German physicists claim to have broken lightspeed barrier

Well they didn’t last time… not all of it anyway, but who knows, they could strike it lucky next time :smiley:

I’ve read the paper, available here. They haven’t shown a violation of Special Relativity.

An important thing to understand is that Maxwell’s equations do not violate Special Relativity. In fact it’s only a little bit overstating the case that Maxwell’s equations are the basis of Special Relativity. See Einstein’s On the Electrodynamics of Moving Bodies where he introduced Special Relativity, or “Does the inertia of a body depend upon its energy content?”, published three months later, which contains the statement “The principle of the constancy of the velocity of light is of course contained in Maxwell’s equations.”

The paper’s authors claim of a violation of Special Relativity seems to hinge on the argument that “the zero phase shift of spreading evanescent modes implies that barriers [between the prisms] are crossed in zero time.” It’s not valid to claim that zero phase shift for an evanescent mode implies zero time. Further, they seem to be assuming that propagation of energy from one prism to the other occurs in a direction normal to the surfaces (see their figure 1), but evanescent modes that are present in total internal reflection propagate energy parallel to the surfaces. Any energy propagation from the coupling between the prisms would best be described as flowing at an angle, down and to the right in their figure (although describing the energy as flowing along a line is really not a valid description for this experiment). As Procyon’s link states, there are no measured data, and insufficient experimental detail, so it’s impossible to say what this angle would be. In short, nothing they present is qualitatively anything other than what would be expected from solving Maxwell’s equations (and quantitative data is sorely lacking). Maxwell’s equations do not violate Special Relativity, and neither do their results.

By the way, they also claim that the evanescent fields are virtual photons, and are a non-classical effect (they reference is themselves). But again, evanescent fields are exactly what are predicted classically using Maxwell’s equations, with no quantum mechanics needed.