C1ay Posted August 16, 2007 Report Share Posted August 16, 2007 A pair of German physicists claim to have broken the speed of light - an achievement that would undermine our entire understanding of space and time.... However, Dr Gunter Nimtz and Dr Alfons Stahlhofen, of the University of Koblenz, say they may have breached a key tenet of that theory. The pair say they have conducted an experiment in which microwave photons - energetic packets of light - travelled "instantaneously" between a pair of prisms that had been moved up to 3ft apart.... More at the Telegraph Quote Link to comment Share on other sites More sharing options...
freeztar Posted August 16, 2007 Report Share Posted August 16, 2007 Say what!?!?!?! :):eek::eek2::D The article is dissapontingly devoid of info. Hopefully tomorrow will have all the major news sources posting articles on this with more detail. This is potentially BIG, B-I-G news! :snow: Another good find Clay! Quote Link to comment Share on other sites More sharing options...
Jay-qu Posted August 16, 2007 Report Share Posted August 16, 2007 but i put a 99.99% chance on it been utter crap Quote Link to comment Share on other sites More sharing options...
Jay-qu Posted August 16, 2007 Report Share Posted August 16, 2007 I found this journal article by the same two guys - but dont know if it has anything to do with this because its in german :hihi: http://www.dpg-tagungen.de/archive/2006/frankfurt/q.pdf Quote Link to comment Share on other sites More sharing options...
freeztar Posted August 16, 2007 Report Share Posted August 16, 2007 but i put a 99.99% chance on it been utter crap You're probably right, but I hope you're wrong. Quote Link to comment Share on other sites More sharing options...
Jay-qu Posted August 17, 2007 Report Share Posted August 17, 2007 I had a chat with my physics prof today and he was of the same opinion that I had come to - its not a violation of relativity unless you can send information along with the tunneling photons. He said he had heard of experiments like this where photons locally appeared to have traveled faster than light, but in the end if you cant send info with them there is no violation of SR. Quote Link to comment Share on other sites More sharing options...
CraigD Posted August 17, 2007 Report Share Posted August 17, 2007 (edited) This post by turtle contains this link to a slightly better article on Nimtz and Stahlhofen claim. I’m pretty confident, when the hype clears, this will be revealed to be a simple – though understandable – publicity stunt, containing nothing scientifically unprecedented, not any technology capable of faster-than-light communication. Edited September 1, 2013 by CraigD Fixed broken post link Quote Link to comment Share on other sites More sharing options...
freeztar Posted August 17, 2007 Report Share Posted August 17, 2007 Yes, that article is much better and I would agree that this is yet another study that has jumped the gun. Their results have not even been reviewed yet. Quote Link to comment Share on other sites More sharing options...
palmtreepathos Posted August 19, 2007 Report Share Posted August 19, 2007 aw gee... broken you say? thats too bad......:D /forums/images/smilies/banana_sign.gif Seriously I read up on this tunneling of the electrons and that is very cool stuff... sort of a domino effect of the invisible kind? these are the random electrons from the air that are displaced from the previous motion? Or a flamelike projection of the electrons spinning off of the actual beam of light? Thx to turtle for that link and expanding this po' weak mind... :( Quote Link to comment Share on other sites More sharing options...
CraigD Posted August 19, 2007 Report Share Posted August 19, 2007 For anyone who’s not fully grocked Nimtz’s and Stahlhofen’s experiment, here’s a summary: The inside surface of one face of a triangular glass prism acts as a mirror, reflects effectively 100% of visible light. place 2 well-made (faces perfectly flat) prism together, however, and light passes through the inside face to emerge from the second prisms with no change in direction (see paths 1 and 2 in the attached image). N & S placed 2 prisms nearly, but not quite, together. According to ideal, classical (Newtonian) optics, light should be reflected as if the second prism were not present (path 3). However, in the real, quantum-physical world, a small (but rigorously calculable) fraction of the light passes straight through both prisms, as if they were not separated (path 4). This occurs because, in quantum physics, each particle of light (photon) is not a classical particle, with a definite position at any given time, but a distribution of probabilities of the particle being detected at a particular position at a given time. There is a definite, non-zero probability that a photon having entered prism 1 will, a moment later when classical optics predict it being reflected by the prism’s interior face, be located inside prism 2, allowing it to continue in a straight line as if the prisms were together. This “doing the classically impossible” is known as “quantum tunneling”. If you put a detector in the gap between the two prism, you would not detect a photon tunneling between them (path 5) – this effect is not a photon violating the laws of classical refraction and reflection, but realizing a less probable, but not impossible, quantum statistical outcome. The faster-than-light character of this experiment comes from the fact that this not-in-prism-1-but-instead-in-prism-2 tunneling effect is not movement in a classical sense, so doesn’t require any time to “leap” the distance. So, if as N & S appear to have done, you precisely measure the travel time of the tunneling photons, it will be briefer by at least the amount of time required for a non-tunneling photon to travel across the gap between the two prisms. So, the time required for light to travel from an emitter to a detector may be shorter – as N & S have demonstrated – for a photon passing through a couple of separate prisms (path 4) than through air, or possibly vacuum (path 6). I can find no fault with their reasoning or experiment, and am revising my previous opinion that this experiment is not much different than previous “faster than light light” demonstrations involving group velocities. From this, I think it's reasonable to conclude that one could construct from ordinary materials, such as glass, an long optical path, such as a fiber-optic communication cable, capable of transmitting a signal faster than a direct EM signal, such as a visible light or radio beam. I believe, as N & S and reporting journalists suggest, this really is FTL communication, and really does violate predictions of Relativity. When confronted with such a paradox, one should be mindful that, despite being a modern theory, Relativity is a classical mechanical, not a quantum physical, theory, so, in an absolute, objective-reality-based sense, is wrong when applied to experiments of this kind. Quote Link to comment Share on other sites More sharing options...
Jay-qu Posted August 19, 2007 Report Share Posted August 19, 2007 Your a real scientist craig, not holding any sentiments when it comes to some of the biggest and most accurately predicting theories we have! But one of the ideals of science is repeatability, and i am going to wait until this experiment is verified before I can believe FTL is possible in some cases! Quote Link to comment Share on other sites More sharing options...
Qfwfq Posted September 4, 2007 Report Share Posted September 4, 2007 I find this whole thing full of misconceptions and I would like to see an appropriate analysis, which I'm not expecting to do myself presently and would mean studying the evanescent wave with a variable incoming amplitude. Such a computation would be trickier than the steady-state one used for describing the Esaki effect and calculating just the emergent amplitude. I can't remember exactly textbooks say about it, from when I was on my course years back, but suspect Eisberg-Resnick warns against jumping to hasty conclusions of this kind. In any case, it is long known that the evanescent wave for constant amplitude has constant phase over distance, I doubt there having been no previous Clever Dicks thinking of the same idea. :confused: Quote Link to comment Share on other sites More sharing options...
LaurieAG Posted September 5, 2007 Report Share Posted September 5, 2007 This news is over 3 years old. The date is April 2004. Popular Science - Feature The microwave 'photons' have a 33mm wavelength and I bet they didn't use the exact same angular set-ups for all their tests at all the different distances. I even suspect that they had different angular set-ups for each microwave 'photon' equivalent, at each distance. Quote Link to comment Share on other sites More sharing options...
Erasmus00 Posted September 5, 2007 Report Share Posted September 5, 2007 When confronted with such a paradox, one should be mindful that, despite being a modern theory, Relativity is a classical mechanical, not a quantum physical, theory, so, in an absolute, objective-reality-based sense, is wrong when applied to experiments of this kind. While special relativity is classical, I think its also important to remember that you can make a relativistic quantum mechanics (quantum field theory) and it has been enormously successful. As such, I don't see how they can possibly be passing ftl signals. -Will Quote Link to comment Share on other sites More sharing options...
Buffy Posted September 5, 2007 Report Share Posted September 5, 2007 Not clear on how they're proving that its the same photon in both prisms: They could of course just be two separate but entangled photons, right? Even if this was the case, it would still be "faster than light transmission of information" which would violate SR too... Inanewyorkminute,Buffy Quote Link to comment Share on other sites More sharing options...
Qfwfq Posted September 5, 2007 Report Share Posted September 5, 2007 right?No, it's not the same thing as entanglement and I doubt were could use it to transmit info faster than c, which we can't do with entanglement either. Quote Link to comment Share on other sites More sharing options...
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