Tuesday, February 9, 2010
A Sonic Black Hole
A black hole is a pocket of density so intense that light cannot escape. Scientists have created a sonic black hole - that is a pocket of space from which sound cannot escape.
Cooling rubidium atoms to just barely above absolute zero, a laser shot into the cloud created a void. The atoms, attracted to the breach, left the pocket at +4 times the speed of sound, creating a black hole type effect. No sound wave could travel against the flow of the racing fluid - much like trying to swim against a current much faster than you.
Aside from being real cool, a sonic black hole could help evaluate Stephen Hawking’s prediction that a real black hole slowly evaporates as it emits radiation.