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Ridiculous to think that light is the only static

  1. Jun 22, 2004 #1
    This isnt a statement or theory, i simply need help on understanding a topic. Light particles are always travelling at the same speed relative to you, even if you are moving, is it ridiculous to think that light is the only static thing in the universe and it is light that we move towards. Maybe someone could help me understand why light does this or explain why my ponderring is wrong. I havent developped my static light idea so go easy on me with the criticism.
    Last edited: Jun 22, 2004
  2. jcsd
  3. Jun 22, 2004 #2
    I wouldn't say that light is static, but neither it has a "speed". I think that what we call speed is more likely a property of light. It's like when you think about electric charge (or other forces as well): you could wonder "Why don't electrons exhaust their charge? Where is their source ?" Even in this case I think about forces as properties of the related particles.

    Anyway it's only from the point of view of a photon that things get "weird": to it time is frozen, but it interacts anyway...
  4. Jun 22, 2004 #3
    I was watching an internet live feed from CERN when this theoretical physicist explained that Photons could be inifnatly crammed into a box without filling it. Yet dont photons have a mass or volume like other particles?
    Is space-time itself just photons, my mind is often a blur when trying to reason with myself but it would seem appropriate that the fabric of space-time is photons, maybe someone could explain why it isnt.
  5. Jun 22, 2004 #4
    Btw, the reason i am constantly asking for answers is because of fear of making a statement that would probably be crushed by someone
  6. Jun 22, 2004 #5
    Lets say you're moving at 0.25c and a light ray comes at you from behind. Instead of thinking that the actual wavefront its moving towards you at 0.75c think that the peaks of the wave pass you more slowly. In this effect the relative frequency decreases instead of it's velocity.
  7. Jun 22, 2004 #6


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    No one can explain why light always travels at c -- it just happens to be a feature of this universe.

    And yes, you can pack an infinite number of photons into a finite volume, because photons are bosons -- there is no exclusion principle that prevents many of them from occupying the same quantum state.

    - Warren
  8. Jun 22, 2004 #7


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    No ones here to crush you. As long as your statements are factual that is :smile:
  9. Jun 23, 2004 #8


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    Light has no rest mass (although it does have energy so that it appears to have gravitational mass). As for volume, I'm not sure how one would define "volume" for any elementary particle, much less light.
  10. Jun 23, 2004 #9
    Well this is why i made that point about it being the fabric of space-time, if space time were made up of such particles as photons then there would be no volume for it, hmm i am poor at explaining myself, yet its the only way in my mind i can justify that photons can be infinatly packed into a finite amount of space.
  11. Jun 23, 2004 #10


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    You said you were thining of photons as particles. Try thinking of the photons as a collection of waves and packing them into a finite space sounds a little less absurd.
  12. Jun 23, 2004 #11
    Ahh, thanks, I was having trouble, that seems more feasible.
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