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Special Relativity, Existence, and Big Bang

  1. Nov 9, 2007 #1
    After mulling over special relativity for a while, I have come to some conclusions that seem correct, but I don't know if I'm on the right track. I'd like to know what some of you think. Please keep in mind that I only recently started learning about relativity, so I'm somewhat of a layperson on the subject.

    I wanted to show that an observation point traveling at the speed of light would contain the entire universe... but how? Special relativity says that if an observer were to travel at the speed of light, the universe would be compressed down to an infinitely thin plane, perpendicular to the vector on which the observer is traveling. Time would stop at the observer, which means this plane would also contain an infinite amount of time (or all of time).

    Okay, so we have a plane that contains two of the four observable dimensions. What about the other two? If we open ourselves up to extra dimensions (as in superstring theory), the solution becomes simple... I think. From a perspective that includes another dimension, the position of the observer on the plane and it's vector angle have infinite possibilities. If we pay attention to just three of those possibilities, all with the same position but different vector angles, the planes would intersect at a point... the observation point. If traveling at the speed of light can compress two of our dimensions, it seems pretty likely that it can do the same on one of these "extra" dimensions (this is where the "guess" part of my idea came in). The convergence of these possibilities causes our other two observable dimensions to converge onto the observation point as well.

    If there are 11 dimensions, I suspect that they all have a different effect on each other at the speed of light, but the cumulative effect is a convergence to one infinitely small point that contains the entire universe in all dimensions. If that is true, then existence and the big bang are simply the observer slowing down from the speed of light, or perhaps a particle that is changing states from the speed of light to something less.

    But what caused that particle/observer to change states? If I were a theist, I would say God. If I were a science fiction writer, I would say that particles changes states in our universe all the time, and that a different universe exists in each changed particle (i.e. we are just a particle changing states in someone else's universe). But I'm neither, so I have no idea.

    What do you think?
  2. jcsd
  3. Nov 9, 2007 #2


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    It's not at all clear what that could mean!
    Relativity doesn't say anything of the sort! First relativity says that an "observer" can't move at the spead of light. If you want to talk about an observer moving at almost the speed of light, then relativity says that he would observe the rest of the universe as compressed, not that it would be. Time would (almost) stop for the observer which means he would not observe any motion at all.

    I don't see how one could argue that different dimensions "affect" one another at all. You seem to have jumped from a motion in one direction that affects observation in that direction only to assuming that if you add "other dimensions", those new dimensions will also be affected even though they are not the direction of motion. I see no reason for that assumption.
  4. Nov 9, 2007 #3
    I realize that. If an observation point is moving at a speed approaching the speed of light, the amount of time passing outside of that point becomes a limit approaching infinity, and the amount of space being observed would also be a limit approaching infinity.

    If this observation point were to travel at the speed of light, the space being observed would have to be infinite, and the time passing outside of that point would have to be infinite. Think of the twin paradox IF the traveler was traveling at the speed of light... the amount of time that passes for the non-traveler would have to be infinite.

    Yes, it is impossible for an observer to reach the speed of light due to the mathematical limits. But I'm trying to imagine an observation point already traveling at the speed of light. And for that to exist, it would have to be observing infinite time and infinite space... or shall we say, the entire universe.

    Yeah, I'm merely speculating at this point. I was trying to get my infinite plane to become an infinite event or point in space-time. String theory gave me the idea to consider the observer in additional dimensions.

    If I avoid talking about other dimensions, I think there's another way to think about it. The infinitely thin universe being observed would contain all of the mass in the universe (the universe moving at the speed of light from the perspective of the observer would need to have infinite mass). This thin plane would be so massive that it would have to suck in all of space-time. From another perspective, gravity would be infinite, sucking all dimensions into an infinite event.

    I'm thinking of this infinite event as the universe itself... It would have to be. And if this infinite event or an observer of the event were to slow down to anything less than the speed of light, all of space-time and existence would burst forth from that process... not unlike the Big Bang.

    I guess I'm starting to tread near Philosophy, but hey! I'm new to this and I love thinking of new ideas (at least, new to me).
    Last edited: Nov 9, 2007
  5. Nov 9, 2007 #4


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    Trying to imagine travelling at the speed of light is like trying to imagine dividing by zero. It is, for the most part, counterproductive, because division by zero is mathematically inconsistent.

    Mathematical inconsistency is bad, because of the GIGO (Garbage in, garbage out) effect - a false assumption can prove anything, true or false. The classic example is the perfectly valid (and perfectly nonsensical) proof that if 2+2=5, I am the King of England by Lewis Caroll.

    While it is outside scope of PF, being a work of fiction, you might want to consider reading "White Light" by Rudy Rucker, which imagines, in a sense, that it is possible to divide by zero (more precisely, that infinities have a physical existence). Rucker even considers travelling at the speed of light as one of the consequences via an infinite series of Lorentz boosts (and in this fictional work, infinity is something that's achievable).

    You may not get a lot out of the book if you are not a mathematician, and I suppose if you take the wrong elements of it it might confuse you (you really DO have to remmember that it's FICTION).
    Last edited: Nov 9, 2007
  6. Nov 9, 2007 #5
    I guess that's why I'm treading in the realm of Philosophy. Mathematically speaking, it is impossible to imagine traveling at the speed of light. And mathematically speaking, everything begins to break down as you get closer to the big bang. I think those two facts are tied together. You see, if you try to sum up the entire universe to one point, you have to include all possibilites and all impossibilities (as we know them) in the universe. And when you start mixing the possible with the impossible, our understanding of everything breaks down, including math.

    Maybe I'm just a wild dreamer...
  7. Nov 11, 2007 #6
    Well our CURRENT understanding of mathematics and physics that govern the universe we see today is inconsistent around the time of the big bang (shortly after) but it does't mean that all bets are off, rather that a more general theory of how stuff works exists with the time of the big bang and now as two specific cases.
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