Has Robert Boyd, the M. Parker Givens Professor of Optics at the University of Rochester, succeeded in pushing light into reverse? To avoid breaking Einstein's rule that nothing can travel faster than light, the explanation for the phenomenon distinguishes between the information light carries v. its actual speed:
The leading edge carries with it all the information about the pulseand enters the fiber first. By the time the peak enters the fiber, the leading edge is already well ahead, exiting. From the information in that leading edge, the fiber essentially 'reconstructs' the pulse at the far end, sending one version out the fiber, and another backward toward the beginning of the fiber.
It certainly fits the physics-is-information kick I've been on. I like what Kevin Kelly says to introduce his Edge.org piece, "Speculations on the Future of Science":
The achievement of science is to know new things; the evolution of science is to know them in new ways. What evolves is less the body of what we know and more the nature of our knowing (emphasis supplied).
Science just may make epistemologists of us all. Or, in other words, what's known is new again.