Dry Nano, Wet Nano

Chris Phoenix, CRN's Director of Research, writes:

I've recently been talking with a scientist who asserts that I alienate scientists by focusing on diamond-based "dry" nanotech to the exclusion of biochemical-based "wet" nanotech.

This indicates a misunderstanding that needs to be cleared up. We do not think that dry nanotech is the only kind that matters. However, it is the most powerful kind that has been specified to date. As such, until someone either shows why it can't work, or proposes a more powerful technology, this is the one we use as a benchmark.

There's another reason to focus specifically on Drexler's work as described in Nanosystems. Physically, it either works or it doesn't. As far as CRN can tell, it should work. But some prominent people, for a variety of reasons (most of them unscientific, and all of them inconclusive), are telling us that it can't. We think there's a good chance that someone who ignored those denialists would be able to follow Drexler's lead and create a very powerful technology.

If we are talking about what molecular manufacturing might be capable of in 20 years, and the implications of that capability, then we must consider the possibility of diamondoid nanosystems, or something of equivalent power.

When I say "Performance many times biology might be possible with diamondoid," everyone hears a different thing, and each person has a different reason for opposing the idea. Some want to defend funding, some want to rule out gray goo, some think their research project is better, some are upset by such an "unnatural" proposal, and some object that the details are probably wrong. So the discussion cannot progress sensibly because unrelated kinds of opposition reinforce each other improperly.

Let me state our purpose and reasoning in defending the Nanosystems work.

The purpose:

To prevent the world being taken by surprise by someone who has put Nanosystems into practice but will likely use the resulting capabilities irresponsibly.

The reasoning:

1) Nanosystems appears to describe a plausible and very powerful technology.
2) Someone who took Nanosystems seriously would invest in exploring and developing that technology, probably in secret.
3) Even if Nanosystems has a flaw (though none has been found yet), someone who investigated it with an engineering mindset would probably be able to devise an equivalently powerful technology.
4) Many people (especially in America) have never studied Nanosystems, or don't even know it exists, and have no clue that it is plausible.
5) If a group from step 2 succeeds, they will have access to a disruptively powerful technology. This will be a big and probably unpleasant surprise to the rest of the world.
6) The ability to do nanoscale engineering is very rapidly getting easier. If something comparable to Nanosystems is achievable at all, it could happen quite soon. We can't be prepared unless we start taking the possibility seriously.

Comments

[jim moore]

An idea for a lab experiment.

In order to show critics that it is possible to mechanically break and form chemical bonds, I suggest the following:

Etch two long thin beams (maybe a micron thick and a millimeter long) out a single diamond crystal.
Put the diamond beam in an ultra-high vacuum chamber.
Mechanically break the beams.
Press the cleaved end of beam one into the cleaved end of beam two.
If the ends of the diamond beams form covalent bonds between their cleaved ends you have shown experimentally that it is possible make diamond bonds through mechanical means.

( I guess Smalley could say that the beams loved each other thats why the chemical reaction happened ;-)

[Richard Jones]

I wonder if I am Chris's scientist. If so, I should clarify some aspects of my position. Firstly, I don't agree with Smalley's objections to MNT; Jim's experiment isn't necessary because the possibility of mechanically forming and breaking chemical bonds is amply confirmed theoretically and experimentally. There is an issue about the degree of control you can apply, but I believe there is experimental work going on doing chemistry with functionalised STM tips which already goes beyond what Smalley thinks is theoretically ruled out. Ironically, it is the degree to which uncontrolled mechanochemistry causes trouble to MNT by causing friction and wear that is one of the main points of my discussion with Chris.

Secondly, as for my motives. Nothing to do with funding; my own work is supported quite well enough, and given the amounts going in to nanotechnology at the moment there is enough funding to support many competing approaches (which is exactly what ought to happen, to my mind). As for gray goo, I think this is an issue that should be addressed head-on as a substantial and interesting scientific argument, and I think the attempts by Smalley and others to simply close down debate are unwise and actually counterproductive. No, my motives are (a) I think I'm right (though I know that it's entirely possible that I'm not), (b) I think it would be healthier if the scientific community seriously engaged with Nanosystems rather than simply ignoring it, and (c) because vigorous debate with informed opponents sharpens one's own thinking very effectively.

As for CRN's mission, I actually think that most of the outcomes they worry about will come to pass with or without MNT, so I think their work is potentially very valuable either way.

[Chris Phoenix, CRN]

Yes, Richard, you're the scientist I was writing about who said I was alienating bio-researchers.

But I was not writing about you when I talked about funding, or alluded to people who say MNT can't work for a variety of unscientific reasons. You have said, if I understand you, that it probably can work to some extent but that in your opinion other ways are better.

Our discussion has always been on a scientific level. We disagree on technical points--and we also agree on many. And I think you don't grasp the power of the MNT proposals--you criticize the details piecemeal without asking, "What would it mean if something along these lines actually worked?" But if Smalley and Whitesides would think as you do, the nano discussion would be much improved.

And, in case it's not clear, one thing we definitely agree on is that a wide variety of approaches should be investigated.

Chris