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Re: Detection vs Identification

From: Brian Quirt <baqrt@m...>
Date: Mon, 17 Apr 2000 12:12:49 -0300
Subject: Re: Detection vs Identification

Alan and Carmel Brain wrote:
> 
> From: "Brian Quirt" <baqrt@mta.ca>
> > First, what IS a "coolant laser?" I've never encountered that term,
and
> > I have NO idea what it could be.
> 
> http://www.optitemp.com/optitemp.htm
> Shows them in use as Water coolers (!)
> 
> http://www.colorado.edu/physics/2000/bec/lascool1.html
> has data about using lasers to produce subzero Kelvin (WHAT!)
temperatures
> but that's about individual atoms and bosons.
> 
> Basically, it's a way of inneficiently transferring energy away from a
> system by sending it out as photons. It's directional radiation, in
any amount
> required, by stimulated emission. Heat in->photons out. You can take
the
> temperature of any object down to whatever level you like, given
enough work
> to transfer the heat.

	Actually, from the information provided, it looks like the
lasers have
to be EXTERNAL to the closed system, which would make this slightly more
difficult to use. It also seems that, in accordance with thermodynamics,
the power you would have to put into cooling the atoms would itself
generate enough waste heat to counterbalance the cooling effect (note
that this doesn't keep the system from cooling atoms (or water), it just
seems that everything OUTSIDE the area being cooled would end up
hotter). I didn't see anything in either to suggest otherwise (and
neither water-cooling nor bose-einstein condensation require reducing
the heat level of the entire system, any more than refrigerators reduce
the overall temperature of your house).

-Brian Quirt


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