Scottish scientists have managed to make light travel slower than the speed of lightby changing the shape of photons, causing them to slow down. The groundbreaking experiment could open up new avenues in the science of light..
Researchers from the universities of Glasgow and Elliott Watt, led by physicist Miles Paget, who published the relevant paper in the journal Science Express, according to the BBC and "New Scientist", created (with the help of an infrared laser) a "race" of photons in pairs, during which one photon traveled in its normal state and the other changed shape as it passed through a special mask.
Comparing the speeds showed that the second photon had only slightly slowed down (by a few millionths of a meter, or a deceleration of about 0.001%). Remarkably, the light continued to move more slowly even when it was back in empty space, having passed through the mask (a liquid crystal device controlled by special software).
It is known that light always moves slower when it passes through materials such as water or glass (the phenomenon of refraction that creates optical distortions in the observer's eyes), but in empty space it should always have the same absolute speed, which is considered constant (the well-known "c").
As all physics books state, the speed of light in a vacuum is 299,792,458 meters (a little less than 300 kilometers) per second. In the case of the experiment, however, the photons traveled at a slower speed even in empty space.
In any case, the researchers said, their experiment does not challenge Einstein's theories of relativity. It is also questionable whether there will be any practical applications from the new discovery. The British scientists believe, however, that what happens with the "distorted" photons should also apply to sound waves, which are also expected to lose speed if they pass through a similar mask.
Source: APE-MPA
