From: keithl@klic.rain.com (Keith Lofstrom)
Newsgroups: sci.nanotech
Subject: Re: Surviving
Date: 25 Jan 93 22:07:03 GMT
Article-I.D.: planchet.Jan.25.17.07.03.1993.10196


In article <Jan.19.22.41.18.1993.23082@planchet.rutgers.edu> cuhes@csv.warwick.ac.uk (Malcolm McMahon) writes:
>
>I  don't find the hot-house idea very credible.  What  conditions  would 
>nano  be  likely  to  require?   Not  high  tempartures  and  pressures, 
>certainly,  in fact thermal motion is an important problem.  More likely 
>vacuum  and cold.  Vacuum is easy enough to do at home.  Let's  look  at 
>cold.  Suppose,  to  take the extreme case you had nano that could  only 
>operate continuously in surroundings at a few degrees  absolute,  liquid 
>helium temperatures.  The operating temperature would have to be a  good 
>deal higher (to create the thermal gradient and dissipate the heat).  So 
>nano  that  would operate continously with  liquid  helium  temperatures 
>would  almost certainly operate briefly at liquid nitrogen  temperatures 
>that are readily available.

I think the "hot house" idea here means "special environment".  Eric Drexler
uses the analogy of a car - your average Chevy isn't going to head out into
the woods and start foraging.  Nor can any factory device you can point at.
We made the transition from trained animals like horses - which can forage -
to automobiles which cannot fend for themselves.  If the infrastructure
is there, an automobile is much more logistically manageable than a horse,
even if the horse is more logistically complete.

The same is true for virtually everything we design.   Since we can
separate reproduction and material processing from construction, we do.
The result is more rubust and predictable systems.

So what does this mean for a system of assemblers?  Well, even if it is
possible to build a complete and self contained machine, that would be
a lot more difficult than building systems of heterogeneous machines,
each specialized as to the function ( communication, fuel processing,
manufacturing, defense ) it performs.  At the macroscopic scale, you
put up a machine that combines cad system, machine shop, and fighter
bomber against my simple unifunction interceptor, and my simple machine
will wipe out your complicated (and thus suboptimal)  machine.

Now the chances that one of these specialized machines will go rogue
and prevail is about the same chance that one guy with a nuclear bomber
could take over the world.  It would take a large constellation of
machines going rogue, and you can partition the systems so that this
becomes logistically unfeasable.  Any technological community, even
a microscopic one, involves a vast wealth of design information that
cannot be duplicated easily - simply witholding the information will
slow down rogue system attempts to become self-sufficient and dangerous.

Thus, a hothouse system can be formed that is dependent on external
energy, materials, or information.  If the system misbehaves it is
simply deprived of necessary inputs until it succumbs.

Keith
-- 
Keith Lofstrom         keithl@klic.rain.com       Voice (503)-520-1993
KLIC --- Keith Lofstrom Integrated Circuits --- "Your Ideas in Silicon"
Design Contracting in Bipolar and CMOS - Analog, Digital, and Power ICs