Scientists have observed a stunning demonstration of classic physics giving way to quantum behavior, manipulating a fluid of ultra-cold sodium atoms into a distinct tornado-like formation.
Particles behave differently on the quantum level, in part because at this point their interactions with each other hold more power over them than the energy from their movement.
Then, of course, there's the mind-boggling fact that quantum particles don't exactly have a certain fixed location like you or I, which influences how they interact.
By cooling particles down to as close to absolute zero as possible and eliminating other interference, physicists can observe what happens when these strange interactions take hold, as a team from MIT has just done.
"It's a breakthrough to be able to see these quantum effects directly," says MIT physicist Martin Zwierlein.
The team trapped and spun a cloud of around 1 million sodium atoms using lasers and electromagnets. In previous research physicists demonstrated this would spin the cloud into a long needle-like structure, a Bose-Einstein condensate, where the gas starts to behave like a single entity with shared properties.
"In a classical fluid, like cigarette smoke, it would just keep getting thinner," says Zwierlein. "But in the quantum world, a fluid reaches a limit to how thin it can get."
In the new study, MIT physicist Biswaroop Mukherjee and colleagues pushed beyond this stage, capturing a series of absorption images that reveal what happens after atoms' have switched from being predominantly governed by classical to quantum physics. READ MORE...
