From: Max More (max@maxmore.com)
Date: Sat Jul 27 2002 - 13:50:24 MDT
AN ULTRA LOW-DENSITY LIQUID, some 10^13 times thinner
than water, might form inside Bose-Einstein condensates under the
action of the "Efimov effect," a quantum phenomenon in which the
atoms in the cloud attract each other when considered two at a time
but repel each other when considered three at a time. In such an
Efimov cloud the atoms would be some 20 times farther apart that
in a BEC, which is itself pretty sparse a million times thinner than
air. And yet this new type of condensate would not be a gas but a
liquid! According to Aurel Bulgac of the University of
Washington the exquisite coordination of atoms in an Efimov
condensation would allow it to be self bound (the constraining
magnetic fields used to keep a BEC from drifting apart would be
unnecessary); moreover, it would be neither compressible nor
dilutable. This extraordinary quantum liquid the smallest density
condensed matter system yet proposed---could probably only be
formed at much colder temperatures than are now available in BEC
experiments. Bulgac proposes that Efimov droplets made from
boson atoms be called "boselets." The fermion version would be
"fermilets." (Bulgac@phys.washington.edu, 206-685-2988,
Physical Review Letters, 29 July 2002)
_______________________________________________________
Max More, Ph.D.
max@maxmore.com or more@extropy.org
http://www.maxmore.com
Strategic Philosopher
President, Extropy Institute. http://www.extropy.org <more@extropy.org>
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