Molecular Manufacturing vs. Nanoscale

We've said it before, but it's worth reviewing: Why molecular manufacturing will be so much more powerful than nanoscale technologies.

Nanoscale technologies are not typically general-purpose. They may make a medicine, or a material, or a small structure with a specific purpose. But if you want to do a different thing, you have to invent a different technology, or combine several nanoscale technologies using some other process. Molecular manufacturing will be able to make complete products using a huge range of programmable shapes with a wide variety of mechanical properties and functions.

Nanoscale technologies are not typically as high performance as scaling laws would suggest. There are several reasons for this, including: fluid drag and floppy-molecule relaxation time in biopolymer technologies; difficulties integrating nanoscale devices into large high-performance systems; imprecise manufacturing techniques; and other limits on manufacturing, such as the planar nature of lithography.

Nanoscale technologies can't deliver huge amounts of information to the nanoscale, which limits the total flexibility and functionality of the manufacturing process. To handle huge amounts of information requires a processing system, and there are no nanoscale processing systems integrated with nanoscale manufacturing systems yet. Molecular manufacturing would be able to build such systems, which could incorporate gigabytes or terabytes of blueprint information into every product at no extra charge. The large machines used by nanoscale technologies (whether scanning probe microscopes or test tubes) also face scaling-law disadvantages that limit throughput.

When all these disadvantages are added together, it becomes clear that, however impressive the results achieved by nanoscale technologies, molecular manufacturing will be far more capable -- at least in its domain of engineered nanoscale machinery integrated into large intricate products.

Tags: nanotechnology nanotech nano science technology ethics weblog blog

Comments

[ADBatstone]

Nanotechnology REALLY disproved!!!

http://www.physorg.com/news66320589.html

"Scientists discover water is sticky on a small scale".

Looks like it's over for nanobots.

[Mike Treder, CRN]

A sticky situation for nanobots, perhaps, but not necessarily for nanofactories. They always have been planned to operate in vacuum with water vapor excluded.

[Chris Phoenix, CRN]

AD, here's a clickable version of that PhysOrg link. You can use standard HTML "a href".

Feynman back in 1959 said that oil would be an obstruction, not a lubricant, at the nanoscale. Protein nanobots use water plus squishiness as a lubricant, and they move just fine (hence, you're alive). Diamondoid nanobots won't need lubricant; google for superlubricity; and their inner workings will be sealed from water, so it won't be a problem.

Chris

[elypse]

I understand that there's a semantic problem that still exists regarding what "nanotechnology" means to the public at large, but I don't see how molecular nanotechnology is going to ever appear except out of research that is going on currently in "nanoscale" technology.

How do you currently envision guiding mechanosynthesis? What is holding back the creation of a nanofactory now? What research needs to be done that isn't being funded? I see incremental steps in SPM based lithography techniques, all of which will be necessary in order to determine, once and for all, whether MNT will be possible or just a pipe-dream. New materials are being designed (indeed one could say TRULY new materials: (see for example: Structural diversity in binary nanoparticle superlattices
ELENA V. SHEVCHENKO , DMITRI V. TALAPIN , NICHOLAS A. KOTOV, STEPHEN O'BRIEN & CHRISTOPHER B. MURRAY) that could end up being integral in developing MNT.

My current opinion is that MNT is not around right now because we don't know how to build a nanofactory - and I don't see how that's going to change without current research into nanoscale technology. All the somewhat implicit animosity against current research seems counterproductive.

[Chris Phoenix, CRN]

Elypse, MM does depend heavily on nanoscale technology research. I'm not sure where you heard the animosity. I'm certainly not saying that nanoscale tech is useless or unimportant. I'm saying that we need to look beyond it, and understand that nanoscale tech can't deliver everything that's been promised for "nanotechnology."

Chris

[elypse]

Chris,

I suppose I detect a general frustration with the direction of nanoscale research within the MNT community. My question is, more directly, what avenues of research do you believe are not being pursued that are, in fact, necessary for MNT to come to fruition? Given that any incremental steps toward asserting greater molecular/atomic control are likely to lead to academic accolades (and commercial wealth if the process can be done in parallel/rapidly) I don't see what the forces are that are holding things back. Of course, you can always throw more money at the problem (and as a researcher in this area, I'd be happy to have more money) but failing that - what aren't we looking into?

[Chris Phoenix, CRN]

There are several avenues that are not being pursued with the energy that I'd expect if MM/MNT were understood. For example:

Theoretical studies: Nanotech seems to be driven almost completely by lab work. That's fine for short-term products. But it won't be very effective at finding the way that will get MM developed efficiently.

Mechanosynthesis: a lot more reactions could and should be simulated. AFAIK, Freitas and the Zyvex team are doing the only work on diamond deposition.

Large system integration: MM implies the ability to build huge aggregations of nanosystems. AFAIK, I'm the world expert on nanofactories; why won't someone please take that title away from me?

Similarly: design software. MM will need a part description language capable of specifying molar quantities of operations, produced by software tools that combine advanced CAD with multilevel and multimodal specification, simulation, and debugging. It's probably a good thing we don't have that, because the lack of it will slow down MM's impact. But if nanotechnologists were working toward MM (rather than just working on things some of which happen to lead toward MM) then they'd be working on that software.

Why is it that the calculations in Nanosystems are still up for debate? They should all have been either criticized or provisionally accepted by now (14 years after publication).

A meta-point: Why is it that so much really bad scientific practice was allowed to persist for so long? I'm referring to the ranks of nanotechnologists who asserted that MM couldn't work for some trivial reason that had been analyzed and dealt with a decade before. If you wonder why there's frustration in the MM community, look no farther than that. "It can't work because of quantum uncertainty"--Five minutes of calculation will show that that's BS. But scientists said that, and similarly bogus claims, in public statements for years. They never showed their work, and none of the arbiters (science writers, reviewers, etc) asked them to. And so for years, work targeted toward MM was stalled. In fact, working on MM was a career-limiting move; I heard from several sources that anything Drexler-related wouldn't get funded and could cause career problems.

If Nanosystems were understood, and at least provisionally accepted, then it wouldn't be necessary for me to write blog articles like the one you're responding to. It would be obvious that, when it comes to manufacturing high-performance nanodevices, nanoscale tech (including "nanomanufacturing") is just a milestone, not an end goal. And MM researchers would see it as a (scientific) milestone, rather than a (political) distraction.

You say that incremental steps are likely to lead to academic accolades and perhaps commercial wealth. Here, I'll go back to theory-vs-lab. For some reason, MM-related theory stopped being publishable around the late 90's. (Perhaps this was correlated with Smalley's and SciAm's opposition?)

For years, it's been the case that MM theory led what could be done in the lab by a pretty substantial margin. If that theory had been pursued, it could have inspired specialized tools and targed research paths. That didn't happen. Instead, even people who were interested in MM (both theory and practice) eventually had to leave the field, though some are now able to move back.

The people who want to see MM happen early have a whole lot of reason to be frustrated. Me? I'm frustrated that MM hasn't been talked about. At least a decade has been wasted, during which we could have been preparing for MM's implications, but were not even able to talk publicly about "that science fiction stuff." (Until recently, the NNI's website declared that nanobots were dangerous, science-fictional creatures.)

Now, we may have less than a decade left. And MM is still widely eclipsed by nanoscale technologies, which while interesting and useful, don't have even the same class of dangerous implications. So it's still hard to talk about what MM will bring.

I hope this answers your question. If not, please ask again. It's worth looking at how we got where we are today, because we can't afford to repeat that history.

Chris

[elypse]

Chris,

I think this is a useful conversation. I certainly can't take the blame for the entire scientific community, since I am just a graduate student nearing completion of a PhD - and don't have the potent inertia of someone like Rick Smalley (RIP) or Whitesides that can lead to such widespread aggravation. That being said, both Smalley and Whitesides had their own large-scale visions of nanotechnology that they were trumpeting and I suppose they didn't want MM to compete with.

That said, I think that is is very rare in any branch of science to be able to get much theory funded that cannot be tied to experiment. That may in fact be the problem, but I think it has much less to do with SciAm's opposition or Smalley's opposition than it does the dearth of experimental data to help push the theory stuff forward.

I think the reason that there's so much more being done on Si substrates than with diamondoid is quite simply because of the huge amount of money in the semiconductor industry. That's why companies like Zyvex are important in theory - if they start making money at something, suddenly there will be the economic incentive pushing other companies and then academic research. I think until there's some breakthrough papers showing some of the preliminary steps to MM are possible, you aren't going to see the theory and simulation work funded that you would like to see funded.

I work at one of the pre-eminent nanotech centers in the world, and I can tell you for a fact that I've seen Nanosystems on the shelves of several of the professors here - and I don't think it is with any derision. They're aware of the work (as a grad. student I'm aware of the work too) - but we need some hard data. Once that happens, you'll see the other studies you want.

I'm not trying to be annoying at all and I hope I'm not aggravating you, I'm just trying to give you my somewhat-informed (but still newish) perspective on what I see going on within the scientific community.

[elypse]

Let me add, that I agree whole-heartedly with you that it is very foolish not to discuss the potential societal and ethical implications of MM in an open setting. I was mostly talking about the pace and direction of the scientific community as a whole.

[NanoEnthusiast]

Chris, your main complaint seems to be the lack of more simulation work, I agree that this a problem. But, ideally in science you want a feedback loop between theory and lab work. You could argue that modern tools are insufficient to test what is currently being simulated. Take Freitas' latest paper, how could you build and then mount that tooltip to test if the simulation matches reality? I think the conservative nature of scientists demands that theory not get too far ahead of observation, so it seem that stagnation is inevitable. However, it does seem as though MNT has been singled out. Look at string theory, no one complains how far out on a limb that goes. Also, you could argue that simulations of nano-machines are even more likely to be correct than macro-machines, because every atom is being simulated. This is of course dependent on the model being used, preferably density function theory. More money on simulations would be nice, but at least this part of the equations falls in price will Moore's law, so even if you are limited to a shoestring budget the job will get done eventually.

On the subject of tools, I wonder if most scientist are happy with current SPM tech. I wonder if some of the improvements in tools you would like to see would be of any use to people during more conventional research.

With regards to software, I am not sure it is even possible to write a compiler for a nanofactory without a detailed design spec, if I am wrong please tell me why.

At this point in time I don't think there would be much difference in where money would be spent in lab work if Drexler himself was in charge of the NNI. He is, after all a proponent of the protein path to MNT. The challenge is, as I see it, is to get people to take these ideas seriously soon; because in the future there will be a fork in the road when it comes to funding. It is good idea to prepare now.

On the point of societal and ethical implications, I too think it is vital that this be discussed.

One final note, I wish that the Smalleys and the Whitesides would be honest about their long term visions, about how they too are founded on a many unproven assertions.

[Phillip Huggan]

I'm reading a paper about an attempt in the 1990s to contruct an SPM system where the tip can be positioned at 1 nanmeter increments. This is at least an order of magnitude too coarse for diamond mechanosynthesis, yet the paper describes difficulties in achieving even this. The construction blueprint details 4 or 5 different shells to screen out different forms of noise.

I'd say our SPMs are still pretty crappy right now. With every computer simulation essay, perhaps a benchmark of the closest thing to the simulation achieved in any lab should be mentioned too so as not to confuse the public.

[Chris Phoenix, CRN]

Elypse, I appreciate your participation, and I don't think you're annoying or aggravating--you're asking good questions.

I agree that it's hard to do science driven only by theory. But that doesn't excuse scientists for saying that MM is impossible!

NanoEnthusiast, you're right about tools being important, but which tools to develop depends on which pathway you're working on. Better X-ray sources for crystallography studies? Better SPMs for direct mechanosynthesis? Here's where we could really have used some basic theory--to learn more about which bootstrapping pathways will likely be easiest.

We couldn't write software end-to-end without a detailed nanofactory spec, but we could start learning how to write it. Even writing software for a completely imaginary nanofactory would provide useful experience. And then designers could start learning the workflow. Another point is that most nanofactory products will be designed several levels above the atoms, and that level of design/abstraction can be developed in advance of the specific designs, knowing only the general physical parameters.

Philip, I'm pretty sure I've read about mechanosynthesis operations being done *at room temperature* nowadays. Even AFMs are imaging with atomic precision, and STMs have been there for quite a while. So SPMs are difficult, but I think they have the basic precision needed already. Note that Freitas has proposed an experimental program to do carbon dimer deposition with SPMs--with today's technology.

Chris

[elypse]

Freitas proposing experimental programs to do carbon dimer deposition is a good step forward - I'll take a look at that proposal, but the next step, obviously, is for someone with the necessary UHV-STM system to go ahead and give it a shot.

In response to some of the above posts on the status of SPM tools, let me make a few technical clarifications. First off, AFM images are able to be used in ambient, but I am extremely skeptical of anyone who says they can get atomic resolution using AFM in ambient conditions - in fact, I'm nearly 100% sure this has not happened. The reason for this has to do with the water meniscus that coats your AFM tip and also your sample. Most AFM images with 'atomic' resolution are taken in STM mode and are under vacuum. However! The great advantage of AFMs, as you point out Chris, is that they are able to make some pretty spectacular measurements in liquid phase and in ambient conditions and they have gotten a lot better over the past few years. The big driver here has been the usefulness of AFMs for biological applications (which, down the line leads, I suppose to the protein path to MM).

STMs on the other hand continue to improve in resolution and have also been automated to a certain extent. You may wish to peruse the website and publications of Joseph Stroscio over at NIST (http://physics.nist.gov/Divisions/Div841/Gp3/Projects/STM/aaa_proj.html)
- he has some pretty nifty automated STM programs that do rapid 'assembly' (not how you are thinking, but still cool) of atoms. I'd say these are IMPORTANT steps toward achieving MM and go back to what I was saying in my original post, which is that I feel the scientific community is moving forward in a way that should interest the MM community and current nanoscale technology is evolving into something else - which even if it isn't full-blown MM - is still not just a repackaging of old technology under the subverted banner of nanotechnology.

My advice continues to be along the lines of what Freitas and Merkle have been suggesting and then one step forward. Make the experimental measurement - it goes a long way toward convincing people!

[Phillip Huggan]

One reason I prefer STMs over AFMs is that with STMs it is possible to ensure the probe has a single molecule tip via the quality of sample imaging. This allows tips to be presorted and those that aren't sharpies can be processed for recharging.

[Chris Phoenix]

I didn't mean to imply that AFMs were imaging with atomic precision at room temperature. Mechanosynthesis at room temperature, and AFMs with atomic precision--two different reports. (But room temperature doesn't imply ambient; you could perhaps avoid the meniscus by working in a dry-nitrogen glove box.)

The programmed atom manipulation is cool. But the
Aono group was doing covalent pick-and-place of silicon atoms on crystal Si surfaces... back in 1994. I know, this NIST group is doing really cool research into electronics that Aono probably wasn't even trying. It's not that the NIST work is useless. But I question whether it's necessary for MM, and I wonder whether we could have done the automated placement a decade ago if we'd been more interested in mechanical atom placement.

Yes, the scientific community is moving forward. Yes, their work is relevant, and much of it is not overly hyped. But I don't think the denialist position is erased even yet, and it will probably be a while before most people who are working in directions leading toward MM are willing to recognize and acknowledge that fact.

And it will probably be a while before nano-scientists become willing to acknowledge that there's a huge gap in performance and purpose between MM and nanoscale technologies. Until that recognition happens, I'll keep drumming on that point--not to criticize nanoscale, but just to emphasize that MM is coming and it will be DIFFERENT.

Chris

[elypse]

I don't think they think that nanoscale technology is as powerful as MM is trumpeted to be; I think most nanoscientists think MM doesn't apply to them because they either see too many technical challenges to achieving it at this stage (i.e. that's 50 years off - won't effect me) or have bought into one of the various counterarguments to MM.

So once the experiments happen that start to convince people otherwise (either from within the nanoscale community or from Zyvex or whomever) then I think you'll get what you want.

Addendum to AFM in ambient discussion: Even at very low humidities such as those provided by a simple nitrogen glovebox (which I have used for AFM), it is very difficult if not impossible to get rid of a water meniscus. I can get you references if you want - even in UHV conditions removing water is the most challenging aspect of the process.

I suppose if you wanted the scientific communities most common gripe with "theroetical engineering" of the type described in nanosystems and elsewhere in the MM community is that it typically overlooks so many other technical challenges - which is why a lot of these experiments don't end up happening. I assure you most of the mechanosynthetic experiments you describe would be very high impact and I'm sure there are people who have gotten nowhere trying to do them. But maybe that's just the frustrated "I've been banging my head against the STM and AFM for the last 200 straight hours and haven't gotten anywhere" graduate student talking (perhaps it isn't operated by headbanging?).

[NanoEnthusiast]

The problem is as I see it, if SPM based MM is like the computer revolution or like space colonization. Computers built is the 50's were clunky compared to modern ones, but there was a lot of demand for computers even just a little bit better than those of the 50's. This created a feedback loop where more money could be spent on R&D for better machines. If there was no demand for incremental improvements to get us to the modern Internet, I doubt we would have the Internet now, or forever for that matter. The demand for space travel is like that, we have no demand between where we are now to full-fledged colonization and mining.

I wonder if there is going to be the demand nesacarry to create a revolution in SPM tech. Current tools seem to be adequate for most researchers, take the Rice nanocar for an example. They took an AFM to look at the thing, then they picked it up on the tip and pushed it on a gold surface to see if the wheels rotated like they expected. For their purposes current AFMs were more than adequate. If it is only the MM community that (to the best of my knowledge) pushing for better SPM technology, I am worried that it will not be enough to provide incentive to the relevant companies. I hope that current lab work grows to the point that there will be a demand for the kind of improvements that we need to bootstrap MM.

[elypse]

Nanoenthusiast,

Look to the biotech industry. There's a strong demand for better AFMs and probes for biological applications and that is reflected in a rapid push forward in recent years.

And I don't know a single researcher out there who wouldn't welcome better tools (especially if you are providing the grant money to buy them!)

[Chris Phoenix, CRN]

Elypse, not to take us in circles, but...

The fact that nanoscale technologists bought into the arguments against MM is a major and legitimate source of frustration. Although many of the people who used the arguments simply hadn't done their homework, there were those who should have known better, who were in a position to be influential--and knew it--and who took public positions supporting bogus arguments. Both individual notable scientists and mainstream science publications (Scientific American spent column inches remarking that "Drexler pours milk into his ice tea" and "speaks with an exaggerated professorial tone that is faintly reminiscent of the pedantic 1960s cartoon character Mr. Peabody.").

As for lack of experiments, there were experiments that could have been done sooner if they hadn't been opposed; there were experiments that were in fact done, but were not mentioned as supporting MM; there were experiments that supported MM, and were mentioned by others as supporting MM, and those who mentioned them were attacked by the people doing the experiments, who didn't want to be associated with MM (which seems strange if MM was just another scientific theory).

You know, you should skim my debate with Bill Atkinson from a few years ago. It will give you a picture of the type of opposition MM has faced for many years. While researching a book on nanotech, Atkinson talked to lots of nanoscale technologists, and was led to believe that Drexler was a flake and a charlatan, and that MM couldn't possibly work for obvious reasons.

After we cleared that up, he advised me that the way to advance MM was to: 1) dump Drexler; 2) quit citing unaffiliated researchers' experiments as support for MM, because it annoyed them. I don't think this is how science should be done.

I'm glad you aren't seeing this kind of opposition today. Perhaps it means that enough of the opposition has dissipated that we can start moving forward. But the frustration has a very real source and a rather recent history. And it will probably take a while longer before the last pockets of anti-scientific opposition die off, and even longer than that before their impeding ideas fade away. (Note I'm not talking about legitimate uncertainty--I'm talking about unfounded negative opinion.)

There was not, after all, a lot of frustration in my original blog post. But when I start thinking about the very real harm done by the targeted and deliberate opposition to molecular manufacturing that persisted for more than a decade...

I believe that unnecessary delay of MM may turn out to have been responsible for the death of millions of people: from lack of advanced nanomedicine, from ecological and political problems due to unsustainable pre-MM technology, and from negative outcomes that could have been avoided if we had been able to talk about MM earlier. On a more personal note, it bothers me when people claim to be in a high-standards position like science, and then act according to lower standards. If you detect frustration leaking through my posts, it does have a source.

Chris

[Edited by Chris after posting.]

[elypse]

Chris,

I'll take a look at the Atkinson debate - I read another of your exchanges with a research scientist in the UK a few years back and I am generally familiar with the types of opposition MM has faced from some scientific luminaries.

If I were K. Eric Drexler, I can certainly understand feeling very angry and bitter about how all the hard work has been received and unfairly derided by people in the scientific community. My only point was that a few scientific big-wigs don't speak for everyone in science (as I know you are aware) and my guess is that most people are kind of like me - they are skeptical and will be until they see more evidence.

For what its worth most scientists I know are also very skeptical of things like string theory and will remain skeptical until there's some way to test it. They'll set aside that skepticism a little once it begins to pass tests. The main reason, I think, is that most people probably aren't capable of raising a serious objection to Nanosystems - but at the same time there aren't many people who seem to be able to come up with a good way forward on the subject either (except to continue 'nanoscale' research).

Like you, I get very angry when I think about how money is spent in this country. I'll be honest with you - I'm not sure whether MM is possible, but I certainly don't discount it and I wish we'd get more funding to look into it. As perhaps you are aware, it is very difficult to get things funded these days if it doesn't have to do with military programs or direct commercial tie-ins, and thinking about how we spend our money in this country makes me very upset as well. Even without MM, I think we could be saving millions of lives with more responsible spending filled with more foresight. And, if the predictions of you and Drexler (and Freitas, and Merkle, and Kurzweil, etc. etc.) are correct we really have been squandering our time.

Best wishes.

[NanoEnthusiast]

The thing that really irks me about the funding, is that historically the government has funded things that will not have a payoff for many years or decades, now with the NNI they seem to only fund things with rather near term application. I think the private sector left to its own devices, would have funded most of the things the NNI is currently funding. This creates a problem because now companies will assume the government will being paying for all their near term R&D. Why would you pay for anything out of your own pocket, if the governmet will? This leaves little money left for long term projects. (like a detailed MM feasibility analysis)

[Chris Phoenix, CRN]

Elypse, sounds like we agree--skepticism good, ignorant opposition bad. And you're right, there are probably lots of ways we could save millions of lives (at least in the short term--the long term is a bit trickier).

NanoEnthusiast, an effect you implied, and I think is worth making explicit, is that if the government switches from paying for basic research to paying for near-term commercial stuff, then *no one* will be paying for long-term basic research (except a few foresighted companies here and there).

It gets worse when the government actively opposes long-term research. Which they have done in a few key areas where the US could have been great. Almost enough to make me bring thin aluminum sheets to my next millinery class.

Chris