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Light has been bugging me.

  1. Jan 6, 2008 #1
    Lately, I've been reading over the theories of relativity and special relativity and the impossibility of reaching the speed of light. I found all of this fascinating, and so I kept on in my studies. I then began taking a closer look at time dilation. The theory behind time dilation , as interpreted by me, is that since light is at light speed, it is stuck in time. This bothered me further when I read that objects going at the speed of light are supposed to flatten and squish until they are infinitely thin (this was backed up by one of Einsteins equations). The point about that that bothered me, is that no two units of matter may coexist in the same space. If light its stuck in time, then the distances from "lights" point of view are null. This would mean that every photon coexists within the same space. Does that mean that there is only one photon that we all share? Or am I just missing some blatantly obvious point.
  2. jcsd
  3. Jan 6, 2008 #2


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    It seems you've missed the main point "the impossibility of reaching the speed of light". No material body will ever be observed to reach the speed of light from any frame of reference. All matter will appear to be travelling at v < c, and light will always be travelling at c from every point of view.

    Things do look squished from a moving frame, but never 'infinitely' thin.

    What does this mean ? On reflection, I know that it is meaningless, so no need to explain.

    I suggest you read through some of the threads in the forum where these issues are discussed. You've jumped to some weird conclusions.
  4. Jan 6, 2008 #3


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    Light does not have a "point of view" nor "fframe of reference"- so the rest of what you say is moot.
  5. Jan 6, 2008 #4


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    That's not entirely true. The particles that matter is typically comprised of, called fermions, must obey the Pauli Exclusion Principle, which means they cannot have the same quantum state. These particles have half integer spin (1/2,3/2, etc)

    There is another kind of particle, called a boson, and two bosons may indeed occupy the same quantum state. Photons happen to be bosons, and so there is no worry about them occupying the same space. Bosons have integer spin.

    (Furthermore, composites of fermions can be bosons; for instance, atoms, though they are made of fermions, can be bosons, which is why they can form Bose-Einstein Condensates.)
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