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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?
http://arstechnica.com/news.ars/post/20070816-fast er-than-the-speed-of-light-no-i-dont-think-so.html
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.
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.
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.
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.
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. ;)
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.)
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.
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