Scientists Slow the Speed of Light

The speed of light is not a constant after all. Scientists have managed to slow the speed of light traveling through air for the first time.A team of scientists at the University of Glasgow have slowed the speed of a photon in space. They sent photons through a special mask that changed their shape. The altered photon was then raced against an unaltered one. Over a distance of one metre, the altered photon was slowed by up to 20 wavelengths.So far, the speed of light has been considered a constant and is used in physics as such. This experiment gives a new perspective for the properties of light. The research, conducted in collaboration with Heriot-Watt University, was published in the journal Science Express.Since light has both particle and wave nature, it is possible to change the shape of an individual photon as if it were a wave. The speed of light in free space is 186,282 miles per second. The speed of light is slower in water or when going through glass but returns to its original speed in air. In the experiment, however, the speed of light was observed to be slightly lower.The team of scientists compared the speed of light to a group of cyclists. While the group maintains a constant speed, each individual cyclist travels at his or her own speed. Similarly in a beam of light, each photon travels at its own speed even though the beam is traveling at a constant speed.The delay in the photon introduced during the experiment was measured at some micrometres over a propagation distance of one metre, but it is significant. The experiment is only applicable over short distances. This means that are fundamental understanding of how the universe operates remains unchanged, even though our understanding of light has evolved.To contact the writer, email: sonali.raj@gmail.com