Re: Absolute 0





Sam Wormley wrote:

Sitav wrote:
For my school newspaper I once did an article on absolute 0 and i know
that so far scientists have not reached that tempurature on earth. And
because of the Big Bang it is (theoretically) not possible in space. I
know that everyone that reads my articles thinks that I am just trying
to get answers for my homework, but if you think about it, i am 12.
What could a sixth grade teacher teach me in class about this? Anyway,
i have searched quite a few websites to try to find any place or thing
in space that could support that tempurature or whatever it is. (Isnt
it technically nothing?) But i couldnt find anything and i got grounded
for crashing the computer.


You should get a Mac...

some people's genes just wont permit it !

but that's off the point. Scientist has
achieved some pretty cold temperatures.

Ref: http://www.aip.org/pnu/1997/physnews.341.htm

Physics News Update
Number 341, October 15, 1997 by Phillip F. Schewe and Ben Stein

THE 1997 NOBEL PRIZE FOR PHYSICS has been won by Steven Chu of
Stanford, Claude Cohen-Tannoudji of the Ecole Normale Superieure in
France, and William Phillips of NIST for their development of laser
cooling for neutral atoms. In this case "cooling" means reducing the
relative velocities of atoms. In these experiments, an array of laser
beams converges on a gas of atoms. In the simplest type of laser
cooling, the wavelength of the light is tuned so that just the fastest
atoms moving in a particular direction will absorb a photon head-on,
thus slowing their motion in that direction. The atoms will eventually
re-emit a photon but in random directions. The effect of the laser
bombardment is a net slowing of the atoms. This "optical molasses" can
slow millions of atoms to temperatures just millionths of a degree
above absolute zero. Adding magnetic fields to the laser configuration
enables one to trap the atoms and cool them further. As a result of
these techniques, physicists can cool atoms closer to absolute zero
than ever before, to temperatures of nanokelvins in some cases.

.



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