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Spatial demensions are dependent on

  1. Apr 22, 2004 #1
    Spatial demensions are dependent on....

    ....the existence of a temporal demension. According to the Elegant Universe by Brian Green, the geometry of a sphere is similar to that of a flat (2D) circle in spinning on its axis at a high speed. After reading this passage, I concieved the idea concerning the [simultaneous] dependency of spatial demensions on time.
    Consider the 2D circle spinning on an axis (of course in 3D space). It forms a geometry similar to that of a sphere when it is viewed in its motion. The only way for such motion to occur, obviously, is if there is a temporal demension. Without time, there would be no motion. Therefore, the fact that an atom vibrates (Brownian motion), that is, stays in motion, can only be if there is time.
    Okay, I am now venturing on ground I am unsure of. So, to simplify my idea into a question, is it possible that all demension is a result of some rapid motion?

    thank you!!
    :confused:
     
  2. jcsd
  3. Apr 22, 2004 #2
    Temporality may just be an illusion. What we perceive to be time may just be the result of global changes of the topology of space.

    See: http://www.math.ucr.edu/home/baez/planck/planck.html

    I'm not sure exactly what you're getting at, so let me see if I've got this right. You are claiming that, in the example of the rotating disc, it is the rotation which generates the extra dimension of space so that we see a sphere.

    You mention the disc spinning on an axis in 3D space. If that's the case, you're assuming that the third spatial dimension is already there, so the rotation of the disc doesn't actually generate the third spatial dimension.
     
  4. Apr 22, 2004 #3
    Yes, the change in entropy; which is exactly what time is.

    Yes, you have grasped my idea.

    Good point! So when Brian Green specifies the aforementioned anology, what does he mean?
     
  5. Apr 22, 2004 #4
    Well, when saying that temporality may just be an illusion, I wasn't referring to entropy, but yes, it is rather interesting that entropy only works in one "direction" (as it were). I really haven't looked into that though, but I certainly should. Do you have any thoughts on it?

    I'm not sure what Greene is getting at. I actually haven't read Elegant Universe. I don't really trust popular physics books.
     
  6. Apr 23, 2004 #5
    I have found an intriguing article on what is called "The Law of Maximum Entropy". Apparently, it specifies a law which says that disorder does not necessarily have to increase; but rather, it is possible for it to minimize.

    you may view it here: http://www.entropylaw.com/thermoevolution10.html
     
  7. Apr 23, 2004 #6
    Well, entropy is independent of path. So all processes which go from state A to state B are equivalent for the purposes of thermodynamics. However, not all processes are equivalent in their rate. In other words, in going from state A to state B, we will get the same entropy change regardless of path. But the rate of entropy change as a function of time is dependent on path.

    It seems that all the article is saying is that the path of choice for a system is that which maximises the rate of entropy change as a function of time.

    Now, I'm not a physicist, so don't quote me on this, but this seems to me to be a result of the least action principle.
     
  8. Apr 24, 2004 #7
    Are you some sort of logician then? truly, you are very talented in the field. Or are you a philsopher of sorts? You seem to be very experienced in paradoxes and philosophers.

    anyway....

    So A->B=B->A and all other combinations?


    What kind of path? u mean direction? How would the path/direction change?

    Also, what is the relationship of a temporal demension and spatial demensions?
     
  9. Apr 24, 2004 #8
    This seems to suggest that the purpose of life is to be more efficient at dissipation (The purpose of life is to destroy?)

    The arguments I've read on this site are incomplete. If they could show what potentials are more efficiently minimized by an ameaba or a blade of grass, I might be convinced.
     
  10. Apr 24, 2004 #9
    Well, independence of path in entropy means that we can go from state A to state B by any means whatsoever, and this has no bearing on the states A and B. By path I loosely mean process. However, not all the processes which take us from A to B are equivalent. Some will occur faster than others. That above article seems to be claiming that the process going from state A to state B is always the fastest possible process.

    According to relativity, space and time are not mutually independent, they are inextricably linked.

    Thank you for your kind words. I am a philosophy/logic and maths major. Theoretical physics is somewhat of a "hobby" of mine.
     
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