From: Robert J. Bradbury (bradbury@aeiveos.com)
Date: Mon Nov 25 2002 - 17:11:58 MST
On Mon, 25 Nov 2002, Lee Daniel Crocker, replying to me wrote:
> Surely (b) is unnecessary for huge advancement in manufacturing.
Unclear, Eric does not casually discard the systems complexity issues --
in fact IMO he points them out as being a quite significant problem.
Boeing did not get the 767 or 777 off the ground by simply "wishing" them
into being. (Each of them has several million "parts". Assemblers are
simpler but I'm not sure how much.) And many of us know what happened
with the first Arianne 5 launch -- and that was purely a software problem.
Complexity can sink your ship.
> If you can design macro-scale materials out of repeated segments of
> small numbers of atoms, and use even crudely-positioned disassembly
> tools to "carve" them into sub-micron-accurate shapes, and produce
> nano-"joinery" mechanisms in a similar way, that alone will be miles
> beyond anything we can do with traditional manufacturing but not
> require anything as complex as a car to be designed down to the
> molecular level.
True. But the devil may be in the details. I think there was a
a recent Nature article on super-strong copper that they mananaged
to get by cold-rolling it in LN2. They managed to get a combination
of large and small grain sizes in the metal that you could not get through
normal processing methods. (So they got a very strong but ductile material.)
The "carve away" and "nano-joinery" approaches will certainly have
interesting properties -- likely better than existing materials today.
(For example one can imagine a car assembled from nano-legos.)
But these objects will be a far cry from what you can get with
true nanoassembly.
Robert
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