Physicists who study black holes— collapsed objects whose gravity is so potent not even light can escape— can't get anywhere close to their deadly quarry. So they are salivating at the news that two physicists, Ulf Leonhardt of the University of St. Andrews in Scotland and Paul Piwnicki of the Royal Institute of Technology in Stockholm, have uncovered a way to mimic a black hole with a small, safe vortex of cold atoms.
The key to lab-grown black holes, no bigger than raindrops, is to spin the atoms faster than the speed of light. Then, like swimmers caught in a violent whirlpool, passing beams of light get sucked into the current. Normally it would be impossible to move the atoms quickly enough. Last year, however, physicists at Harvard University found that light slows tremendously when it travels through a unique, low-temperature state of matter, called a Bose-Einstein condensate. The Harvard team braked light's speed to just 38 miles per hour.
Leonhardt and Piwnicki think a batch of frigid rubidium atoms could push the process further, until light crawls along at about an inch per second. "Then the vortex would have to spin at several feet per second, which is certainly possible. Optical black holes could be just a couple of years away," Leonhardt says. These atomic swirls will let the researchers test ideas about how black holes swallow matter and bend space, as predicted by Einstein's theory of relativity.
