

    If I claimed the future does not exist, would anyone have a problem with that?

    If I claim the past does not exist, would anyone have a problem with this?
    Last edited: Jun 30, 2011
  20. Jun 30, 2011 #19
    I think it's currently impossible to tell if this is true or not, it could be the future and past actually do exist but are just "invisible" to us since we live at the "now". But it could also be that "now" is all there is, how would you go about proving such a thing?
  21. Jun 30, 2011 #20


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    I don't know why this topic keeps popping up like a zit.

    What if a phenomenon is characterized by the property of something. Would that qualify for that something to "exist"? Case in point: an object is characterized by its dimension. Does that imply that "space" exist?

    If that is so, then look at the numerous phenomena that are characterized via the broken time reversal symmetry (google it. You'd be surprised at what you would find as some of the more "common" things that are described by such symmetry breaking).

    So now, ask yourself this. If these things are characterized by the symmetry of something, wouldn't it be rather silly for that "something" to not exist? After all, we depend on it, both qualitatively and quantitatively, as a characteristic in describing such phenomena. Is this a typical description for something that doesn't exist?

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