Light travels at a constant speed of 186,282 miles per second. At least that is what you were taught in school, right? Well it seems that once again scientists have shattered the ideas of what was once thought to be “known”. Lene Vestergaard Hau, a physicist at Harvard University, has managed to slow down, and in fact stop a pulse of light, start it up again at 0.13 miles per hour, and then make it appear in a completely different location. This is truly modern day science fiction turned reality. So how does it work? The secret is to use a 0.1-mm lump of atoms called a Bose-Einstein condensate (BEC), cooled nearly to absolute zero (-459.67 degrees Fahrenheit) in a steel container with tiny windows. Next you take a laser with just the right wavelength and shine that into the BEC, which ends up tuning the optical properties of the atoms giving you a certain amount of control over any other lights that are shined into it. Finally… you guessed it, just shine another laser through it and revel in your newfound power!
Hau’s first accomplishment on the road to this feat was to slow a pulse of light to 15 mph as it traveled through the BEC. Now recently she actually managed to stop it mid-flight, and then using some quantum physics (another pretty mystical area), transfered the light to a completely different BEC and released it. If you’re interested in reading more about the experiment, see the original article from Wired Magazine, which also has links to several videos.