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What is time?

  1. May 1, 2013 #1
    Never mind. Delete thread please.
    Last edited: May 1, 2013
  2. jcsd
  3. May 1, 2013 #2
    I deleted my originally question because I figured no one here has any idea what time really is.
  4. May 1, 2013 #3


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    Gold Member

    I take it YOU have some idea what it is, why don't you tell us?
  5. May 1, 2013 #4
  6. May 1, 2013 #5
    Time can be loosely defined as "the distance that something travels through 4d space". It is a vector quantity.

    Clocks do not measure time, they measure cycles (the frequency of a given repeating event over a certain distance). However, you can derive time from a clock's measurement.

    Conjecture: the past, present, and future stuff is completely nonsensical. There is nothing but the present.

    The past is an illusion, arising from the fact that the observation of our experience is based on the motion of photons. More sophisticated technology than the eyeballs you were born with can produce results which hint at the concept of symmetry (that distance itself is also an illusion).

    The future is a fabrication, as far as we can tell. It is a purely human construct, used as a logical placeholder for "the things that could possibly happen."

    What you probably think of as the "past" and the "future" are not "places" that you could go, ever.
    Last edited: May 1, 2013
  7. May 1, 2013 #6
    I'd say you're describing holographic motion, not time.
  8. May 1, 2013 #7
  9. May 1, 2013 #8
    "Trollegionaire" is not a very subtle hint about your purpose here.
  10. May 1, 2013 #9
    I agree.

    Btw, here's what I originally posted:

  11. May 1, 2013 #10
    You're on the right path, and yes, your concern is very valid.

    The commonly accepted definition of time is horrible.

    It is seriously a Nobel worthy thing, just waiting for someone to come and do the math.
  12. May 1, 2013 #11
    By holographic motion, I'm referring to the tool of measurement used to describe changes of a 2-dimensional structure.
  13. May 1, 2013 #12
    Wow, it's good to see someone with similar opinions and concerns.

    I completely agree, man.
  14. May 1, 2013 #13


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    Science Advisor

    ##\Delta \tau = \int _{\gamma}[g(\dot{\gamma}, \dot{\gamma})]^{1/2}d\lambda ##
  15. May 1, 2013 #14
    This has been quite illuminating.
  16. May 1, 2013 #15
    I'll add to your idea that distance is an illusion, and you're right. What we humans refer to as distance is a result of our inherent disability to (theoretically) be omnipresence, i.e our observations are singular, and our line of sight is not spherical, only if sequentially. This results in a spatial deficiency that requires the observer to construct images based on memory and delays in the cyclic nature of reality.
  17. May 2, 2013 #16


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    Time is nothing but a unit of experience. It represents the separation of energy and matter as past, present and future are torn apart and expansion is given to the universe for us to observe and measure. Time is nothing but a unit of experience, as once we die time will cease to exist and all energy and matter will come back together to form one. Without experience there is no time in which to observe and no universe to measure at all. Time is nothing but a unit of experience.
  18. May 2, 2013 #17
    "Unit of experience"? Sounds like mumbo-jumbo to me.
  19. May 2, 2013 #18


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    I'll care to hear your interpretation of time when your physical body is dead and your consciousness no longer here to experience it.
  20. May 2, 2013 #19
    Time is a quantity which defies a precise and logical definition. That's the reason Newton didn't attempt to define it in the Principia. Newton wrote Absolute, true, and mathematical, of itself, and from its own nature, flows equably without relation to anything external, and by another name is called duration. Newton made no attempt to define either space or time and for good reason.

    The reason being that when one attempts to define it the definition becomes circular. An excellent discussion can be found in this wonderful discussion - http://users.wfu.edu/brehme/time.htm [Broken]

    One thing it can definitely not be thought of is the distance that something travels through 4d space". It is a vector quantity. The reason being is that it uses a term "4d" which requires knowing that it is. And the 4d space is spacetime and one defines spacetime as the sum total of all events where an event is something that has a location and a time associated with it. Thus the circle is complete. It also misuses the term "distance" since that term properly reserved for spatial measurements, not temporal ones. What he's referring to is the spacetime interval. It's also meaningless to speak of something as "traveling" through spacetime because travel is defined to refer to spatial motions.

    You can think of time as that which is required for the relationships between objects located in space to change either by a property or by a spatial translation. Operationally one defines time as that which is measured with clock. That's how Einstein operationally defined it.
    Last edited by a moderator: May 6, 2017
  21. May 2, 2013 #20


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    Think of it like this. How is it possible that a particle can be in two places at once? It's because the particle isn't bound by our laws of logic and reasoning where time has a beginning and an end. The truth is time doesn't even exist, it flows forwards, backwards and stands still all at once, this is how the particle can be here or there or even entangled across vast distances of space without any incident of time between them. Without experience the particle is neither here nor there but is in fact in all possible places at once, until we take it upon our selves to make an observation. Therefore one can conclude it is our gift of experience and our willingness to make observations that brings to life the dimensions we call time and space, without it all the doors of posibility are wide open.
    Last edited: May 2, 2013
  22. May 2, 2013 #21


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    Staff: Mentor

    Like all the many other threads we've had on the subject of "what is time," this one has devolved into metaphysical / philosophical noodling, and is therefore now closed.
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