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Breaking The Speed Of Light!

  1. Jun 15, 2005 #1
    i just heard that some outlandish men in germany transmitted music faster than light. is this true?
     
  2. jcsd
  3. Jun 15, 2005 #2
    Music travels at the speed of sound, so I'm gonna say no just on that basis. That fails on many more levels though.
     
  4. Jun 15, 2005 #3

    Claude Bile

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    The music obviously isn't in sound form, it is probably transmitted optically. I seem to recall reading something similar in New Scientist magazine, will see if I can find any verification of this.

    Claude.
     
  5. Jun 15, 2005 #4
    I also remember reading something about this too. I don't remember where, and I think it has something to do with quantum tunneling, but I can't be certain.
     
  6. Jun 15, 2005 #5
    I don't know, but when I think music, I think a series of audible notes, but thats just me. :uhh:
     
  7. Jun 16, 2005 #6
    No, if it was, everyone and their pet rocks would know about it.

    It probably is just some technicality that makes it technically faster than light in some way but in reality it's not.
     
  8. Jun 16, 2005 #7

    JamesU

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    if they sent it faster than the speed of light, then how could they detect it? it would've gone back in time, thus never reaching it's destination point (while the experament was taking place) :wink: :biggrin:
     
  9. Jun 16, 2005 #8

    Gza

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    I think you are referring to the group velocity of the wavepacket comprised of the component waves of the signal to be greater than the speed of light. This has been documented already, but doesn't violate relativity.
     
  10. Jun 16, 2005 #9

    Lisa!

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    I don't think that this news would be right.I heard about breaking light speed a lot but it's not been true.I think if it happens 1 day physicists will be :cry: :rofl:
     
  11. Jun 16, 2005 #10
    the day someone even reaches the speed of light will be the day people will know how to divide by 0 :rolleyes:
     
  12. Jun 16, 2005 #11

    Danger

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    Are you familiar with the concept that 'optically' means 'by light'? Light does not under any circumstances go faster than itself.
    On the other hand, it has been documented for decades that physical objects travel as fast as or faster than light. The specific rule in relativity theory is that no object with mass can travel at the speed of light in vacuum.
    Massive objects can exceed light speed in vacuum, as long as that is their lowest boundary. That's what 'tachyons' are about. Conversely, massive objects can exceed light speed in a refractive medium without violating the laws. 'Cherenkov radiation', for instance, is the bluish glow that you see in a uranium storage pool and is caused by neutrons and some other particles going faster than light speed in water.
     
  13. Jun 16, 2005 #12

    Lisa!

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    You're so optimistic!
     
  14. Jun 17, 2005 #13

    ZapperZ

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    However, let's not forget that "tachyons" are not one of those that have been "documented". They have not been detected, much less verified to be superluminal.

    Zz.
     
  15. Jun 17, 2005 #14

    ZapperZ

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    I didn't stick my nose into this thread before this because I HATE question like this (was that a strong-enough denounciation?). :)

    "I just heard" or "I read somewhere" shouldn't be used anymore, at least not on PF physics section. If one demands a thorough, coherent, and valid reply, then the question should also, at the very least, not be ambiguous. You must always cite the source of where you got such a thing. This allows the rest of us to (i) double check if you read it correctly and not simply misinterpret what you read (a common occurence); (ii) to address accurately what is being said or written.

    The only possible scenario that I can think of for such a question was the situation a while back (yes, this is outdated) that someone claiming to have transmitted a radio signal via tunneling through a medium of a piece of Mozart symphony, and comparing it with the signal that just went through air. The claim then was that the signal that tunnneled through travelled faster.

    This is nothing new. There has been repeated claims that tunneling could be a superluminal process. It has not been verified, and the claim made above is still under dispute.

    Of course, this could all be moot if the OP isn't refering to this particular experiment.

    Zz.
     
    Last edited: Jun 17, 2005
  16. Jun 17, 2005 #15

    Danger

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    True that they haven't been documented, but their existence is allowed for in Einstein's formulae. I haven't heard anything about them being ruled out by any QM theories, but that's a field that I can't keep up with very well. The last that I read about them, people were still trying to figure out some way to detect them if they're there. As for the superluminosity, that's why they're called 'tachyons'. If they're slower than light, they'd be something else.
     
  17. Jun 17, 2005 #16

    jma2001

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    Yes, I believe that is exactly what the OP was referring to, I am surprised no one has come up with the name yet. It is Guenter Nimtz of Cologne University, here is a page describing his "superluminal tunneling device":
    http://online.itp.ucsb.edu/online/qo02/nimtz/

    He gained some notoriety a few years back when he was featured on the television program NOVA:
    http://www.pbs.org/wgbh/nova/transcripts/2612time.html

    Here is an article by John G. Cramer that explains why this, and similar devices, do not violate causality. It has to do with the distinction between the group velocity and the front velocity of a light wave:
    http://www.npl.washington.edu/AV/altvw105.html
     
  18. Jun 17, 2005 #17
    its possible..its an analog signal and it can be transformed to electromagnetic wave signal, NOT NECCESSARILY an optical one but can be any other form as we know there are many types of EM waves, light being one of those.In fact we dont transmit it as sound wave for long distance as it is liable to noise...we know that C< Vp i,e phase velocity (wave trains)but it cant be used for transmission of message.I am sure in air its impossible to exceed speed of light but in some other medium its possible to send msg faster than light as in the medium the speed of light gets reduced to c/n..n is R.I of the medium ...
     
  19. Jun 17, 2005 #18
    :bugeye: tunneling is a total diff concept and you cant correlate it with this...it refers to alpha emission from nucleus!!! I will die if i hear this once more :smile:
     
  20. Jun 17, 2005 #19
    im realistic, seeing as in relativity [tex]\gamma[/tex] is given by

    [tex]\gamma = \frac{1}{\sqrt{1 - \frac{v^2}{c^2}}}[/tex]

    if anything reaches the speed of light either relativity is incorrect or we can now divide by 0 :approve:
     
  21. Jun 17, 2005 #20

    ZapperZ

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    Well, I hope you don't "die" from hearing this, but I think I may have misunderstood what you have said here. Are you implying that "tunneling" concept is only restricted to "alpha emission from nucleus", and that photon tunneling or any other form of tunneling just doesn't exist?

    Zz.
     
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