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I'm figuring this belongs in quantum - sounds like a quantum effect.
http://www.opticsinfobase.org/abstract.cfm?id=63756
There's lots of papers like this ... also been in the blogosphere:
Sounds like some people are claiming to have done it for real:
These are representative samples from the less crazy end of the spectrum.
I could imagine the leading-edge of a wave-function faster than c so long as the group velocity was less. So I'm betting there is some crucial info left out which makes the result more sensational sounding than it should be.
What did I miss?
http://www.opticsinfobase.org/abstract.cfm?id=63756
(my emph)We study the propagation of light pulses through a transparent anomalous dispersion medium where the group velocity of the pulse exceeds c and can even become negative. Because the medium is transparent, we can apply the Kelvin's method of stationary phase to obtain the general properties of the pulse propagation process for interesting conditions when the group velocity: U < c, U = ± , and even becomes negative: U < 0. A numerical simulation illustrating pulse propagation at a negative group velocity is also presented. We show how rephasing can produce these unusual pulse propagation phenomena.
There's lots of papers like this ... also been in the blogosphere:
Sounds like some people are claiming to have done it for real:
http://scienceblog.com/light.htmlA team of researchers from the Ecole Polytechnique Fédérale de Lausanne (EPFL) has successfully demonstrated, for the first time, that it is possible to control the speed of light – both slowing it down and speeding it up – in an optical fiber, using off-the-shelf instrumentation in normal environmental conditions. Their results, to be published in the August 22 issue of Applied Physics Letters, could have implications that range from optical computing to the fiber-optic telecommunications industry.
These are representative samples from the less crazy end of the spectrum.
I could imagine the leading-edge of a wave-function faster than c so long as the group velocity was less. So I'm betting there is some crucial info left out which makes the result more sensational sounding than it should be.
What did I miss?
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