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Why Are We Living In A Prison Of Light ?

  1. Aug 16, 2005 #1
    Relativity has set an upper limit for all speeds , the speed of light . But the problem we can not perceive any thing going greater than the speed of light , that's our vision limit neither can we experiment with . If superstring theory predicts a universe with ten dimensions and we are only experiencing four including time . Can't the same apply for speed ? . That's we cannot go beyond our senses capability . Could'nt there be things going faster than the speed of light that we cannot see ?.
  2. jcsd
  3. Aug 16, 2005 #2


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    The speed limitation is not like the dimension question. String physicists found they needed the extra dimensions and since we don't see any, they had to hide them, which they did by curling them up tinier than fundamental particles. But the relativity speed limit arises out of basic physics; it is a conclusion not a finesse.

    Nobody can say what the physics of the far future may be like, but relativity and its speed limit have passed an enormous number of physical tests; they are the basis of all the atom smashers, and those machines wouldn't work if the facts of relativity weren't what they are.
  4. Aug 16, 2005 #3


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    Also, traveling faster than the speed of light would not preclude us from seeing an object any more than traveling faster than the speed of sound precludes us from hearing it.
  5. Aug 16, 2005 #4
    How can you hear a sound you are moving faster than ; it would'nt catch up with you ? .
  6. Aug 16, 2005 #5
    How can you hear a sound you are moving faster than ?, it would'nt catch up with you.
  7. Aug 16, 2005 #6


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    What if you go towards the sounds source? You'll hear it...
  8. Aug 17, 2005 #7
    I am not sure about that . But in the case if a source is travelling toward you with a speed exceeding the speed of light .By the time you see it , it would have gone .
  9. Aug 17, 2005 #8


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    Ever heard a sonic boom?
  10. Aug 17, 2005 #9
    I think with sound the story is different , you will hear sound at the speed of sound whether the source is moving away from you or toward you at any whatever speed the source is moving .

    but in the case of seeing a source moving at speed greater than the speed of light , you have two cases :

    1- if the source moving away from you , you wouldn't able to see it because it is moving faster than your ability to see it .

    2- if the source moving toward you, you wouldn't able to see it either because by the time you see it , it would have gone .
  11. Aug 17, 2005 #10
  12. Sep 22, 2005 #11
    from what i hear about the speed of light, you cant travil faster than it because of time, the faster you go the slower time becomes, and time reachs stoping point at the speed of light, go faster than speed of light, and you go back in time as it was, but strange things could happen like feed back in space. lets say light was just feed back in space if you reached the speed of light, you would just turn into light! but thats just my thiory. could light be feedback in space?
  13. Sep 26, 2005 #12
    But what is time? Time is just a measure. Light is in all matter so i guess "faster" than light doesn't have any physical meaning.
  14. Sep 27, 2005 #13
    Well, I think something could travel faster than light, but the only way to know that it was at a given location is with the use of light.

    So, if particle A traveled to place B at faster than the speed of light, we would only know it got to place B once light reached that point, right?

    And since we only justify something's existence or 'truth' once it is proved, things are limited to how fast light moves, because light is the basis for proving a change?

    I know I'm not using very good physics terminology, but the logic is there I think.

    We say things can not move faster than light because to know it moved faster than light we'd have to use light to gauge or prove it, and light has its limitations, and a measurement cannot exceed its limitations. There is only one PROVEABLE maximum speed, and that is light, anything else can't be proved to have realistically moved faster, right?
  15. Sep 27, 2005 #14
    Not necessarily true. Velocity is distance/time so if you know an objects location at any 2 points and the time that it took to go between them then you may not be able to measure the object while it's moving but you can determine what it's speed was. By knowing the objects location (in relation to the observer) you can figure in any lag time needed for the light to reach you.
  16. Sep 27, 2005 #15
    How can you know the time without knowing the velocity first, because there's no way to measure the time it took to get to the second location if it moves faster than light.
    Last edited: Sep 27, 2005
  17. Sep 27, 2005 #16
    Let's say you see an object in the sky and note the time. Sometime later the same object appears at a different position and you note that time as well. Assuming that you know the distance between the two points and from yourself it's simple math to figure out how fast it had to travel to cover that distance in the given amount of time.
    If the object truly traveled FTL then it would show up in the second location first though.
    Last edited: Sep 27, 2005
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