NialScorva

From the research I've seen, I think nanotech is going to be a narrow square bladed chisel in our toolbox. It'll let us carve out new details that we have been unable to up till this point, but there are other tools that will be as useful or more. There's even other tools that work on the same level of detail, just for different tasks.

It's just being sold as if the narrow blade chisel is a replacement for all carving tools, and possibly screw-drivers as well. There are going to be some cool apps for it, I think that what it's hyped to do is the least likely things we'll see it used for (manufacturing).

Corwin

Actually it's more along the lines of a complete toolkit. Exceptionally useful for some things, but generally useful as well. A big part of the problem with 'not being able to do the things we want to do' isn't that we can't build what's required, but rather that we can't afford to do it, or the materials (from natrual sources) are too scarce.

Could we make buildings with diamond reinforcement? Sure. It's possible. Currently it isn't feasible because synthetic diamond is too expensive to produce. However, if we gain the tools to go in and assemble carbon atoms, (from graphite or, let's say... trash...) into the characteristic lattice structure of diamond, suddenly a whole new world opens up.

It's one of these incredibly basic ideas that once you have it, things that 'weren't worth the effort' before become simple enough to do them on a routine basis.

NialScorva

Again, you have the thermodynamic problem of manipulating any perceivable amount of matter.

Corwin

...which can be overcome (among other ways) by throwing large amounts of an abundant fuel source at the problem. (Such as ATP.)

There are those who consider brute force to be unacceptably inelegant.... these people have never been faced with a stuck jar lid.

Nat

Corwin,

What about the heat released by the rapid eaking and forming of chemical bonds? At the speeds being considered (and necessary for most applications) the heat build up would be too quick to safely disapate and would like roast the host!

Nat

Corwin,

I just want to make it clear that I am not against nanotechnology and I firmly believe that it will be extremely useful (I mean, enzymes are basically nanobots and life has been using them for a good 3.5 billion years). I am, however, very skeptical of some of the more fanciful claims.

Corwin

Either allow the nanites to draw energy from heat, (thus increasing overall efficiency as well as dealing with heat damage to the subject) or build a structure that can take that heat energy and store it, to be released later. (Like a vessel full of liquid.) Two solutions, and not the only possible ones either.

alek0

Corwin,
Self-assembly is entirely different thing from self-replicating nanomachines. Self-assembly is entirely possible, and that is the method how nanostructures are fabricated today. Demonstrated InGaAs quantum dot lasers were made using Stranski-Krastanow growth mode, i.e. self-assembly. In our lab, we also use self-assembly. In self-assembly, however, you are restricted to configurations which offer minimum energy (or minimum strain) and you have a distribution of sizes of the fabricated nanostructures.

Concerning your proposed solution for "sticky fingers" problem, how do you think that nanomachine can replicate then? Even if it wouldn't have sticky fingers problem for some elements, it would certainly have that problem for making identical copy of itself.

Edited to add: how much energy do you think you can store in a couple of nanometers? As for using the heat, easy to say, but are you aware of any practical solution how it could actually work? You should also take into account that no energy conversion process is 100% efficient.

[ September 20, 2002: Message edited by: alek0 ]</p>

Christopher Lord

If nanotech is impossible as a self-replicator, why then does BIOLOGICAL nanotech work fine?

Protiens are simple nano machines which copy, move, turncate, modify, etc. other protiens and other atoms. These protiens make up cells, which are themselves MEMS of astronomical complexity and functionality.

Before one discounts nanotech, they have to explain why biological nanotech works fine, and what the difference is.

Energy is not a problem, since it can be delivered in chemical, photonic, or kinetic mediums.

Heat removal is a true problem of nanotech, and biology manages this by having a limited metabolisim.

alek0

Biological system does not manipulate individual atoms. There are certainly less objections to manipulating individual molecules than manipulating individual atoms. Furthermore, biological systems typically perform very limited functions, so that they are in no way analogous to universal assembler as presented by Drexler.