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Drexler Clarifies Grey Goo Scenario
b00le writes "The BBC says that the scientist many regard as the father of nanotechnology has backed away from his famous claim that runaway nanomachines could turn the planet into 'grey goo'. Eric Drexler now says nanomachines that self-replicate exponentially are unlikely ever to enter widespread use. So that's all right, then, but he also said 'tiny machines would need close control' - which not everyone would agree with. I always imagined some kind of emergent behaviour would, er, emerge." Bill Joy is still suitably pessimistic.
building requires consumption of raw materials which is what the grey goo scenario was refering to... the self replicating machines need raw materials to replicate, and the point was that the machines would exponentially reproduce, (doubling at the rate it takes to build a new nanobot) they need material to produce that, they take that material out of whatever is nearby... turning the earth into grey goo...
In a world as hyperparanoid as the current one is about weapons of mass destruction you have to wonder about technology that might enable a new class of WMD's when it falls in to malevolent hands, for example terrorists or the U.S. military.
You can't really blame the military. They are just obeying the politicians. If you want to blame someone, blame the 60% of the electorate who can't be bothered to vote.
LK
"Hi. This is my friend, Jack Shit, and you don't know him." - Lord Kano
They already have -- we call it the biosphere. The real problem with a grey goo scenario is that the nanobots would have to compete on a level playing field with organic life, which has had billions of years to get better at it then them. I expect nanotech will have to be used in a sterile, highly ordered, and energy-rich environment in order to get anything done.
The scalloped tatters of the King in Yellow must cover
Yhtill forever. (R. W. Chambers, the King in Yellow
"You can't really blame the military. They are just obeying the politicians."
Sometimes. But politicians come and go. The military is a big, self perpetuating bureaucracy and it has ways to get what it wants over time. The military frequently applies significant pressure on politicians to sucker them in to doing misguided things. For example they inflate the power and danger of supposed enemies and they will insist the other guy is doing it so we have to which almost always works. The movie, "Dr. Stangelove or How I Came to Love the Bomb" is about the best parody of this ever, especially when the world is doomed and the generals start claiming there is going to be a "mine shaft" gap after the world is destroyed.
If you look at the history of the Cuban missile crisis you'll see Kennedy barely restrained the military from provoking World War III, they weren't happy with Kennedy's decision making, and he mysteriously gets killed soon after.
If you look to the 50's, MacArthur also nearly pushed the U.S. in to a nuclear conflict with China that would have also probably lead to World War III. Truman once again barely contained him against his powerful set of Republican friends and his huge popular support.
The once place you are right is Iraq where the civilians in the white house and pentagon, Cheney and Wolfowitz, fabricated an entire case for a war and apparently got away with it.
@de_machina
Maybe you should have ended that post with a IANAS (scientist) disclaimer. In both high school and college debate, nano was my primary and favorite topic for years, and I frequently debated on both sides of the issue. The one argument that I could never win against nano was an attack on Drexler's qualifications.
Perhaps he should not be called the father of nano. The real father of nano is Richard Fayman. In his lecture entitled "There Is Plenty of Room At the Bottom" he basically invented the concept. Drexler, however brought it forward. He has a Ph.D. in Molecular Nanotechnology from MIT (a degree that did not exist before Drexler was awarded it). His S.M. and S.B. are both from MIT as well. He was a research affiliate for two departments at MIT and a visiting scholar at Stanford, where he taught a doctorate level class. As recently as 1993 he won the Kilby Yound Innovator Award. He has testified before Congress, written dozens of articles and books, even winning the 1992 Oustanding Computer Science Book for Nanosystems, a VERY technical book almost impossible to understand for anyone without at least a M.S. in Chem or Engineering (or both!). He holds numerous patents, and has lectured everywhere from Apple and Bell Labs to TI and the Xerox PARC.
Disbelieve if you want, but please do not be so foolish as to challange the credentials of Dr. Drexler.
I'll address each problem in your argument one at a time:
,000 in there...not really a problem, but still an error.
I think 14 trillion might be overstating it by a few orders of magnitude... I'll assume you just put in an extra set of
There are hundreds of billions of different things on this planet in abundance which as far as we know the universe has never created by random chance. Imagine the incredibly complex set of random events which would be required to build the CPU of the computer you are sitting at right now.
So just because the universe has never created it by random chance it can NEVER happen, huh? What the hell does "of the order of E=mc^2" even mean? That's like saying "of the order of X^2=Y". I'm not sure if you realize this or not, but E=MC^2 is just as valid for miniscule amounts of energy as for terajoules of energy. It is a formula expressing the ratio of mass to energy in a perfect system of conversion.
I agree with the a-bomb tests, in retrospect at least.
There are numerous ways we could destroy the Earth not involving a black hole. However, the Earth doesn't have to be destroyed for humanity to very quickly and completely die out. Imagine a virus much like HIV which is spread via personal contact, with a 10+ year latent period it could easily kill a large percentage of the population. Not every single person, but ~99% would be possible. That would destroy our civilization, you know that thing that makes us human.
I am NOT afraid of the unknown, but there is a middle ground between blindly darting through the dark assuming that since the universe hasn't killed you yet you can not die and quaking in fear at the mention of things new. It is called scientific responsibility.
the grey goo scenario IS NOT POSSIBLE because it has not happened
Given the infinitesimal fraction of the universe we can observe directly in detail, the preceding statement is a bit like, "The Chinese are not possible, because there are no Chinese in my living room."
anyone who who seriously thought a-bomb tests would ignite the atmosphere was applying as much logial brain power as those people who thought humans would suffocate at the dizzying speeds of 30mph on the early steam trains.
Yes, the idea of igniting the atmosphere was stupid. But the idea that nuclear fission was going to provide cheap, clean, limitless power was also stupid, but at one point widely believed. The idea that nanotech will be a miracle technology with no dangers might well be equally naive.
And while no one suffocated on a 19th century train travelling at 30mph, both the rate of acceleration and velocities achieved by 20th century military aircraft are capable of causing injury or death, hence closed cockpits and flight suits. The full potential of a technology is seldom immediately obvious in its early prototypes.
Being irrationally fearless is no better than being irrationally fearful.
Proud member of the Weirdo-American community.
On a related note, consider this readable account of how genetic engineering to insert IL-4 into an otherwise fairly innocuous mousepox transformed this disease to where it would effectively kill all the mice, even those mice that had been previously vaccinated to protect them against mousepox.
"Provided by the management for your protection."
Drexler *never* said that "grey goo" would consume the biosphere. What he actually said was "Dangerous replicators could easily be too tough, small, and rapidly spreading to stop - at least if we made no preparation." (emphasis mine, see Engines of Creation Chapter 11). It has been known for more than a decade that there are easy solutions to the problem of designing "safe" replicators that do not grow exponentially using strategies such as the "broadcast architecture" (in computer science terms -- you never give a replicator a copy of its own source code). [See Merkle, R. C., "Self Replicating Systems and Molecular Manufacturing", JBIS 45:407-413 (1992)].
Nor is the idea that assembly lines produce better manufacturing systems than self-replicating systems new. [See Hall, J. S., "Architectural considerations for self-replicating manufacturing systems", Nanotechnology 10(3):323-330 (September, 1999).] It is obvious that the ability to self-replicate is extra overhead when compared with assembly systems optimized for specific assembly tasks.
Finally, it was shown several years ago that we have the technology to detect out-of-control self-replicating systems (nanorobots generate heat which can be detected by existing satellite systems). [For a discussion of various scenarios read: Freitas, R. A., "Some Limits to Global Ecophagy by Biovorous Nanoreplicators with Public Policy Recommendations" (May, 2000).]
Drexler alludes to the fact that we are already in the midst of a "green goo" ("We have trouble enough controlling viruses and fruit flies.") Most people are unaware of the fact that they have more copies of foreign genomes (in the form of self-replicating bacteria) on or in their body than they have copies of their own genome. Some of these bacteria actually produce vitamins that humans use. So "goo" scenarios should not be viewed as completely negative. It is worth noting that the same methods that can be used to stop the "green goo" (e.g. heat or radiation) can be used to stop the "gray goo" if we are prepared to detect and eliminate it. One sees examples of this today as government agents circulate through the crowd waiting to view President Regan's body in Washington with biological and chemical weapons detectors. It simply comes down to understanding the hazards and being prepared to deal with them.
It is also worth noting that the design of fully self-replicating nanorobots is *not* a simple or inexpensive task. (Look at how long it took Nature to get it started...) So it is highly improbable that such abilities could be developed by rogue groups before civilized nations developed robust detection and elimination methods.
For people who want to read more details, the IOP press release is here and points to the actual paper (registration probably required).
Also, I would respectfully request before you post any responses to this note that you "go do your homework" (that will put you one up on the reporters reporting on this and allow for an informed discussion).
The primary limitation on even arbitrarily sophisticated nanotechnology which could prevent a runaway grey goo reaction is the lack of a sufficient source of energy. A nanomachine wouldn't be able to get much energy out of eating inorganic matter such as rocks because, aside from a few exceptions (coal, for example) it's mostly well-oxidized and sitting in a free-energy minimum.
It would instead get its energy from sunlight and distribute it electrically within itself. Catalyzed electrochemical reactions would break down silica-based minerals to provide more building materials.
This wouldn't allow transformation of the earth in the blink of an eye, but you'd still get rapid progress (picture nano-lichen that spreads across rock in a layer that grows thicker as underlying rock is digested). Heat of formation of SiO2 is about 14 MJ/kg, and it weighs about 2.6 T/m^3, for a decomposition energy of about 37 GJ/m^3. A perfectly efficient nanoswarm would eat into a rock face at a rate of about 0.1 m/year (given a solar duty cycle on the order of 10%). A realistic upper bound to system efficiency is on the order of 10%, giving about 1 cm/year.
So, areas could be actively protected against nano-infestation without much trouble (even with something as simple as a layer of paint), but unattended rock mass could be converted to nano-powder quickly enough to cause serious environmental problems in some situations (mountain rockfaces above the tree line sift nano-sand down on top of vegetation below, choking out plant life and lowering the tree line; lather, rinse, repeat, until what was a mountain range and foothill network becomes a desert).
This all assumes silicon-based nanomachines. Carbon-based nanomachines are more attractive from a construction point of view.
I consider disaster scenarios like this unlikely (among other things, the "desert" produced in the scenario above would quickly be seeded with vegetation, which would choke off its power supply). But, they're fun to think about.
Prince Charles is next in line to the British throne and more than likely will be the next King of England. The British Monarch has three essential rights:
Granted, Charles is not yet king, but his contribution on this issue falls more or less within his future remit (and would indicate the advice he would offer to the British Prime Minister of the day)
Whether one wants to have a (future) monarch around to give such advice is another question entirely.