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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.
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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The headline leaves only one question (Score:5, Funny)
Re: (Score:3, Funny)
Re:The headline leaves only one question (Score:5, Funny)
Parent
Re:The headline leaves only one question (Score:5, Funny)
Parent
Re:The headline leaves only one question (Score:5, Funny)
Nice, even my cat liked that one. How do I know? Simple observation.
Parent
Re:The headline leaves only one question (Score:5, Funny)
"Is it dead?" asks Schrödinger.
"I can't be certain", says Heisenberg.
Parent
Re:The summary leaves only one question (Score:4, Interesting)
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
Parent
186,000 miles per second (Score:4, Funny)
and the penalty for breaking this law? (Score:5, Funny)
Parent
Re:and the penalty for breaking this law? (Score:5, Funny)
Layne
Parent
The missing C (Score:5, Funny)
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.
Parent
Re:The missing C (Score:5, Funny)
Good move, I guess that's checkmate.
-
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Just won't do... (Score:5, Funny)
Re:Just won't do... (Score:5, Funny)
Parent
How quaint (Score:3, Funny)
Another explanation from Ars (Score:5, Informative)
Re:Another explanation from Ars (Score:5, Interesting)
Parent
quantum spin (Score:3, Interesting)
Re: (Score:3, Informative)
Cheers!
Re:quantum spin (Score:4, Informative)
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].
Parent
Great..... (Score:5, Funny)
*Grabs salt shaker* (Score:5, Funny)
Every couple of years (Score:5, Interesting)
Re:Every couple of years (Score:5, Informative)
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.
Parent
Re:Every couple of years (Score:5, Funny)
I use Ms. Jolie because she is frequently mentioned as part of an "entangled pair".
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Re:Every couple of years (Score:4, Informative)
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.
Parent
Re: (Score:3, Interesting)
Incredible? (Score:5, Informative)
Not discrediting the achievement. This will help us clarify current theories regarding speed limits and stuffz
Cheers!
Informative (Score:3, Funny)
Next article from Germany (Score:3, Funny)
Way to go Anywhere Really Phast
Or WARP
Nothing new.. (Score:4, Interesting)
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.
Ob. South Park reference (Score:3, Funny)
"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.
measuring nanoseconds (Score:3, Interesting)
I thunk.. (Score:3, Informative)
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.
Re: (Score:3, Informative)
As for Cherenkov radiation, the speed of light is only constant inside a vacuum.
Matter People, Matter!!! (Score:4, Informative)
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)
Talk about old news... (Score:4, Interesting)
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.
Re:Actually (Score:5, Informative)
"God does not play dice" is about the inherent randomness in quantum physics.
Parent
Re: (Score:3, Informative)
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:
Re:Actually (Score:5, Insightful)
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.)
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Re: (Score:3, Interesting)
Randomness established? What experiment could possibly establish randomness? I'm with Einstein on that one.
Re:Actually (Score:5, Funny)
"Einstein, stop telling God what to do."
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Re:Actually (Score:5, Informative)
Then there's Hawking: "Not only does God play dice with the universe, He sometimes throws them where you can't see them."
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Idiocy (Score:4, Insightful)
The summary does however call photons "energetic packets of light" when I think they're trying to say "packets of energy".
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Re: (Score:3, Funny)
Cheers!
Re:Wrong about microwave photons (Score:5, Funny)
Only if you're within 52 light years of him.
Parent
Photons do not have mass (Score:5, Informative)
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.
Parent
Re:First Post! (Score:5, Funny)
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. ;)
Parent
It's sorta like this (Score:5, Informative)
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
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