Re: A thread that has nothing to do with memes or the Singularity

Anders Sandberg (
Mon, 2 Dec 1996 16:12:39 +0100 (MET)

(great subject, BTW)

On Mon, 2 Dec 1996, Lyle Burkhead wrote:

> Suppose you want to build a cell that acts as a refrigerator. The cell
> contains a vacuole within which the temperature can be reduced to a
> point near absolute zero. How could this be done? What mechanism
> could the cell use to pump heat out of a small region? We assume that
> the cell has a source of energy, and that its surroundings can serve as
> a heat sink.

My guess is that it is very hard, mostly because heat is a macroscopic
phenomenon - if you just keep a single atom very still, have you created
efficient cooling? And on the nanoscale, everything is jumping around.

I think we need something like drexlerian nanotech for this, proteins
don't work well when temperatures change. In this problem, the hardest
part seem to be how to insulate the vacuole from the surroundings. My
suggestion would be a nano-dewar: two geodesic diamondoid spheres with
vacuum between them, kept concentric by electrostatic forces.

Pumping heat away from the inner sphere might be done using electron
bombardment; I seem to recall that this was used to cool down atoms. On
the outer sphere, nanostructures catch the electrons and send them in
again in a carefully designed beam (this is the part that costs energy;
entropy is pumped away using the electrons).

I think this is a rather fun problem, but I don't see much use for it.
What applications do you have in mind?

Anders Sandberg Towards Ascension!
GCS/M/S/O d++ -p+ c++++ !l u+ e++ m++ s+/+ n--- h+/* f+ g+ w++ t+ r+ !y