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German Physicists Claim Speed of Light Broken

Posted by ScuttleMonkey on Fri Aug 17, 2007 08:29 AM
from the don't-believe-your-optics dept.
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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  • by DigitalReverend (901909) on Friday August 17 2007, @08:32AM (#20260025)
    What are they going to do to fix it?
    • Re: (Score:3, Funny)

      by Anonymous Coward

      What are they going to do to fix it?
      They're going to issue a patch next Tuesday.
      • by x2A (858210) on Friday August 17 2007, @12:04PM (#20263655)
        I think it's along the lines that mass appears to pull things through time; objects with mass age. When energy loses its mass, it no longer ages, and is therefore travelling at speed C (to the energy, it travels instantaniously, to everything else, it will pass at the speed of light). This is what happens when you eg, charge a particle so that a photon is given off. If that photon gains mass (eg, is absorbed into matter, warming it slightly) it will be pulled through time, will begin to age, therefore will be travelling through less space per time, which is under the speed of light.

        The real twist here is that for an object to be accellerated past the speed of light, that object would actually 'see' the rest of the universe travelling backwards, and would arrive at its destination younger than it was when it left... so it'd simple appear to us as if the packet had travelling from the 'destination' to the 'source', at a speed below the speed of light... objects travelling faster than the speed of light, and objects travelling below it, appear indistinguishable to us.

        (or something like that :-p)

  • by gozar (39392) on Friday August 17 2007, @08:33AM (#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, @08:34AM (#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, @08:34AM (#20260069) Homepage
    Information on how to break the light barrier has been around for ages [dresdencodak.com].
    • by Anonymous Coward on Friday August 17 2007, @09:03AM (#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 [popularscience.co.uk]. 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, @08:35AM (#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)

      This is called the EPR paradox [wikipedia.org] 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.

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

      by Skrynkelberg (910137) on Friday August 17 2007, @08:58AM (#20260417)
      You're thinking of the EPR Paradox [wikipedia.org].

      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 [wikipedia.org].

  • Great..... (Score:5, Funny)

    by segedunum (883035) on Friday August 17 2007, @08:38AM (#20260129) Homepage
    The time barrier's been broken, so where's that damn warp drive?
  • by TyFighter (189732) on Friday August 17 2007, @08:39AM (#20260163) Homepage
    I brought enough for everyone.
  • by abionnnn (758579) on Friday August 17 2007, @08:42AM (#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, @09:04AM (#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 Intron (870560) on Friday August 17 2007, @09:58AM (#20261171)
          Suppose we put Angelina Jolie on a rocket and send her to Mars. While there, they open the envelope. Angelina instantly becomes an Oscar winner. She doesn't know it because information will take several minutes to get there, but her state changes instantly.

          I use Ms. Jolie because she is frequently mentioned as part of an "entangled pair".
          • She doesn't know it because information will take several minutes to get there, but her state changes instantly.

            Without getting bogged down in the specifics of your thought experiment:
            According to General Relativity, her state does not change "instantly".
            According to Quantum Mechanics, her state does change "instantly".

            This is the essential problem in modern physics. General Relativity and Quantum Mechanics are, as they stand, in contradiction with one another.
    • Re: (Score:3, Interesting)

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

    by vigmeister (1112659) on Friday August 17 2007, @08:46AM (#20260259)
    Something like this was claimed a while back. Is it like this guy's [wikipedia.org] 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

    Cheers!
  • Informative (Score:3, Funny)

    by daskinil (991205) on Friday August 17 2007, @08:48AM (#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.
  • by kannibul (534777) on Friday August 17 2007, @08:52AM (#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, @08:54AM (#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) <chriscapoccia@spamcop.net> on Friday August 17 2007, @08:59AM (#20260441) Homepage Journal
    does anyone know how these scientists measured time for this experiment? what sort of equipment do you use to measure picoseconds [wikipedia.org]
  • I thunk.. (Score:3, Informative)

    by toQDuj (806112) on Friday August 17 2007, @09:08AM (#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 http://www.irregularwebcomic.net/1636.html [irregularwebcomic.net]

    B.
    • 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 oh_my_080980980 (773867) on Friday August 17 2007, @09:27AM (#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.

  • C++ (Score:5, Funny)

    And lo, the greatest joke post title ever finally gets to be used!
  • by JayAEU (33022) on Friday August 17 2007, @11:12AM (#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 http://www.wissenschaft.de/wissenschaft/hintergrun d/173235.html [wissenschaft.de] and here http://en.wikipedia.org/wiki/Faster-than-light [wikipedia.org]

    There's even been coverage about his tunneling experiments occasionally in the nightly show "Space Night" broadcast on the German TV station "Bayern Alpha" http://www.br-online.de/wissen-bildung/spacenight/ [br-online.de] .

    Somehow this experiment keeps turning up now and then, causing wild speculation and discussions every time.
    • Re:Actually (Score:5, Informative)

      by brunascle (994197) on Friday August 17 2007, @08:48AM (#20260287)
      i think you're confusing quantum physics and relativity. Einsten didnt believe in, and tried to disprove, quantum physics, but i dont believe he ever questioned his own relativity theory.

      "God does not play dice" is about the inherent randomness in quantum physics.
    • Re: (Score:3, Informative)

      "Einstein died thinking his theory was the "dumbest thing since ...I do remember his "God does not play dice" statement."

      Actually that quote is from a letter he wrote to Max Born [wikipedia.org] about his distrust of the theory of quantum mechanics, not his own theory of relativity. Here [wikiquote.org] is the actual quote:

      Quantum mechanics is certainly imposing. But an inner voice tells me that it is not yet the real thing. The theory says a lot, but does not really bring us any closer to the secret of the Old One. I, at any rate, am c

      • Re:Actually (Score:5, Insightful)

        by kebes (861706) on Friday August 17 2007, @09:22AM (#20260703) Journal
        As an aside, I find it interesting how different people interpret Einstein's famous stance on Quantum Mechanics. As indicated in that quote, Einstein felt that Quantum Mechanics was fundamentally incomplete, and was not an accurate representation of reality. Now, many people point to Einstein's disbelief to support their own arguments that Quantum Mechanics is wrong. Thus their argument is: "See! If a smart guy like Einstein says it's wrong, then it's probably wrong!"

        However Einstein himself, over his entire life, was never able to disprove Quantum Mechanics, despite many attempts. All the thought experiments and physical experiments he proposed instead bolstered the case of Quantum Mechanics, since the predictions of the theory were verified time and again. In the years since Einstein's death, the case has only gotten stronger: Quantum Mechanics is now one of the most thoroughly and rigorously verified theories we have (along with relativity, of course).

        So, the alternate interpretation of Einstein stance is: "See! Even a really smart guy like Einstein is wrong sometimes!" Just because Einstein "felt" that Quantum Mechanics was wrong does not make it so. In this case, his intuition seemingly failed him.

        (Incidentally, one thing we do know is that there is a mismatch between our two best theories: quantum mechanics and relativity. It's not at all obvious how to reconcile them, and it is likely that they are both "wrong" in the sense that they both need to be modified to be united into a single coherent theory. However the aspects of Quantum Mechanics that Einstein didn't like (nonlocality, randomness, etc.) are firmly established and are probably not going to be "undone" by even a unified theory.)
        • Re: (Score:3, Interesting)

          However the aspects of Quantum Mechanics that Einstein didn't like (nonlocality, randomness, etc.) are firmly established and are probably not going to be "undone" by even a unified theory.

          Randomness established? What experiment could possibly establish randomness? I'm with Einstein on that one.
    • Re:Actually (Score:5, Funny)

      by Nilych (959204) on Friday August 17 2007, @09:02AM (#20260471)
      I liked Niels Bohr's response to Einstein's comment:

      "Einstein, stop telling God what to do."
    • Idiocy (Score:4, Insightful)

      by InvisblePinkUnicorn (1126837) on Friday August 17 2007, @08:53AM (#20260353)
      Light is light, no matter the frequency. I think when you say "light", you're trying to refer to light in the visible part of the spectrum.

      The summary does however call photons "energetic packets of light" when I think they're trying to say "packets of energy".
      • Since time travel is still an uncertain phenomenon, unless we scour the entire universe for Einstein, isn't he still in a state of both dead AND alive at the same time? Then again, Einstein was no cat.

        Cheers!
    • by eyebits (649032) on Friday August 17 2007, @08:56AM (#20260393)
      Photons do not have mass.

      From: http://imagine.gsfc.nasa.gov/docs/ask_astro/answer s/960731.html [nasa.gov]

      The Question
      (Submitted July 31, 1996)

      Do photons have mass? Because the equations E=mc2, and E=hf, imply that m=hf/c2 . Is it so?

      The Answer
      No, photons do not have mass, but they do have momentum. The proper, general equation to use is E2 = m2c4 + p2c2 So in the case of a photon, m=0 so E = pc or p = E/c. On the other hand, for a particle with mass m at rest (i.e., p = 0), you get back the famous E = mc2.
    • by Mr. Underbridge (666784) on Friday August 17 2007, @09:03AM (#20260487)

      then how does a photon, WHICH HAS VOLUME AND MASS, travel at the speed of light without having the same mass/energy as the whole of the universe?

      Well, you've proven one theory of mine - any postulate typed in uppercase is guaranteed to be incorrect. ;)

        • It's sorta like this (Score:5, Informative)

          by Moraelin (679338) on Friday August 17 2007, @09:50AM (#20261099) Journal
          It's sorta like this:

          1. First of all, the somewhat inaccurare version Newtonian version: when you calculate the acceleration of a small body in the gravity field of another body, the small body's mass cancels itself out.

          I mean, the force is: F= G * M * m / d^2

          The small body's acceleration therefore is: a = F / m = G * M / d^2

          You'll notice that the small body's mass isn't present at all in the acceleration, which in this case is also determining the curvature of the trajectory. Or to put it otherwise, a 1g thumb tack will fly in the exact same orbit as a thousand ton Goa'uld pyramid. As you make mass smaller and smaller, in other words take a limit when mass -> 0, well, the trajectory still stays curved.

          2. Actually, in a perverse way, you are right that Newtonian mechanics should not apply to light, and they don't: if you apply Newtonian mechanics to light, the predicted deflection of light is only half the deflection actually observed. So light does act funnily in a gravity well.

          Light's curvature in a gravity well is only explained right by Einstein's general relativity. There gravity is just the observed consequence of a distortion of space itself. The presence of a mass there distorts space. The usual analogy is that it's like having a horizontal rubber sheet and placing a steel ball upon it. You'll get an indentation in the sheet. The effects on other nearby bodies, or on their movement, is basically just the consequence of that distortion of space.

          And so it is with light too. It's not as much that newtonian gravity pulls it, as just that it's moving through a warped piece of space.

          3. Generally, don't try to apply your RL intuition and experience to relativistic or quantum phenomena, it tends to just fail spectacularly :)