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In the News:
Scientists Create New Form of Matter
We experience the three basic forms
of matter—solid, liquid, and gas—
every dayas we go about our lives. But
scientists have described other forms of
matter that are unusual, to say the least.
In January 2004 scientists produced a new
form of matter. They call the new form “fermionic condensates.”
Most of us know the properties of
ordinary solids, liquids, and gases. We
learned those in elementary school. Solids
resist changing shape and have a constant
volume. Liquids flow, they’re hard to
compress, and their shape can change to
fit any container. Gases are compressible;
they can change shape and volume.
Before the creation of fermionic
condensates, two other forms of matter
were identified: plasma and Bose-Einstein
condensate, or BEC. Plasma is gaslike
and composed of atoms that have been
ripped apart into ions and electrons.
The Sun is made of plasma. Plasmas are
usually very hot and need to be stored
in magnetic bottles.
Bose-Einstein condensates (BECs)
were discovered in 1995. They exist when
scientists chill particles called bosons to
very low temperatures. The cold bosons
join together to form a superparticle
that is more like a wave than an ordinary
speck of matter. BECs are very fragile.
Light travels through them very slowly.
Fermionic condensates are also cold
(hence the name “condensate”). Deborah
Jin, a physicist at the National Institute
of Standards and Technology (NIST) at
the University of Colorado, created the
new form by cooling a cloud of 500,000
potassium-40 atoms to less than a
millionth of a degree above absolute zero.
Fermionic condensates probably flow
without viscosity, but that’s about all that
scientists know about their properties.
Fermionic condensates are so new that
scientists have not discovered all of
their properties.
BECs and fermionic condensates are
probably related, although they are made
of different particles. Scientists describe
the bosons in BECs as sociable. That is,
they like to get together. Fermions, the
particles in fermionic condensates, are
antisocial. But Jin and her group found a
way around their antisocial behavior. They
came up with a “Cupid”—a magnetic field that caused loner fermions to pair
up and then pair up with other pairs.
Why is the new form of matter
important? It’s related to superconductivity.
The new form of matter might allow
the production of superconductors to
produce cheaper, cleaner electricity and
the construction of levitating trains and
ultra-fast computers. It may even play a
role in the establishment of a permanent
base on the Moon.
With fermionic condensates, six forms
of matter have now been identified.
But that number is still being debated by
physicists. Some suggest that liquid
crystals, glass, ferromagnets, and other
forms might still be added to the list.
They’re not sure that BECs and fermionic
condensates belong on the list with solids,
liquids, and gases. The debate continues.
To find out more about fermionic
condensates and BECs, check out the
following references.
http://science.nasa.gov/headlines/y2004/12feb
_fermi.htm http://jilawww.colorado.edu/%7Ejin/introducti
on.html
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