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Nanotechnology: Are Molecular Assemblers Possible?
Roland Piquepaille writes "Two experts in the field of nanotechnology, K. Eric Drexler, Ph.D., cofounder of the Foresight Institute in Palo Alto, Calif., and the person who coined the term "nanotechnology," and Richard E. Smalley, Ph.D., a professor at Rice University and winner of the 1996 Nobel Prize in Chemistry, exchanged open letters about "molecular assemblers" -- devices capable of positioning atoms and molecules for precisely defined reactions in almost any environment. These letters are making the -- long -- cover story of the current issue of Chemical & Engineering News. At the end of this rich exchange of four letters, they still disagree about the issue. Drexler thinks "molecular assemblers" are possible while Smalley denies it. Who is right? Don't count on me to give an answer. This summary contains some forceful quotes from the original letters."
Also interesting is Ray Kurzweil's comments on the exchange:
/ ar ticles/art0604.html
http://www.kurzweilai.net/meme/frame.html?main=
84-page peer-reviewed white paper on nanofactory. Conclusion: we see no hurdles, predicted time line: 10 years from now we could haave the first operating assembler... http://www.jetpress.org/volume13/Nanofactory.htm
Richard Feynman talked about nanotechnology way back in 1959
**bzzztt!* Wrong. Feynman was actually talking about nanobiology - the differences between the two are subtle, but distinct Yes, he did propose the possible usage of organic materical as "a relay for information" but that is where the similaties end. I can understand how they appear the same on a surface level, but please get your facts straight before spouting.
You're the one who doesn't know what he was talking about. He literally described using machine tools to make 1/2-size versions of themselves, then using those ones to make 1/2-size versions of them, and so on. He then argued about the scale down to which you could do that.
For a good book check out The Computational Beauty of Nature). Some tasks can be broken down into very simple repeated actions which simple machines can perform. The beauty of these system is that they require little communication between agents. Merely an awareness of what is around you and a simple list of tasks can create some complecated forms.
Take a look at this:
Here
From the article:
"an atomic manipulation facility, unique in the world. This atomic manipulation facility will enable a new generation of experiments to unfold. It will allow McGill researchers to construct new devices atom by atom, thus developing the science and technology required for future electronic and biochemical systems."
With regard to the hemoglobin molecule example this is precisely the problem that Smalley has -- a lack of knowledge. There are at least 3 other examples of a porphyrin ring carrying an atom other than iron known in nature. So it seems perfectly reasonable to structure alternative carriers. Yes, all possible tool tips will not work as expected. But the that does not mean that all possible tool tips will fail as well. The notion that mechanosynthesis will not work seems to contradict current chemical methods where chemical reactions occur by random interactions between atoms/molecules. If these aren't random mechanical interactions then I must misunderstand chemistry.
Granted. Feynman theorized that it could be done. He made a $1000 bet to his students that they could not construct a working motor 1/64 of an inch square -- He lost this months later when a student was able to produce it. Feynman was disappointed because he figured that the technology needed to get construction down to the molecular level would have sprung forth from his little grassroots project. This is where Drexler and Feynman differ.
The main difference between Feynman and Drexler, (and why Drexler deserves to have an equal share of the limelight) is Drexler is a more responsible scientist.
I highly recommend you stop on over to the Foresight Institute website [foresight.org] and see what Eric Drexler has been responsibly been working on for the past 20 years. There's an online version of Engines of Creation [foresight.org] available in which Drexler examines the hopes and dreams of Nanotech, minus the onesided utopia/distopian slant. Drexler has always been an advocate for technology to be developed by responsible hands (whoever that is) and asks Should We? as well as Could We?
I think this novel humanitarian approach to groundbreaking scientific development is a bit refreshing, don't you?
Chris McAllister=Cheers! Chris McAllister
Everyone seems to ignore the fact the with nanotechnology any disgruntled employee can manufacture a nanoplague that will kill off the whole world's population. Imagine something like a miniature time bomb that spreads like a cold virus. At a predetermined time it explodes (Diamond Age's cookie cutters), produces a poison, or compiles a toaster in your brain. With a GPS antenna (graphite is an pretty good conductor) this could be very location specific. With the capability to map the bloodstream, it could selectively kill fat people (body mass index), stupid people (small brains), blacks (thick lips), various asian races (epicanthic fold variances), ugly people (by scanning the face). And all this is no more difficult than compiling a toaster. You can't even enforce assembler containment; read about how Hackworth stole the primer (Diamond Age): any engineer working with assemblers could do exactly the same thing to get himself one. And this ONE MAN can kill off everyone in the world. Now tell me, which benefit of nanotech will offset this not-too-negligible danger?
You wrote: Then you should read more carefully. What I said was that Smalley's arguments were invalid (specifically, that he raised strawmen and argued from incredulity, both of which are known types of faulty reasoning). I then listed a number of reasonably well known cases from the last few decades where this sort of reasoning had led to, what are in hindsight, wrong conclusions.
I never claimed or implied that the existence of a flawed argument against a premise is a evidence for the premise.
You imply that I hold this view, while I clearly state that I do not. I agree that the sort of argument that you describe is invalid, but that is not the sort of argument I made.
-- MarkusQ
P.S. If you are interested in an argument for Drexler's position that I find compelling, I can outline one:
If you just read the exchange of letters, well, it does appear that Drexler does not properly address some of Smalley's points. Drexler points out that "fingers" are not needed, that there are other mechanisms for guiding the molecules to their reaction point. But he never elaborates on what these mechanisms are, nor addresses Smalley's issue about molecular reactions not being as simple as assembling Lego bricks.
I suppose if I finished reading my copy of Drexler's Nanosystems, I'd see more information about proposed methods of directing molecules and getting the desired reactions, but it's still not there in these letters.
Smalley is making one hell of a claim though, going from criticizing Drexler for not having clearly articulated (to his satisfaction) the methods of molecular assembly, to claiming that molecular assemblers are impossible. As Drexler points out with the quote from Smalley - when a scientist claims something is impossible, they are more than likely incorrect.
I understand Smalley's perspective, by trying to dissuade fears of runaway nanomachines and the like - but that doesn't mean Drexler's idea is wrong, but that the idiots that assume any nanomachine invented will instantly start replicating itself and turning the planet into grey goo. There's a higher likelihood of humanity being wiped out by a meteor impact, nuclear war, or the appearance of a super-virus than the grey goo occuring.
"You know your god is man-made when he hates all the same people you do."
There is no doubt that machines can be built that behave like cells. However, one should be careful not to claim without sufficient evidence that we can make cell-sized machines that do things that no cells can. Cells can't make exact copies of themselves and I don't believe a group of cells working together would have any more luck in completing that task.
Smalley isn't arguing that nano-scale machines are impossible. He's arguing that, without breakthroughs in chemistry beyond what we can currently imagine (ie some manner of "enzymes" not dependent on water or some other liquid), any molecular assembler that depends on the exact placement of individual atoms will suffer from tremendous error rates rendering the likelihood of creating a functional product infinitesimal.
I think Smalley went a bit far in declaring molecular assemblers impossible, but for now I don't think that we even know if the sorts of reaction paths needed exist or not.
My only political goal is to see to it that no political party achieves its goals.
The only similarity between the problems of AI and Single-atom positioning in nanotechnology is that they are both problems which we have seen nature solve, which gives us hope that we too will one day solve them.
Incidentally there is a lego mindstorms robot which can assemble copies of itself from parts lying on the table. If you can do that with a children's toy, then I have high hopes for purpose-built nanites doing the same thing.
Your example of a self-replicating factory is simply another straw man because the problem of nanites building nanites is so different from the problem of factories building factories. Given the use of robotics in factories, you would have to have a chip fab, refineries, and so on. However if you accept that some whole parts may be thrown into the system (like packaged ICs) then it actually becomes relatively simple to build a self-replicating factory, just pointless.
Nanites on the other hand are (will be) working with atoms. They don't need to do refining. The atoms they can manipulate are limited only by their manipulators, and if they have enough of each type of manipulator for each type of atom which is in their system, then they are physically capable of self-replication. Whether or not we will manage to make them do it is a question worth asking, but the most important question should be is it possible. Once we are sure things are possible we tend to wrap them up relatively rapidly thereafter.
Nothing has been said yet to prove that self-replicating nanomachines are impossible. They're certainly unfeasible with today's technology, but the nice thing about technology is that it progresses as time goes by with the efforts of talented and driven individuals, in spite of the naysayers. Meanwhile, you have offered no new arguments against the idea, and in fact made no useful comparisons.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
From the above linked article:
-Malakai
A Dragon Lives in my Garage
If you strip away the fancy words (and shamelessly simplify), this becomes much more obvious:
The argument is about putting molecules together mechanically, as Drexler proposes. Drexler repeatedly refuses to address this point. I agree with Smalley that mechanical positioning, as Drexler advocates, is an inherently very limited method.He's kind of pompus. Ask anyone who's taken his CHEM 102 Class at Rice. He's been like this even before the Nobel prize. He's smart, but at the same time he instantly lost the buckyball/nanotube crown after discovery because (so the rumor goes) his lab was unable to reproduce any of the results others were making in building new structures.
When I took that class, he made some statement about "spending Daddy's money to buy this book" which instantly pissed off some people. It was funny to watch them start protesting his class because of that one quote though.
(I've only read from the abbreviated version link, so I'm going to refrain from discussion until I go through the other one)
That's always good advice.
1. Diamonds aren't that rare.
2. DeBeers has created the artifical market for them we know of today - try selling those diamonds you just bought right back to the seller. He'll offer you a pittance if he'll even take them at all.
3. Diamonds can be manufactured. We still can't turn lead into gold as yet (or even Uranium for that matter).
Never invest in diamonds.
A while back, Sean Morgan did the most interesting work I've seen on a timeline and prerequisites for Nanotechnology. At present, odds are that we'll see an assember sometime around 2022.
Author: Atkinson, William Illsey
Title: Nanocosm: nanotechnology and the big changes coming from the inconceivably small
Summary: Atkinson is a technology reporter who surveyed the nanotech field (actually talked to researchers), and from his perspective, Drexler's assembler is not feasible, but he gives lots of other examples of nanotech now in labs around the world.
If you think Drexler is right, reading this book might change your mind.
It's a blurry line, but if I understand you correctly, you're saying you could (in the cell example) use nanotechnology to make the proteins themselves, but don't care where they float around in the cell itself, so long as they're in the general area. Like the mitochondria, the cell wall, etc etc.
Pretty much. The only exception is that if we needed to we could position the parts more exactly. Cells do this, by the way. They allow stuff to float at random only to the extent that exact positioning doesn't matter. Otherwise, molecules (or even medium large structures) are towed into position by active mechanisms, including ratchet-and-prawl devices that walk along micro-tubules.
-- MarkusQ
From the exchange, Drexler gives the impression that matter at the atomic scale behaves in the same way as matter on the macroscopic scale that we live in.
Physicists and chemists would know that this assumption is false. The Dalton theory of atoms as billiard balls has been refuted a long time ago.
How is a mechanical manipulator going to "grab" another atom? These manipulators are also at the atomic scale! Duh.
Today near the bottom of the http://www.foresight.org/ website, it shows a unrealistic graphic of one of Drexler's proposed nanofactories. There are what appears to be spherical atoms being manipulated by machinery. -- It fails to accurately show that the machinery is no more solid than the lego atoms that the machinery is manipulating. (Unless maybe the machinery material is made of some sort of selectively reactive/nonreactive, subatomic material)
When I see pictures & notions like that being bandied about and sold to the public, I get the same feeling when people push Jules Verne's voyage to the moon as science rather than science fiction. -- Baloney.
Right now Smalley wins. He's a doer, an implementer.
Drexler may get the last laugh in the far future, but some real science must appear first to make science fiction a reality.
The really hard stuff is in the implementation. The implementers deserver the real credit.
In other words fusion. Strong force bonds are 10^40 times stronger than electromagnetic bonds.
Femtotech (yes it already has a name)is significantly harder than nanotech.