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Quick question for a confused English major

  1. Jan 21, 2005 #1
    English Major

    Translation: Knows little to less about physics.

    However, I have a question for some of you who DO know...

    I realize that it's all theory and that we can know what happens AT the speed of light, but I'm wondering this:

    Is it possible for only one singular light particle/wave thing (photon?? see, I told you I knew nothing), travelling at the speed of light, to exist, and simply be in all places at once? This may sound inane... but if time stops relative tothe particle, then it, technically, COULD be everywhere at once, and perhaps there is only one particle in the entire universe...

    hmm... for that matter, why does it take any time, in our eyes, for light to travel anywhere? I mean, it has a speed, right? Which implies that time is NOT stopped relative to the light... or is it that it's not actually going C, because it's not in vaccuum?

    So, what part am I getting wrong, here?

  2. jcsd
  3. Jan 21, 2005 #2


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    Actually, that's not so bad. The problem is DEFINING what it means to "be in all places at once"!

    No, being in or not in vacuum has nothing to do with it. It is NOT true that light "has a speed" RELATIVE TO US "implies that time is NOT stopped relative to light". Not being light myself (there's a joke there I will NOT use!) and not moving at the speed of light, I have no idea what it would mean for time to be "stopped relative to the light" but it has nothing to do with light moving relative to us.

    So, what part am I getting wrong, here?

  4. Jan 21, 2005 #3


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    The fact that you're confued actually means you do understand the implications reasonably well. At first glance, its so cointerintuitive, it should confuse anyone who can grasp it. You've got a good start (and welcome to PF!).

    Some of the bizarreness of Quantum Mechanics may be related to the idea that light is timeless and spaceless, but in any case:
    You're having problems here because this line of reasoning does, indeed lead you to dead ends. Ie, if time is stopped for light, how can you even calculate speed from the light's frame of reference? The answer is, of course, you can't. Because of this, you can't really say light has a frame of reference of its own - there isn't much useful that can be said about it. So with that, its best to try not to think about riding along next to a beam of light just yet and think about what you really can do: travel around the world, in a plane, on a spaceship, and you'll always measure the speed of light to be C.
  5. Jan 31, 2005 #4
    Hunh... okay then. So the answer is that there is no answer. Umm... I find it odd that there isn't even a theory to try and explain this... or is there? Does anyone know of any quasi-explanation? Doesn't the fact that light has a speed present a gaping hole in the thoery itself?

    It hurts my brain. Oh well... I guess neither science nor religion can explain it all. That's where faith comes in, eh?

  6. Jan 31, 2005 #5


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    Well, the reason there's no answer because it's not a well-formed question. Technically, a photon doesn't exist in an inertial reference frame, and the physics of special relativity becomes singular at the speed of light -- distances shrink to zero, times to infinity, and so on. The mathematics of infinite quantities is actually pretty straightforward, but you won't have much luck interpreting that math to arrive at a picture of how the world looks to a photon. Our human experience is based in the world of the finite, and we just can't expect those experiences to anything like those in the world of the infinite. It's a moot point, too, since a human can't ever go the speed of light, anyway. The question simply has no answer.

    - Warren
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