It'll all go well until they try and unionize. Then, the bulldozers will be unleashed.
Posted on 12/04/2005 12:17:14 AM PST by sourcery
It has been 20 years since the futurist Eric Drexler daringly predicted a new world where miniaturized robots would build things one molecule at a time. The world of nanotechnology that Drexler envisioned is beginning to come to pass, with scientists conjuring new applications daily.
Now Salvatore Torquato, a Princeton University scientist, is proposing turning a central concept of nanotechnology on its head. If the theory bears out – and it is in its infancy -- it could have radical implications not just for industries like telecommunications and computers but also for our understanding of the nature of life.
Torquato and colleagues have published a paper in the Nov. 25 issue of Physical Review Letters, the leading physics journal, outlining a mathematical approach that would enable them to produce desired configurations of nanoparticles by manipulating the manner in which the particles interact with one another.
This may not mean much to the man on the street, but to the average scientist it is a fairly astounding proposition.
Image: "Triangle Lattice."
"In a sense this would allow you to play God, because the method creates, on the computer, new types of particles whose interactions are tuned precisely so as to yield a desired structure," said Pablo Debenedetti, a professor of chemical engineering at Princeton.
The standard approach in nanotechnology is to come up with new chemical structures through trial and error, by letting constituent parts react with one other as they do in nature and then seeing whether the result is useful.
Nanotechnologists rely on something called "self-assembly." Self-assembly refers to the fact that molecular building blocks do not have to be put together in some kind of miniaturized factory-like fashion. Instead, under the right conditions, they will spontaneously arrange themselves into larger, carefully organized structures.
As the researchers point out in their paper, biology offers many extraordinary examples of self-assembly, including the formation of the DNA double helix.
But Torquato and his colleagues, visiting research collaborator Frank Stillinger and physics graduate student Mikael Rechtsman, have taken an inverse approach to self-assembly.
"We stand the problem of self-assembly on its head," said Torquato, a professor of chemistry who is affiliated with the Princeton Institute for the Science and Technology of Materials, a multidisciplinary research center devoted to materials science.
Instead of employing the traditional trial-and-error method of self-assembly that is used by nanotechnologists and which is found in nature, Torquato and his colleagues start with an exact blueprint of the nanostructure they want to build.
''If one thinks of a nanomaterial as a house, our approach enables a scientist to act as architect, contractor, and day laborer all wrapped up in one," Torquato said. "We design the components of the house, such as the 2-by-4s and cement blocks, so that they will interact with each other in such a way that when you throw them together randomly they self-assemble into the desired house."
To do the same thing using current techniques, by contrast, a scientist would have to conduct endless experiments to come up with the same house. And in the end that researcher may not end up with a house at all but rather – metaphorically speaking -- with a garage or a horse stable or a grain silo.
While Torquato is a theorist rather than a practitioner, his ideas may have implications for nanostructures used in a range of applications in sensors, electronics and aerospace engineering.
"This is a wonderful example of how asking deep theoretical questions can lead to important practical applications," said Debenedetti.
So far Torquato and his colleagues have demonstrated their concept only theoretically, with computer modeling.
They illustrated their technique by considering thin films of particles. If one thinks of the particles as pennies scattered upon a table, the pennies, when laterally compressed, would normally self-assemble into a pattern called a triangular lattice.
But by optimizing the interactions of the "pennies," or particles, Torquato made them self-assemble into an entirely different pattern known as a honeycomb lattice (called that because it very much resembles a honeycomb).
Why is this important? The honeycomb lattice is the two-dimensional analog to the three-dimensional diamond lattice – the creation of which is somewhat of a holy grail in nanotechnology.
Diamonds found in nature self-assemble the way they do because the carbon atoms that are the building blocks of diamonds interact with each other in a specific way that is referred to as covalent bonding. This means that each carbon atom has to bond with exactly four neighboring atoms along specific directions.
One surprising and exciting feature of the Princeton work is that the researchers were able to achieve the honeycomb with non-directional bonding rather than covalent, or directional, bonding.
"Until now, people did not think it was possible to achieve this with non-directional interactions, so we view this as a fundamental theoretical breakthrough in statistical mechanics," Torquato said. Statistical mechanics is a field that bridges the microscopic world of individual atoms with the macroscopic world of materials that we can see and touch.
To create the honeycomb lattice, the researchers employed techniques of optimization, a field that has burgeoned since World War II and which is essentially the science of inventing mathematical methods to make things run efficiently.
Torquato and his colleagues hope that their efforts will be replicated in the laboratory using particles called colloids, which have unique properties that make them ideal candidates to test out the theory. Paul Chaikin, a professor of physics at New York University, said he is planning to do laboratory experiments based on the work.
The paper appearing in Physical Review Letters is a condensed version of a more detailed paper that has been accepted for publication in Physical Review E and which will probably appear sometime before the end of the year.
Torquato said that he and Stillinger initially had trouble attracting research money to support their idea. Colleagues "thought it was so far out in left field in terms of whether we could do what we were claiming that it was difficult to get funding for it," he said. The work was ultimately funded by the Office of Basic Energy Sciences at the U.S. Department of Energy.
"The honeycomb lattice is a simple example but it illustrates the power of our approach," Torquato said. "We envision assembling even more useful and unusual structures in the future."
Ping
ping for later
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Things that make you go hmmm....
Interesting, but we'll have to wait and see.That said, nanotech is incredibly interesting. Maybe in our lifetimes, we'll see the collapse of entire commodity markets because of the cheap nano-versions of certain things. That would be interesting.
About 250 years ago the average life expectancy was 35 years old. Humans started "playing God" many centuries ago.
Man already tried to play God once. It was called the Tower of Babel, and we know what happened there.
Basically, this means that there is a search space of many possible configurations. Each configuration can be represented as a kind of potential well. Some well is deeper and wider than others, while others are narrower and smaller. Most of the time, we get the configuration with the deeper and wider potential wells. However, we love to get the configuration associated with a narrower and smaller well, which is hard to get to by randomly exploring the search space, which is what traditional method is about. You need to tweak the system in a certain way to push it into a desired well.
Still, this is hardly like building a house based on a blueprint. It is more like navigating a car, with a partially working steering wheel, into a desired pit, avoiding the biggest and widest pit and many others which you are not interested in.
Great! Now we can have that transparent aluminum Scotty talked about. Or at least nanophase aluminum.
Sounds like someone there is thinking clearly..
Consider atomic energy, and custom designed nuclear fuel rods, with a safety factor added by seperating uranium or plutonium atoms with something like carbon (or silicon) nanotubes..
Then consider those carbon (or silicon) nanotubes are constructed to have an inner diameter of say, the size of a hydrogen atom..
You could now feed hydrogen into a nuclear reaction on the atomic level... One hydrogen atom at a time.. ( with several billion individual hydrogen feeder tubes being controlled at once.. )
This could be a crude sort of fusion reactor..
The fission reactor providing an energy source as a "starter" much like a diesel engine..
A physicist could probably tear this idea apart in a couple of minutes..(seconds) but I will revel in my genius for the moment.. ;o)
Reading this reminds me of Dembski's "The Design Inference." Of course, this current version has as its primal source Man and not some Big Statistician in the Sky. But of course man sprang from nothingness via the big bang which itself was a physical anomaly since the galaxies or universe is and always was.
I believe there is a feminine conspiracy..
I can't reveal it here, publicly..
But I call it, " Schroedinger's Wife "..
How about this stuff now?
A ceramic research lab in Dresden, Germany, has developed transparent Alumina by subjecting fine-grained (I'm guessing extremely fine-grained) aluminum to a whopping 1200 degrees Celsius ...the result of which is amazingly light but three times tougher than hardened steel of the same thickness, and it's see-through.
http://www.rense.com/general20/transparentalum.htm
DK
Fascinating, thanks for the post.
I revel in mine every day until my wife gets up.LMAO
I wonder how expensive it would be, on a large scale, to simulate the atomic structure of pure gasoline?
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