| Scientists
have created a new form of matter, which they call fermionic
gas, from a half-million potassium atoms chilled at close to
the coolest possible temperature. To do this, scientists used
lasers to trap the small cloud of potassium atoms. Once the
atoms were trapped, scientists chilled the atoms to 50 billionths
of a degree above absolute zero, or minus-459 degrees F.
Fermions are a class of elementary subatomic particles that
includes electrons, and they are among the building blocks
of atoms and molecules. According to a law of quantum mechanics,
no two identical fermions may occupy the same quantum state
because the matter behaves in waves and not individual particles.
But scientists found that when they applied a magnetic field
to the freezing atoms, the atoms would briefly match up in
pairs and create a condensate, behaving in a wave pattern.
Shortly, scientists will examine its behavior for evidence
into the paradoxical laws of quantum mechanics, but for now
there is no practical use for fermionic gas, they say. They
believe that eventually the gas could help engineers achieve
superconductivity, or the state in which electricity flows
without resistance, at everyday temperatures.
USA
Today January 29, 2004
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