Physicists have found a way to overcome the speed of light barrier

American researchers have shown that wave interference can cause energy peaks to move faster than the speed of light — while information is still transmitted no faster than light, meaning special relativity is not violated. The work was published in the journal Physical Review E.

The effect was discovered while modeling sound propagation. In the calculations, a signal traveling at 1,500 m/s produced energy peaks that appeared to move at speeds of 1,694.5 and even 2,782.5 m/s. The reason is that direct and reflected waves overlap and shift the energy peak earlier than a single direct wave would have arrived.

"The speed of information transfer is less than or equal to the speed of light in a vacuum," emphasized the study's lead researcher, University of Pennsylvania acoustician John Spiesberger. Together with colleague Eugene Terray from the Woods Hole Oceanographic Institution, he reached this conclusion while studying how to track whale communications using hydrophones.

Testing with binary signals of zeros and ones confirmed that the information itself cannot outpace the direct wave, even though interference gives it a kind of "boost." According to the authors, the mechanism differs from quantum tunneling and anomalous dispersion, in which "superluminal" effects have also been observed.

The researchers suggest that a similar phenomenon may also manifest for light in a vacuum. The next step will be experimental verification of the effect using sound or light waves.