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German Physicists Claim Speed of Light Broken
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.
What are they going to do to fix it?
I read Slashdot for the headlines, because the headlines, unlike the articles, are usually original and never duplicated
186,000 miles per second, it's not just a good idea, it's the law.
What, me worry?
How am I supposed to welcome our new microwave-photon overlords if they've already arrived?
Information on how to break the light barrier has been around for ages.
End of lesson. You may press the button.
http://arstechnica.com/news.ars/post/20070816-fast er-than-the-speed-of-light-no-i-dont-think-so.html
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?
The time barrier's been broken, so where's that damn warp drive?
I brought enough for everyone.
-tyfighter
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.
You have to walk the plank.
"Waste not one watt!" - CZ
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
Cheers!
Atheist: Buddhist in a Prius
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.
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.
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!
Atheist: Buddhist in a Prius
No it wasn't... (look up group vs phase velocity)
We shall call this new Technology:
Way to go Anywhere Really Phast
Or WARP
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".
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.
Actually that quote is from a letter he wrote to Max Born about his distrust of the theory of quantum mechanics, not his own theory of relativity. Here is the actual quote:
Insert Generic Sig Here:
Photons do not have mass.
r s/960731.html
From: http://imagine.gsfc.nasa.gov/docs/ask_astro/answe
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.
"Aephraim Steinberg, a quantum optics expert at the University of Toronto ..."
Blame CANADA!
From the press statement:
And there you have it - The McKenzie Brothers' explanation... Beer DOES affect relativity, in a relative sort of way. I guess.
does anyone know how these scientists measured time for this experiment? what sort of equipment do you use to measure picoseconds
I liked Niels Bohr's response to Einstein's comment:
"Einstein, stop telling God what to do."
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. ;)
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
B.
Every experiment which ends in a big bang is a good experiment.
Only if you're within 52 light years of him.
If you were blocking sigs, you wouldn't have to read this.
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.)
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.
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.
Randomness established? What experiment could possibly establish randomness? I'm with Einstein on that one.
Then there's Hawking: "Not only does God play dice with the universe, He sometimes throws them where you can't see them."
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
A polar bear is a cartesian bear after a coordinate transform.
And lo, the greatest joke post title ever finally gets to be used!
stuff |
As you aptly noted, I omitted the "C", which represents the Speed of Light, which was likewise absent in this case.
Thus, what appeared to be a simple gaff to the untrained eye is actually a sophisticated reference en passant.
That's my story and I'm sticking to it.
"Waste not one watt!" - CZ
How about we have one single science discussion where it does not degenerate into a political bashing session. Please. I'd love to be able to read about a cool development in science without having to read about Bush, Clinton, Republicans, Democrats, or anything other than funny "you broke it, you buy it" jokes about the subject. Let's all stop obsessing on politics for just one freaking story. Please?
A Haiku: my language choices/assembler pascal lisp c/old school programmer
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 and here http://en.wikipedia.org/wiki/Faster-than-light
/ .
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
Somehow this experiment keeps turning up now and then, causing wild speculation and discussions every time.
Welcome to Slashdot. You must be new here.
Since when does being a Socialist mean 'someone who has a different opinion than me'?
I'm a n00b, or a non-quantum guy. So this may be stupid.
/. Here we all are n00b, non-quantum or simply stupid. Welcome to the club.
Don't worry. You're in
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, was, that irrespective of that distance of up to 1 m, the light travelled in zero time. At least, they couldn't measure it. At least, it did take much less time than your 1/299792458 would require it to take.
And, they didn't observe it like for a beam that your torch would produce, but for few particles of that beam only.
Personally, I think they're nuts. They confound group and phase velocities.
Before you ask, here comes my explanation: A large group of drunkards has thrown the corks of their wine bottles into the sea, at incoming tide. The corks dance up and down on the waves; slowly attaining the beach. Then, waves break. When they do so, a whole wave front rolls over. To you, as standing on the beach, the peak of the rolling wave either spreads quickly to the left or right, depending on the incoming angle. The breaking of the in-rolling waves spreads quickly; one may as well say, that its phase instance propagates relatively fast to the left or right. If need, walk down to your next beach and observe how fast the state of the waves spread across the waves rolling ashore.
That's 'phase speed': the propagation of the same phase (rolling over).
What's that 'group speed' now ? Simply: the speed with which the corks are closing in on the beach. They're dancing up and down; the states of their phases propagate quickly. But their 'information', their physical existance, approaches the beach relatively much more slowly.
The rolling-over of the phase might propagate by several meters per second. The actual approach of the corks towards the beach can as well be as slow as a few cm per minute.
Einstein's speed of light applies to the light itself; in our example the corks. While propagation of the same phase is nothing but a maya; a virtual and artifial 'speed'.
What those chaps observe is nothing but the latter: Some phase arrives on the other side of the gap as quickly as if there was no gap at all.
That much what a stupid non-quantum n00b has to add to your implied question.
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.
:-p)
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
The revolution will not be televised... but it will have a page on Wikipedia
You know how many nightmares I've had since I was a little kid about this? Ever since I found out about time travel, my first thought is - what if people from the future are amongst us? Maybe a good portion of these scientists and other geniuses are just time travellers who blended into a point in history that they liked best and are helping shape our future into a better one than the one they came from.
Damn..I should write a book about this..
Cheers!
Atheist: Buddhist in a Prius
Photons don't have Mass because they're not Catholic.
"Ayn Rand is a bloody socialist compared to me." - Robert A. Heinlein
So THAT's how Michael Jackson did the moonwalk!
...goddamit)
(Yes, one can make a Michael Jackson joke without refering to pedophili-
I think the point of the parent poster was that if you have a theory, like quantum theory, which predicts that we will be unable to predict certain results, how could you empirically verify that theory, or at least that prediction of it? You could falsify it - by showing that we can in fact predict the results which said theory predicts we should not be able to predict - but just showing over and over that we keep failing to make successful predictions does not establish that such predictions are impossible, and thus does not verify the prediction of our theory that such predictions are impossible. Consider a formally similar "theory" from a very different camp: that certain phenomena do not have natural causes, i.e. they are miracles. While you can falsify this (by showing a natural cause), you can never verify it; at best, all you can show that we still can't tell what the natural causes for those phenomena are, but not that there *are* in fact no natural causes for for those phenomena.
Of course, in general it's practically impossible to ever actually *verify* any scientific theory; we just build our confidence in them because they make many successful predictions and we have been unable to falsify them thus far, despite our best efforts. But it's always possible something new observation could throw a wrench in the whole thing. So quantum theory isn't any worse off in that regard than any other theory. And of course there are logical proofs from the axioms of quantum theory that prove that certain predictions are impossible, but that's just to say that it's a theorem of quantum theory that certain predictions are impossible - which is sort of begging the question, since the question is whether quantum theory is right about that.
Which I guess is pretty similar to your conclusion - if you accept quantum theory as established (i.e. having held up well to testing), then you've got to accept its implications like randomness, including quantum randomness, just as a matter of course. But what people like the GP are saying is that quantum theory's particular prediction that we cannot predict certain things is in itself untestable, and another theory might come along later which successfully predicts the same things that quantum theory successfully predicts, but also predicts that we can make the predictions that quantum theory says we can't, i.e. describes a method for making such predictions. But unless something like that comes along and shows that we *can* make such predictions, it's an open question whether or not we can, because it's impossible to show that we *can't*, and it seems to me a rather defeatist attitude to just say "oh well, it's completely random", just as much to say "oh well, it's a miracle". Maybe it is - but it's more productive to keep searching for an explanation.
-Forrest Cameranesi, Geek of all Trades
"I am Sam. Sam I am. I do not like trolls, flames, or spam."
That's why we don't use the metric system in the US!
...that was partly responsible for this whole mini media frenzy, I just wanted to add a couple things. First off, the media coverage has been (I suppose not surprisingly) all about reporting Guenter Nimtz's sensational claims without hearing from the other side. The other side, in this case, is definitely the mainstream point of view... and Aephraim Steinberg at the Univ. of Toronto makes a very compelling counter-argument. The train analogy he uses is helpful.
But if you want to get more geeky, you don't even need to use any quantum mechanics or even relativity to explain what Nimtz is observing. You can also explain it using good old classical physics. What Steinberg is saying is that the microwave, which is a packet of some finite size, gets slightly delayed as it hits the edge of the prism. There's a component of the wavefront that continues propagating into the gap past the reflective surface. (Technically, this is called the wavefront's "evanescent mode" -- meaning it has a wavelength measured in imaginary numbers... so there's no physical wave in this region of space.) And if there's a small gap separating the two prisms, the wavefront returns to the physical world, with a real wavelength again, back inside the second prism. That's what quantum physics would call "photon tunneling." The seemingly faster-than-light transmission speed is just the consequence of the wavefront's being slowed down at the boundary between prism and air. So the sum-total of time the wavefront spent in transit seems faster-than-light when you only look at one portion of its overall trip. But other portions of its trip (i.e. at that boundary between prism and air) were being slowed down.
Of course to explain this in all its gory detail -- and I've kind of done a butcher job here -- requires a lot more words than we had room for in this piece. So the train analogy had to do.
The other thing, to get even more geeky -- and extra-credit is definitely awarded to anyone who picked this up in the story -- there is no such thing as 33 cm microwaves. (Wavelength too long.) That's a typo. It's 33 mm.
Consider this a big ol' nerdy D'OH!