Slashdot Mirror
The Law of Disassembly
An anonymous reader writes "Smalltimes has a story by Douglas Mulhall, author of Our Molecular Future, which discusses molecular nanotechnology (MNT) disassembly, and argues for what he calls the 'Law of Disassembly,' that 'every MNT product must be disassemblable by at least one [of several possible methods].' The article ends with some good suggestions for raising awareness of this important issue. Gratuitous quote: This is disturbingly reminiscent of "nuclear power will give us clean limitless energy, and don't worry, we'll deal with the byproducts later because we'll have the tools by then.""
From the article summary, I thought he meant "disassemble" as in reverse engineer and figure out how the things work, and I was thinking "cool, like open source nanotech."
But in reading the article, I found this is not what he's talking about. Instead he is talking about how to decommission various molecular nanotechnology (MNT) creations, and e.g. the difficulties that are created by shields and shells created around various small scale entities.
I think both of these sides to "disassembly" seem pretty damn important.
and argues for what he calls the 'Law of Disassembly,' that 'every MNT product must be disassemblable by at least one [of several possible methods].' The article ends with some good suggestions for raising awareness of this important issue. Gratuitous quote: This is disturbingly reminiscent of "nuclear power will give us clean limitless energy, and don't worry, we'll deal with the byproducts later because we'll have the tools by then.
This is idiotic. Any reasonable MNT device will be mostly carbon in a form very like diamond. Yes, diamond is cool; it's hard, light weight, etc. But it isn't some SciFi ubermatter. For instance, it burns pretty much the same way coal and graphite do.
As for the products of MNT, it depends a heck of a lot on what is beeing made. Is he seriously suggesting that we shouldn't be allowed to use MNT to produce clean drinking water for third world countries unless we have a way to disassemble it? Or he just techo-fearmongering without bothering to be serious?
I will agree though, it is disturbingly reminiscent of the FUD that was spread about nuclear power by the fossil fuel industry that has done so much for the environment (not to mention world peace).
-- MarkusQ
This monster called technology is a force we have to deal with. "Deal with" being the operative words: it is not something we control, at least not anymore. It is way too big, powerful, and important to be arbitrarily restricted, and any efforts to implement controls would have to be quick, effective, and global, i.e., practically impossible. In light of this, what the author of the article proposes is eminently reasonable and foresighted.
There has been much talk of the dangers of nanotech, for example from Bill Joy and others, and it is, or should be, a point well-taken. What the author proposes is twofold: when designing replicable nanotech devices, implement constraints on reproduction rates, and second and probably most important, design in disassembly through, for example, the ability to take the thing apart, or by biodegradabilty, or by oxidation susceptibility. In other words, prepare in advance an "achille's heel" that would allow a dangerous development to be easily disabled. I would only argue here that mutliple achille's heels should be designed in.
And, to quote from the article (yup, I read it, sorry):
No doubt there is much to argue with and discuss at this point, but that is the whole idea - let the discussion begin. The future is coming and the time to plan for it is now.=-+
"Which is more dangerous: a few kilograms of nuclear waste, packed up in (for example) ceramic blocks; or thousands of kilograms of coal smoke"
o n/ fission.htmls ion.asp
Thats a very stupid remark, lost your brain or what..?
I could easily create a dirty bomb with your few kilograms and nuke New York (hmm...)
I'll try to explain:
divide nuclear in- nuclear fusion and fission
nuclear fission will yield more energy than coal burning and creates a lot of waste, but less than coal,
Yes its more efficient but the waste will still be there when your grandchildren walk this earth
(don't let yourself be fooled its "only" a few kilograms, its a lie).
fusion on the other hand is more interesting(H-bomb)
Take a look at the sun, and you'll see a huge clean efficient way of getting about 90-99% of the chemical energy stored in molecules(actually plasma- the electrons/proton/neutrons have so much energy they wont attach to each other (for long))
But the problem is the sheer size of a plant which could contain the energies released
No worries we will be able to one day.
As you can deduce yourself, I am very much in favor of nuclear fusion, NOT fission
And all around people make more fission plants, very stupid indeed
http://library.thinkquest.org/17940/texts/fissi
http://www-pub.iaea.org/MTCD/NF/NFu
Not those particular isotopes. Nuclear reactions tend to create new less stable and hence more radioactive isotopes. The once that decay quickly are initially most dangerous, but it is the once with half-times in excess of a couple of thousand years that cause long term headache.
You're idea is nevertheless charming, but in order to get them into a region that really gets subducted completly you would have to dig a very deep hole. It'll be very expansive if at all doable. If you don't get deep enough you will just end up deposing nuclear waste in an earthquake prone area, and virtually gurantee that the ecosystem there will be contaminated sooner or later.
I'm frankly not sure where to start. Let's start at the end.
"Shouldn't cost any more than getting [uranium ore] in the first place."
And what do you suppose mining uranium costs? Yellowcake currently sells for about $10 a pound, and at that price the world's uranium producers are making a very decent profit.
I know many dozens of people in the industry from exploration crews to miners to management.
By "Reversing the mining process" I assume you mean burying it in the ground. Well, that's exactly what they're trying to do, but they do run up against a few probems. For example, if you don't use uranium ore for something, there's no point in mining it in the first place.
But, if you do use it, you inevitably turn it into something much, much more radioactive than the stuff we get out of the ground.
North Korea isn't trying to make bombs out of the stuff that goes IN to the reactor, they make it out of the stuff that comes OUT after they're done using it to boil water and run a steam generator to make electricity.
Different reactor designs vary so the quality of the waste varies as well. But, it's always more dangerous than the stuff that comes out of the ground.
There is more than one type of power-generating reactor that eat uranium, breathe electricity, and shits weapons-grade plutonium two years later. (Thankfully N Korea doesn't have one of those designs, so they have to jump through a few hoops first. But, they have a good start with the waste fuel from the type of power reactors they do have).
There is one sure-fire way to make radioactive material safe. It's called the passage of time. Ever handle a piece of lead? Well, a couple of billion years ago, it was uranium. All uranium eventually turns into lead.
So, if I understand you right, you're saying we wait a billion years until the waste we have is more-or-less the same as the stuff we took out (by then plutonium might decay enough to be similar to yellowcake), and then we bury it.
Gotcha.
The amount of radiation emitted by a mole of material is inversely proportional to its half-life. Thus, the stuff you put in the ground is a million times more radioactive than what was pulled out.
I wouldn't consider that vision conservative in the least.
Considering it is imposssible to create macrobots that can reproduce themselves, the prospect of microbots that can do it is practically inconceivable to me.
As a chemist who works in the area of nano-composites and nano-patterning the smallest self replicating robots I can imagine already exist...they are called single celled organisms. The chemistry involved in making nanobots is equally as complicated as that of organic life, no matter what element you make them out of. Speaking from a chemical perspective, the intellectual demands of creating a new type of what is essentially life from scratch (without using organic molecules) are way more than 50 years away.
My advice to computer scientists and engineers is to concentrate on macro sized robots that can reproduce themselves from base materials (such as sand). This is not as easy as it sounds! Such robots could easily build houses and other things such as solar panels etc., and are much more realistic in a 50 year timespan.
yay.
Read more...we didn't just yet,
but what would you care, its your grandgrandgrandchildrens problem now isn't it?
No, you haven't. Currently, we don't have any manageable systems available that produce more energy than required to keep the reaction going. (In fact, we don't have any manageable systems that can sustain themselves.)
I suppose the parent has a point in that a fusion bomb does produce enough energy to further itself, at least for a little while, and we simply don't have the technology to contain all the energy required to sustain a reaction of that type.
tasks(723) drafts(105) languages(484) examples(29106)
Take a look at the sun, and you'll see a huge clean efficient way of getting about 90-99% of the chemical energy stored in molecules
Chemical energy is what you get when e.g. you burn something: this is the energy from interatomic bonds (electromagnetic force).
Atomic energy is different, it comes from the bonds between protons / neutrons inside of the nucleus (I'd say it's the strong force but I'm not sure).
I think the mass loss for fission is 1/1000, 4/1000 for fusion (for chemical probably in the order of 10-e9) (of course E=mc^2)
I don't really know what your percentage means. The element with lowest nuclear energy is iron, so to get the most of nuclear energy ("100%") you'd have to turn everything to iron.
Amazingly precise surgery. Imagine tiny robots that could destro cancer cells, but leave healthy cells alone. Imagine if solid sheets of clear diamond were cheaper than glass.
Imagine if the only real cost to build a product (such as a rocket engine or a child's toy) were only the design (and then self-replicating nano-bots would take-over given a supply of common elements).
Yes, yes. This seems to be a long way off, but the scientific principles are sound even if we don't have the engineering know how yet. Furthermore, the risks are significant, so it's about time that we start planning for how to do these things safely and securely.
Read the book The Diamond Age Or a Young Lady's Illustrated Primer by Neal Stephenson. Besides being a fantastic (if strange) read, it gives an idea of the possibilities and (to some extent) the dangers of nanotech.
Also, check out Engines of Creation The Coming Era of Nanotechnology by Eric Drexler. It also explores the possibilities of nanotech, but presents a compelling case that we should be planning for this technology to make sure that it is safe secure and truly beneficial.
http://yetanotherpoliticalrant.blogspot.com