I'm sorry, but theoretical (particle) physics just gets me hot...
July 23 — A form of matter called Bose-Einstein condensate, which first was created in a laboratory in 1995, has been tinkered with until it caused miniature explosions that resemble exploding stars called supernovae, according to a new study.
A GROUP of physicists who created the Bose-Einstein condensate by cooling atoms of the rubidium-87 isotope to near absolute zero say they have developed a new “flavor” of the matter that has delivered a series of surprises.
The group, led by Carl Wieman of the University of Colorado at Boulder and Eric Cornell of the National Institute of Standards and Technology, says the material, a collection of atoms, behaves like a single “superatom.”
The latest work involved tuning the interactions between the atoms to make them attractive or repulsive by exposing them to magnetic fields, Wieman said. The group cooled the matter to just 3 billionths of a degree above absolute zero, the lowest temperature ever achieved.
BOSENOVA BLAST
By then fiddling with the magnetic fields, the researchers shrunk the condensate and forced a tiny explosion, which they say resembles a supernova, albeit in a microscopic level.
The team has dubbed the explosion a bosenova.
“We have gotten down to the nitty-gritty science and have been able to study the behavior of a new material by manipulating it in new and different ways,” Wieman said. But he added that several effects of the explosion were inexplicable.
The condensate first shrunk into small clumps as expected, but rather than gradually clumping together in a mass, a sudden explosion sent hundreds of atoms rushing outward. The explosion led to an outward moving shell or jets of material, much like an exploding star.
CHILLY REMNANT
The explosion corresponds to a tiny amount of energy and continues for a few thousandths of a second, the researchers report. A small chilly remnant of the condensate is left behind, surrounded by the expanding gas. About half the original atoms mysteriously vanished.
“The theoretical calculations of what would happen in this situation predict behaviors that are totally unlike what we’ve observed,” Wieman says, “so the basic process responsible for the bosenova must be something new and different from what has been proposed.”
The Bose-Einstein condensate is named after Albert Einstein and Indian physicist Satyendra Bose, who predicted its existence in 1924. A paper on the new work appears in the July 19 issue of the journal Nature, and Wieman first discussed it in March at a meeting of the American Physical Society.
http://www.msnbc.com/news/603958.asp