Molecular Assemblers

[ygolo]

This is an old topic, but one that occupies my mind often.

C&EN: COVER STORY - NANOTECHNOLOGY

In this C&EN exclusive "Point-Counterpoint," two of nanotechnology's biggest advocates square off on a fundamental question that will dramatically affect the future development of this field. Are "molecular assemblers"--devices capable of positioning atoms and molecules for precisely defined reactions in almost any environment--physically possible?

[Athenian200]

Honestly, it doesn't seem like Smalley understands the idea at all, and is mostly concerned quelling his student's fears and using traditional metaphors and symbols rather than clear understanding. He keeps (in my opinion, irrationally) insisting that Drexler is talking about manipulating things with robotic arms (which he never stated), rather than enzymes, simply because of what he knows about enzymes as they exist in our current understanding of chemistry. He doesn't seem to get that Drexler is attempting to convey the idea that we may develop the ability to create and manipulate something that works like an enzyme, but is not exactly like the ones we have today in terms of how it would work. Drexler believes that we can figure out how enzymes themselves work, and eventually construct something that works on a similar principle, which seems possible and worth trying towards given our current level of knowledge.

On their character...

Smalley has a good understanding of the present situation and current knowledge, but he seems to lack vision and a spirit of honest curiosity and inquiry. He doesn't strike me as a man of science, but rather as a concerned father who doesn't want his children's minds to be troubled due to an intangible threat that, based on current knowledge, may never materialize.

Drexler seems to have good vision, an ambitiously inquiring spirit that seeks to solve problems, and is very punctilious in his descriptions, never wasting words, citing his works where possible instead of rewriting what he has already written. However, he leaves enough gaps in his stated argument due to his efficient and theoretical/mental operation that he fails to assuage Smalley, who fills in all the gaps with his own ideas and present knowledge/assumptions, which say it could never work. He expects Smalley to be able to have more vision than he actually does, and thus doesn't elaborate on his meaning or dismiss Smalley's arguments, assuming that Smalley can follow the ideas he points to without needing to be walked through them.

So, what do you think? I know next to nothing of chemistry or physics, and this was my impression.

[ygolo]

I've been away from regular internet access for the last few days, so that's why I didn't answer (went down for graduation. yay!)

I think both are well respected scientists.

I think you are right about Smalley seeming to lack vision. However, I think he is doing it on purose, in an attempt to force Drexler to think about some practical issues that he seems to be neglecting.

Drexler on the other has a long view vision, but there is a question of how realistic that vision really is.

It has been a long time since Feynman "There is plenty of Room at the Bottom" article, and no molecular assemblers have been man-made (let alone ones that can replicate themselves).

A great deal of Drexlers own work is "in prepreation/anticipation" of identifying a mechanism to crate molecular assemblers instead of the creation of said assemblers.

Its the classic debate between creating something in practice, and knowing that something is "theoretically" possible.

I certainly hope Drexler is right and we can have molecular assemblers and nano-manufacturing. But that hope has no bearing on the result (at least at the moment).