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Space without time?

  1. Mar 14, 2007 #1
    I was reading on relativity and the speed of light being constant and I thought of a something that seems too farfetched to be even remotely true so I won't throw my homegrown crackpottery at you right now, but I have a question though.

    Is it possible to have space and matter without time?

    :uhh: this probably sounds like one of the elemetary questions you always see (kinda like "if i was going at C, what would light look like?") but I cant think of anything outside of time and space being together, so I turn to you for help
     
  2. jcsd
  3. Mar 14, 2007 #2
    I think space and time are always present together.....
    in SR,with a change in measured time,changes also take place in measurements taken in space....(I mean both are relative)

    Space and time co-exist
     
  4. Mar 15, 2007 #3

    Danger

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    Space and time are considered to be different dimensions of space-time, as far as everyday science goes. There might be some mathematical scenarios wherein one can exist without the other, but I don't think that it can occur in reality.
     
  5. Mar 15, 2007 #4
    Space without Time = Time without Space.:smile:

    And that's all I can say (bits of physics philosophy)
     
  6. Mar 15, 2007 #5
    In a way, space-time is space without time.
     
  7. Mar 15, 2007 #6
    Perhaps in a metaphysical sense - but not on these forums
     
  8. Mar 15, 2007 #7
    no, i dont mean metaphysical. what i'm thinking of is more of the quantum world
     
  9. Mar 15, 2007 #8
    I remembered I read somewhere that the dimension of time is the result of quantum fluctuation from a 4+0 dimensional space without time. :grumpy: I think it's mentioned in "Time Travel in Einstein's Universe: The Physical Possibilities of Travel Through Time" by J. Richard Gott.
     
  10. Mar 16, 2007 #9

    Demystifier

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    Einstein equation certainly possesses solutions in which the metric has the signature (++++). In other words, it is possible that only spacelike (or only timelike) distances exist. In this sense, space without time or time without space are possible, at least theoretically.
     
  11. Mar 16, 2007 #10

    Mentz114

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    There's no time in LQG. You have to make it up as you go along.
    Seriously, with no time it's not possible to define change so the timeless universe just freezes and is of no interest (?)
     
  12. Mar 16, 2007 #11

    Demystifier

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    Are you claiming that there are no changes in LQG and that LQG is of no interest? :rofl:
     
  13. Mar 16, 2007 #12

    Mentz114

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    Certainly not. The two sentences should be taken separately. The first word of the second sentence implies that the line above should not be taken seriously.

    I know that in LQG a quantity which always increases can be found, against which to compare other things to define change.

    But I think some sort of 'time' is required to define change.
     
  14. Mar 16, 2007 #13
    Mathematically -> 4 dimensions:3 spatial + 1 time(like).
    Discard or neglect the time ,and what are you left with is...
    Math has no problem with it.
    But physics...
     
  15. Mar 16, 2007 #14
    Note that the time axis in space-time is not the same thing as the measure of an observer's proper time.
    Since an observer who applies a boost, which is a change to a diferent frame, is semi-rotated in space-time it follows that an observer's measure of time depends on the orientation towards the time axis. :smile:
     
    Last edited: Mar 16, 2007
  16. Mar 18, 2007 #15
    Time stops at c, doesnt it?
     
  17. Mar 18, 2007 #16
    If you really see from the point of view of a photon....travelling at c....it doesnt experience time
     
  18. Mar 23, 2007 #17
    In my mind, time is the aether, while space is what we measure via EMR.
     
  19. Mar 23, 2007 #18
    time at c

    Do you consider that we can not synchronize clocks that move with c?:rofl:
     
  20. Mar 23, 2007 #19
    time at c

    Do you consider that we can not synchronize clocks that move with c?:rofl:
     
  21. Mar 25, 2007 #20
    I would think that if I could hitch a ride on a photon everything would appear the same right down to our clocks, i.e.. There is nothing out there that says our visible universe could not be seen from "some" vantage point as a photon.
     
  22. Mar 25, 2007 #21
    Unsurprisingly, there've been an awful lot of responses of dubious value to your question. This is par for the course here in the relativity forum.:smile:

    However, let me add the following. Many formulations of physics exist that do not make any reference to explicit notions of "time". Perhaps the best known of all of these are those which are based upon Jacobi's interpretation of the action principle. Instead of the usual approach to action principles and their configuration spaces, Jacobi's approach seeks to describe physics in terms of geodesics on a configuration space that correspond to physical motions of constant energy. Interestingly, it turns out that this approach makes no reference whatsoever to external notions of time; indeed, time pops out of your equations as a secondary concept.

    Even more interestingly, some really cool research has been done over the past five or so years that suggests that *all* of classical physics (including Einsteinian relativity and pretty much all gauge theories) can be formulated in this timeless manner. It's a pretty hot topic at the moment in some approaches to quantum gravity since it represents perhaps the pinnacle in "relational" physics.
     
  23. Mar 27, 2007 #22
    So we measure space, and time is the aether. I don't suppose you would care to now define aether, and indicate exactly which properties of space we measure with electromagnetic radiation?
     
  24. Mar 27, 2007 #23
    I think of time as being a dimensionless point with the potential for movement, it would only have two possible movements unto itself either expand or contract. Time as dimensionless points, would fill our universe with the potential for movement. While not all points would be expanding, if the majority of these points were, we would have an expanding universe that was not limited to the speed of light but limited to the number of points and the rate at which they were expanding. When you excite one of these dimensionless points into expanding at its maximum of c while also traveling through this aether, it could be thought of as a wave, or visualized as an expanding cone. Either way you can see that what we measure with the movement of one dimensionless point just shows us the time it traveled between some point where it was excited and my detector which is a very limited view of our universe.
     
    Last edited: Mar 27, 2007
  25. Sep 23, 2011 #24
    Let me start my home brewed nonsense then. :)

    No it is not possible to have space and matter without time. Space only has meaning within time.

    The reason why space is around us is because it takes a finite amount of time for light to reach each unique point in space from us and vice versa. Space is formed through time and only exists within the context of time.

    Rather than calling it space-time, calling it time-space may be more accurate.
     
  26. Sep 23, 2011 #25
    my 2 cts: I suppose you can, but if you have space and matter without time, you cannot observe or measure anything about them; because measurements take time. :wink:
     
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