Can Light Break Its Own Speed Limit?
Scientists have apparently broken the universe’s speed limit. For generations, physicists believed there is nothing faster than light moving through a vacuum-a speed of 186,000 miles per second. But in an experiment in Princeton, N.J., physicists sent a pulse of laser light through cesium vapor so quickly that it left the chamber before it had even finished entering. The pulse traveled 310 times the distance it would have covered if the chamber had contained a vacuum. Researchers say it is the most convincing demonstration yet that the speed of light-supposedly an ironclad rule of nature-can be pushed beyond known boundaries, at least under certain laboratory circumstances. “This effect cannot be used to send information back in time,” said Lijun Wang, a researcher with the private NEC Institute. “However, our experiment does show that the generally held misconception that `nothing can travel faster than the speed of light’ is wrong.” The results of the work by Wang, Alexander Kuzmich
