Photons move faster than the speed of light

Scientists at the University of Koblenz (Koblenz, Germany) claim to have propelled photons faster than the speed of light-a feat that violates Einstein’s special theory of relativity.

Oct 1st, 2007

Scientists at the University of Koblenz (Koblenz, Germany) claim to have propelled photons faster than the speed of light-a feat that violates Einstein’s special theory of relativity. Using a phenomenon in quantum optics called photon tunneling, two glass prisms were sandwiched together to make a cube 40 cm on a side. Microwaves with a 3.3 cm wavelength shone straight through the cube, and when the prisms were separated, the first prism reflected the microwaves. However, in accordance with theory, a few microwave photons also tunneled across the gap separating the two prisms, continuing as if the prisms were still sandwiched together. The researchers found that the reflected microwaves and the few microwaves that tunneled through to the second prism both arrived at their respective photodetectors at the same time, suggesting an ultrafast transit between the two prisms-so much faster than the speed of light that it could not be measured. Because tunneling efficiency drops off with distance, the effect could not be observed across distances greater than 1 m.

Aephraim Steinberg, a quantum-optics expert at the University of Toronto (Ont., Canada), believes the experimental results. However, he adds, “Einstein can rest easy; it has been rigorously proved, many times and by many people, that no energy or information moves faster than light in these effects” (see physicsworld.com/cws/article/print/18660). Contact Günter Nimtz at G.Nimtz@uni-koeln.de.

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