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Instantaneous Travel

  1. Dec 2, 2005 #1
    Please fogive any ignorance I may have of this subject, I am not a physicist :), I did however take a physics class in college.

    In that class, I learned that distance=rate of travel/time taken to complete the journey.

    One thing I've always wondered about that is, say that it is possible (somehow) for an object to move from point A to point B INSTANTANEOUSLY (Time=0), what than is the distance between points A and B?
     
  2. jcsd
  3. Dec 2, 2005 #2
    no its impossible, nothing with mass can move at the speed of light (or faster than the speed of light).
     
  4. Dec 2, 2005 #3
    Lets say it is possible :) (I dunno, maybe a massless object...)
     
  5. Dec 2, 2005 #4
    wow. Ive never heard that question before. Emm according to current physical laws, it is not possible to travel faster than the speed of light, so nothing can travel any non-zero distances instantaneously. (That's special relativity for you). Annoyingly Quantum mechanics tells us you cant be sure if something is stationary (Heisenberg is to blame for that with his uncertainty principle) and so if we limit ourselves to a physics discussion ermmm, oops... philosophically? mmm, well infinity cant even be discussed, and zero, well zero implies no dimension, and with no dimensions you cant measure distances, and so it seems that your question cannot be discussed neither in physics nor in philosophy. Why not apply the limits given by Einstein and the other clever people who applied them? =) hope i helped :P
     
  6. Dec 2, 2005 #5
    I have earlier discussed the same thing. the fact that you might help me is how to show a link?
    anyway what you said opposes mathematics. there cannot be discontinuity in the rate ofgrowth of something. i think the title to that post was something like discontinuities. though it is not same topic you will get your answer there.

    in short the answer is there is nosuchthing as infinite velocity. may even the bodybe massless for this case. masslesspoint comes into pictue during acceleration. so the rate of travel can neverbe infinity.
     
  7. Dec 2, 2005 #6

    Doc Al

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    As others have stated, it is an unphysical assumption to have something traveling faster than light, much less infinitely fast. But even if something did travel "instantaneously", I don't get your question. The distance between A and B could be whatever you want them to be. (In the nonphysical world of instantaneous travel, distance is irrelevant.)
     
  8. Dec 2, 2005 #7

    Danger

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    If quantum tunnelling counts as 'instantaneous' (and I'm not sure that it does), then the distance is whatever the spatial displacement of the particle is. You'll just have to alter your definition of 'distance'. Otherwise you'd be dividing infinity by zero. :bugeye:
     
  9. Dec 2, 2005 #8
    In my opinion...... I'm not a physicist, but anyway. Time could never equal 0. Even if any speed is attainable. For example, when you walk into a room and turn on the light. The movement of the switch and the light particles/waves being emmitted from the filiment are not instantaneous even though it may seem so. In movement, which distance implies, there is always time passage.
     
  10. Dec 2, 2005 #9
    Everyone who referenced Special Relativity is, of course, correct. No object with mass can reach the speed of light (definitely not infinity) and massless objects go only the speed of light .... again that is "only" 300,000 Km/sec. However, Bell's theorem and subsequent experiments indicate that there is some form of "instantaneous" interaction with the manifestations of a quanta. Not what ulnarian was looking for, probably.
     
  11. Dec 2, 2005 #10
    The distance between points A and B is the same distance between points A and B as if you had never travelled. In other words, you DON'T need to measure the time in order to measure the distance between two points.

    In this situation, you wouldn't be able to measure the rate (or velocity) of travel because it would be "instantaneous" (or the velocity would be infinitely fast) so the relationship d=vt would not be applicable. It would be as if someone "teleported" from one place to another ala Star Trek without any "movement" in between to observe.
     
  12. Dec 2, 2005 #11
    This whole idea of anything happening "instantaneously" without a time factor is flawed. At time=0 where is the object, point A or B? It would have to be both places at once. Not to mention instantaneous in which reference frame? There is no movement without time.
     
  13. Dec 2, 2005 #12
    Or both A and B would have to occupy the same space at the same time. Either way d=vt does not apply.
     
  14. Dec 8, 2005 #13
    My knowledge of physics is limited, but I'd like to know how it is possible for an object to have no mass, isnt light made of particles that move in the form of a wave? Doesn't that mean that light particles travel at the speed of light?
     
  15. Dec 8, 2005 #14
    That's just it. I just recently finished a book on Special Relativity that talked about this. I was reading a section about the life of a photon, in it's own point of view.

    The distance between the Earth and the farthest point imaginable, to the photon, is zero. There is no difference, to the photon, between these two places, because NO time elapses for it to get there. The photon is created and destroyed all at the same time. It's a bizarre notion, but I suppose that's relativity for you!

    The photons (quanta) of light do not possess mass. It would be impossible for them TO possess mass, if they wanted to travel at the speed of light. This is because, even if something has a tiny amount of mass, it will take an infinite amount of energy to accelerate a massive object to the speed of light. It just takes more and more energy, without limit, and so the speed of light will never be attained by something that possesses mass.

    Just because photons are particles does not imply that they are massive (though the large majority of particles do have mass, including other carriers like W and Z bosons, which carry the electroweak force.)
     
    Last edited: Dec 8, 2005
  16. Dec 8, 2005 #15

    Danger

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    Macca, there's a very nice thread just around the neighbourhood of this one that deals with the issue of light wave/particle duality (there isn't really such a thing). It will help alleviate your confusion regarding the matter.
     
  17. Dec 12, 2005 #16
    If t = 0 then this can not be called a 'travel' IMHO. How do you define 'travel' or 'transportation'? And it also means to me that being at two observable places simultaneously. This is not travel also. But if you say that t->0 then v->\infty implies v > c ( speed of light ) Which is not physical atm.
     
  18. Dec 12, 2005 #17

    Danger

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    Huh? :confused:
     
  19. Jan 30, 2012 #18
    As seen in these replies, all are limited in their response by what they have been taught. The only limits in this universe are self imposed by ourselves. Once we throw out all commonality and narrow boxed thinking, all things become possible. EVERYTHING is a possibility if we only strive to believe it possible. Chilkdren are a perfect example. Why is it that very young children have the abiality to learn anything at all ? Our brains are infinite in what they can understand if we only stop saying something isn't possible and expect all things to BE possible and therefore never give up the search for the way to make it happen. Believe that everything is possible my friends and it WILL happen....we just haven't found the answers yet.....
     
  20. Jan 30, 2012 #19
    I should stress it's not possible to "accelerate" from point A to point B faster than light, but there is nothing saying that the probability of an object cannot correlate to a distance larger than it would take light to travel (i.e. entanglement, quantum mechanics).
     
  21. Jan 31, 2012 #20
    If I'm not mistaken there are no laws governing how fast space itself can move. Especially considering that the universe itself expanded at FTL. Sooo 'in theory' if one knew how to manipulate the fabric of space it could be possible to travel almost 'instantaneous'.
     
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