New studies show that light is not the same speed at all times. What we have been calling the speed of light might just be the maximum speed of light!
Here's a quick excerpt from Stephen Ornes, reporting on Feb 3, 2015 about the new findings originally published by D. Giovannini in Science on Jan 22, 2015.
Light-speed pulses can slow down, even in a vacuum
Light travels as particles and as waves. Photons are the name given to those particles that represent the smallest possible amount of light. At their fastest, photons travel nearly 300 million meters (almost 1 billion feet) in a single second. That's fast enough to get to the moon and back in about 2.6 seconds. Scientists had long known, though, that they could slow light photons down by shining them through a material such as glass or water.
Still, light moving through a vacuum has usually been assumed to move at peak speed. That would seem to make sense. After all, a vacuum is a space with nothing in it to slow light down. In a new study, however, scientists show that even racing through a vacuum, light can slow.
