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Science Technology

German Physicists Claim Speed of Light Broken 429

Byzanthy writes "Two German physicists claim to have broken the speed of light by using 'microwave photons.' According to Einstein's special theory of relativity, it would require an infinite amount of energy to accelerate any object beyond the speed of light. However, Dr Gunter Nimtz and Dr Alfons Stahlhofen, of the University of Koblenz, say they did it by using a phenomenon known as quantum tunneling. The pair say they have conducted an experiment in which microwave photons — energetic packets of light — traveled 'instantaneously' between a pair of prisms that had been moved up to 3ft apart." New Scientist, however, is running an article that suggests Einstein can rest easy. Aephraim Steinberg, a quantum optics expert at the University of Toronto, explains that the German physicist's results aren't necessarily wrong, they are just being interpreted incorrectly.
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German Physicists Claim Speed of Light Broken

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  • by DigitalReverend ( 901909 ) on Friday August 17, 2007 @09:32AM (#20260025)
    What are they going to do to fix it?
  • by gozar ( 39392 ) on Friday August 17, 2007 @09:33AM (#20260041) Homepage
    186,000 miles per second, it's not just a good idea, it's the law.
  • by nbannerman ( 974715 ) on Friday August 17, 2007 @09:34AM (#20260057)
    How am I supposed to welcome our new microwave-photon overlords if they've already arrived?
  • How quaint (Score:3, Funny)

    by Verteiron ( 224042 ) on Friday August 17, 2007 @09:34AM (#20260069) Homepage
    Information on how to break the light barrier has been around for ages [].
    • by Anonymous Coward on Friday August 17, 2007 @10:03AM (#20260489)
      Apparently, Chris Lee has read the current paper, but Prof. Nimtz isn't new to the field of faster then light transmission, he demonstrated this a few years ago with a mozart symphony in a barrier shaped like fig. a in this article on popular science []. The results experiment have been confirmed by others, showing that the signal travels at about 4.7c in the narrow section of the barrier, if I am not mistaken. Chris Lee appears to have some understanding of the basics, but he tries to argue against the new paper with some handwaving and appealing to intuition, however both are quite useless in the field of quantum mechanics.
  • quantum spin (Score:3, Interesting)

    by randuev ( 1032770 ) on Friday August 17, 2007 @09:35AM (#20260087)
    Doesn't quantum changing of spin happen faster than light would travel between two points? Does teleportation actually breaking speed of light? Otherwise why would it be called teleportation if it's just moving things (really) fast?
    • Re: (Score:3, Informative)

      by vigmeister ( 1112659 )
      This is called the EPR paradox [] and IIRC it was forwarded by Einstein himself to demostrate the quantum physics yielded BS results. I don't think it is now considered a real paradox since information still cannot be transmitted faster than light.

    • Re:quantum spin (Score:4, Informative)

      by Skrynkelberg ( 910137 ) on Friday August 17, 2007 @09:58AM (#20260417)
      You're thinking of the EPR Paradox [].

      Simplified, when you have two entangled electrons and measure the spin along an axis of the first, the second one immediately takes on the opposite spin of the first.

      But you don't know what spin you are going to get by measuring the electron; because it is made of two entangled wavefunctions it's pure chance which one is going to show up. Thus, you have no control over which spin the second electron has, and thus you can't transmit any information using this phenomena.

      However, you DO know the spin of the second electron, a fact that can be used. For example, you can create potentially unbreakable ciphers using Quantum Cryptography [].

      • But what happens when you have to entangled electron and you measure the position of the first? Then the position of the second is no longer uncertain. So if you have two streams of electrons, split off after passing through the ubiquitous double-slit, with each electron in one stream having an entangled body in another, then once you start measuring one of these, the second stream will no longer form an interference pattern. I think a few months ago there was a story about this kind of setup being made
      • Re: (Score:3, Interesting)

        by Anonymous Coward

        Simplified, when you have two entangled electrons and measure the spin along an axis of the first, the second one immediately takes on the opposite spin of the first.

        Well, the second one immediately always had the opposite spin to the first. The wierd thing is that if you had measure spin of the first along a different axis, the second would instead have always had opposite spin to that instead, since when you measure a spin you either get an integer multiple of hbar or nowt, and whatever you measure it as becomes reality thenceforth.

        Which is all decidedly strange. It's almost like we're living in an approximation running on a superscalar processor...

      • Re: (Score:3, Interesting)

        by einhverfr ( 238914 )
        Personally, I think that most Quantum Physics seems to conflate observation with reentanglement.

        However, this hypothesis is actually partially testible because it implies that, if we can separate quantum particles without entangling them based on forcing them to choose paths based on states, that this should break the entanglement. I.e. if an entangled photon pair is forced to choose different fiberoptic paths based on differences in the refractive index of a part of the fiber optic cable, and this is depe
  • Great..... (Score:5, Funny)

    by segedunum ( 883035 ) on Friday August 17, 2007 @09:38AM (#20260129)
    The time barrier's been broken, so where's that damn warp drive?
  • by TyFighter ( 189732 ) on Friday August 17, 2007 @09:39AM (#20260163) Homepage
    I brought enough for everyone.
  • by abionnnn ( 758579 ) on Friday August 17, 2007 @09:42AM (#20260199)
    Guys come out confusing group velocity with the speed of light, from the very first equation I am beginning to suspect that it is the case. I have read the paper, and must question their conclusion as their setup is not entirely clear. This said, everybody loves surprises. Yes, IAAP.
    • by kebes ( 861706 ) on Friday August 17, 2007 @10:04AM (#20260497) Journal
      Indeed. Now, I won't say with certainty that this present claim is wrong... but we've seen so many "speed of light broken!" reports over the years that I'm not going to get too excited. Typically, when people think they have seen a speed-of-light violation, they are actually reporting on one of two well-established phenomena:

      1. Group velocity versus speed-of-light. Basically, relativity states that no individual photon can travel faster than c. However a collection of photons interfere to form a beam or a pulse with some kind of shape. You can arrange your experiment so that the envelope of the pulse travels at some velocity (faster than light, slower than light, etc.) but the individual photons are still always traveling at exactly c.

      2. Quantum instantaneousness. Two particles can be put into a quantum entanglement, such that their states depend on one another, even though they have not 'picked' a particular state yet. You can separate the two particles (even by a huge distance), collapse one particle into a state and the other particle collapses instantaneously into the corresponding state. This instantaneous effect seems to violate the light-speed rule. However because the experimenter cannot control the state which is selected upon collapse, no "information" is actually transmitted from one location to the other.

      Importantly, both 1. and 2. involve emergent effects that a human may characterize as "faster than light"--but no information, and no energy, was transmitted faster than light-speed. (And, to be clear, relativity states that energy and hence information cannot travel faster than light. Emergent phenomena can travel at arbitrary speed. In fact in relativity spacetime itself can, theoretically, expand faster than light, but you still can't send signals from one location of spacetime to another at greater than c.)

      From the descriptions, it really does sound that these researchers are merely committing one of those two classic fallacies (or maybe a novel combination of the two?). Now, assuming that these researchers are not novices, I find it hard to believe that they would commit such classic mistakes. So in this case it might be a subtle point to prove that relativity is not disproved, but my assumption would be that they have made a mistake somewhere.

      I don't mean to dismiss these results, and new science certainly comes from violations of established science. However relativity is so well-established at this point that making the extraordinary claim "we've violated relativity" is going to require exhaustive verification.
      • by rhakka ( 224319 )
        I have to ask: why is it that because the information is not determined by a researched and then transmitted, that it is not information?

        It would seem to me... as an absolute lay person, of course... that information is being transmitted in the quantum entanglement example, it's simply not USEFUL or controlled information to us. But obviously, somehow the remote particle has to be "told" it's time to change in some way when the first particle changes. Whatever mechanism transmits or conducts that "signal
    • Re: (Score:3, Interesting)

      by Hoi Polloi ( 522990 )
      This is proof of the power of peer review.
  • Incredible? (Score:5, Informative)

    by vigmeister ( 1112659 ) on Friday August 17, 2007 @09:46AM (#20260259)
    Something like this was claimed a while back. Is it like this guy's [] experiment where although an adge of a light pulse travelled faster than light, information still could not be transmitted faster than light?

    Not discrediting the achievement. This will help us clarify current theories regarding speed limits and stuffz

  • Informative (Score:3, Funny)

    by daskinil ( 991205 ) on Friday August 17, 2007 @09:48AM (#20260297)
    I'm glad there was a post today to tell me the speed of light isn't broken. I need a reminder every once in a while.
  • How many German physicists does it take to change a broken speed of light? Answers below:
    • by SQLGuru ( 980662 )
      None.....once it was broken it went back in time to a point where it wasn't.......


  • Hold on a second here... They say that they've exceeded the speed of light with (drumroll please) Photons! But, wait a minute, isn't that light? However fast those photons were going, *is* the speed of light. It's just that they've discovered that all the rest of the photons in the universe just really aren't giving it their all.

    (by the way, this is a joke. I know what they mean, it just seems funny to me.)
    • I think the photons were traveling normally, it's just that the rest of the universe suddenly moved backwards relative to them. That is obviously the simplest answer.
  • by kannibul ( 534777 ) on Friday August 17, 2007 @09:52AM (#20260351)
    We shall call this new Technology:

    Way to go Anywhere Really Phast

    Or WARP

  • Nothing new.. (Score:4, Interesting)

    by Araxen ( 561411 ) on Friday August 17, 2007 @09:54AM (#20260361)
    The effect they measured is not new. As they described correctly, the waves are evanescent modes. The thing about these modes is that they do not possess a velocity with a real number value; the index of refraction is effectively imaginary. Imaginary in the sense that you need to consider the square root of a negative number. The imaginary velocity means the modes decay away from the surface (of the prism in this case). But if you have another prism close enough, it can pick up some of the evanescent mode and convert it back to real propagating light (which travels at real light speed).

    Since imaginary speed waves die out over long distances, for which we do need "faster than light" speed, we will not be able to use this effect.
  • "Aephraim Steinberg, a quantum optics expert at the University of Toronto ..."

    Blame CANADA!

    From the press statement:

    The McKenzie Brothers explain Nimtz and Stahlhofen's observations by way of analogy with a 20-car train departing Chicago for New York with 100 cases of 24 Molsons Beer ("two-fours" in Kanuck-speak). The stopwatch starts when the centre of the train leaves the station, but the person holding the stopwatch drinks a case of 24 at each stop. So when the train arrives in New York, now comprising only two cases of beer, the person holding the stopwatch wakes up from his drunken stupor, doesn't remember a thing for the last 23 hours, can't find the stopwatch (he sold it to someone to stake him the last 2 cases) and now claims the trip was "instantaneous" although the train itself hasn't exceeded its reported speed.

    And there you have it - The McKenzie Brothers' explanation... Beer DOES affect relativity, in a relative sort of way. I guess.

  • by capoccia ( 312092 ) on Friday August 17, 2007 @09:59AM (#20260441) Journal
    does anyone know how these scientists measured time for this experiment? what sort of equipment do you use to measure picoseconds []
    • You don't need to measure time to measure speed. Interference patterns, diffraction etc...serve well for the purposes of the experiment.
  • until I changed my mind and as I typed my scathing flammage of the Germans, I was able to turn on my microwave photon gun and correct my email to a glowing review of these brilliant scientists who have clearly figured out a way to live outside the laws of physics.

    And now I turn off my microwave photon gun set to "drippy irony".


  • I thunk.. (Score:3, Informative)

    by toQDuj ( 806112 ) on Friday August 17, 2007 @10:08AM (#20260539) Homepage Journal
    I thought that something travelling at exactly the speed of light required infinite amounts of energy. No-one said anything about more than the speed of light.

    Check out what happens when X-Rays pass the speed of "light" in water. check out Cherenkov radiation. Irregularwebcomic has a good explanation []

    • Re: (Score:3, Informative)

      It takes infinite amount of energy to accelerate something to the speed of light. It's theoretically possible for something to travel faster than light if it somehow had just popped into existence at that speed (How that would happen I have no idea).

      As for Cherenkov radiation, the speed of light is only constant inside a vacuum.
      • by toQDuj ( 806112 )
        Yes, but cherenkov radiation shows you what happens if a photon happens to "pop into existence" in a medium in which the "speed of light" is lower than the photon speed.

    • Re: (Score:3, Informative)

      by Guppy06 ( 410832 )
      "I thought that something travelling at exactly the speed of light required infinite amounts of energy. No-one said anything about more than the speed of light."

      It takes an infinite amount of energy to get something with real mass (tardyons) to reach the speed of light in a vacuum. Photons (luxons) do it by not having any real mass, only momentum. And, looking strictly at the math of special relativity, it would also require infinite energy for something with imaginary mass (tachyons) to slow down to the
  • They broke it because of Global Warming... the whole world is out of whack... we need a new science... w/ proven results... ...results that are quantifiable... solid... not subject to "misinterpretation" ... non of this crap that we've gotten so far... what has science given us already... geesh.
  • by oh_my_080980980 ( 773867 ) on Friday August 17, 2007 @10:27AM (#20260785)
    It just goes to show that journalists have a hard time reporting science.

    The Speed of Light limitation is in regards to Matter, i.e. something with Mass. A Photon does not have mass. The component is acceleration! You cannot accelerate matter faster than the speed of light. The reason being as you begin to approach the speed of light, the object in question begins to increase in mass. Thus you need increasingly more energy to propel the object. More energy, continues to increase the mass of the object.

    However there is no law against objects that already travel faster than the speed of light. For example, Tachyons. Hypothetical particles that travel faster than the speed of light. However they have never been found.

    So a Photon can travel faster than itself - i.e. speed of light because it has no mass. Interesting. The explanation of why it's wrong doesn't jive. The data still prove it got there faster than it should.

    Theoretical Physicists have a hard time with Experimental Physicists, mainly because experimental physicists have data to backup the arguments.

    • Re: (Score:2, Insightful)

      by manowar821 ( 986185 )
      You're not getting it. This is quantum mechanics/physics, not conventional.

      They're using quantum tunneling to change the photons position rather than making it "travel" faster than light moves on its own. The photons in this experiment are not "traveling" in our definition of the word, they're leaving regular space and instantly appearing somewhere else. If the particles/matter we wish to transport can leave conventional space, they no longer need to follow the rules that state "matter with mass cannot m
  • While I'm sure there will be the prerequisite warp drive/time travel jokes about this, I think the most interesting aspect lies in potential applications to communications and computing. The potential of quantum computers is already quite impressive, but imagine coupling that with the ability to design a system without concern about the physical proximity of some components. Imagine being able to build a planetary computer capable of answering the question of life the universe and .... everything! Planetary
  • Clearly this is the classic group velocity vs. velocity error again. And I don't even know what that means.
  • C++ (Score:5, Funny)

    And lo, the greatest joke post title ever finally gets to be used!
  • I'm a n00b, or a non-quantum guy. So this may be stupid.

    If you have a light which is traveling faster than the speed of light, then isn't there a simple test that can be done to determine if this is actually happening or not? Arrange the light source and a viewer at a distance apart where the speed of light can be empirically measured. Maybe 2 light second apart, so 599584916m apart. Have the viewer remotely start the light source with something such as a laser. If the viewer can see the light turn on
    • Re: (Score:3, Informative)

      by udippel ( 562132 )
      I'm a n00b, or a non-quantum guy. So this may be stupid.

      Don't worry. You're in /. Here we all are n00b, non-quantum or simply stupid. Welcome to the club.

      Galileo proposed quite exactly what you do: uncover a lantern (or better two) postioned on two hilltops.
      599584916m, though, made me smile. 599584 km and 916 m isn't quite that simple.
      And now to the core: you didn't read the article, did you ? They never suggested what you propose. They simply 'bridged' a distance of less than 1 m. But what they observed, w
  • by JayAEU ( 33022 ) on Friday August 17, 2007 @12:12PM (#20262467)
    I'm not sure whether anybody is aware of it, but this really is old news. Ten(!) years ago, Dr. Nimtz published an experiment on how to tunnel data (specifically Mozart's symphony) at higher speeds than light. Read about it (in German) here d/173235.html [] and here []

    There's even been coverage about his tunneling experiments occasionally in the nightly show "Space Night" broadcast on the German TV station "Bayern Alpha" [] .

    Somehow this experiment keeps turning up now and then, causing wild speculation and discussions every time.

Don't tell me how hard you work. Tell me how much you get done. -- James J. Ling