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Programmable Matter: The New Alchemy
Anonymous Kamath writes "IEEE Spectrum recently published an interview with aerospace-engineer-turned-science-fiction-author Wil McCarthy who's just written his first non-fiction book "Hacking Matter: Levitating Chairs, Quantum Mirages and the Infinite Weirdness of Programmable
Atoms" proposing the application of quantum dot technology on a large scale
thereby allowing one to control properties of materials at will. Another science fiction author laid down the principles of geostationary satellite communication
half a century ago."
Wil Mccarthy's web site
Tons of interesting info...
Why do I h8 apple?
foobar/foobar worked for me
registration/sucks
Really, I registered a free account with this combo.
'He was a dreamer, a thinker, a speculative philosopher... or, as his wife would have it, an idiot.' - Douglas Adams
The New Alchemy
Could semiconductor technology do for material science what it has for computing?
Imagine a solid wall that, as the occasion demands, becomes completely transparent or transforms on one side into a giant video screen while the other side becomes either a solar panel or a heat pump that cools a room on a hot day. This is the promise of programmable matter--and it could make the technology revolution wrought by semiconductors to date look like a warm-up for the main act.
The idea of programmable matter began to seep into the popular consciousness in recent years through the works of aerospace-engineer-turned-science-fiction-author Wil McCarthy [right], who dubbed the new material wellstone in novels like The Collapsium (Del Rey, 2000). Now McCarthy has written his first nonfiction book about programmable matter, Hacking Matter: Levitating Chairs, Quantum Mirages and the Infinite Weirdness of Programmable Atoms. Associate Editor Stephen Cass talked to him about this bleeding-edge technology and how McCarthy himself is helping to transform science fiction into science fact.
What is programmable matter?
Programmable matter is fundamentally a solid-state technology--something that can change its optical, physical, magnetic, or electrical behavior without any moving parts except for electrons or photons. In that sense, there are certain things now that already qualify as programmable matter, like an LCD [liquid-crystal display] screen. This is an assembly of devices, but you can also look at it as carefully arranged material that has the interesting property of changing color under electrical stimulation. By adjusting quantum dots instead of pixels, you can make artificial atoms and adjust a lot more than just the color of the material.
What are quantum dots and how do you use them to make artificial atoms?
A natural atom is a particular means for confining electrons--the positively charged nucleus gathers electrons around it and doesn't let them escape. By confining the electrons, you force them to behave as standing waves. And those standing waves are responsible for nearly all the chemical, electrical, and optical properties that we associate with atoms.
But you don't have to have an atomic nucleus to get that sort of behavior out of electrons; you just have to confine them in a small space. There are a lot of ways to do this. One way is to use the standard techniques of semiconductor chip design to create junctions that will herd electrons into an area of choice, known as a quantum dot. Once confined, the electrons will form a structure known as an artificial atom. With artificial atoms, unlike natural atoms, there is no reason why you can't pump electrons in and out and change their characteristics dynamically, making them programmable.
But if these programmable atoms are buried in a semiconductor substrate, how do they interact with anything? How do you make the entire material behave like it's made out of, say, gold?
With programmable atoms in a substrate, what you are really doing is creating controlled impurities--dopant atoms--so the properties of your semiconductors are going to be very important in determining the final properties of the programmable substance. You can get a very high level of doping with a properly designed quantum dot array and overwhelm the normal behavior of the semiconductor. You can never ignore the fact that the semiconductor is there, but you can change its properties almost beyond recognition.
So would you have to combine different types of artificial atoms to end up with a material whose net behavior is like that of gold?
Probably. An artificial atom of gold-- pseudo-gold--is almost certainly going to be a lot larger than an atom of natural gold. One consequence of this is that its absorption and reflection spectrum will be redshifted, because the electrons are less tightly bound so they will be at lower energies. So even if you could somehow have atoms of pseudo-gold without any substrate, they'd be
No, it just means you have to wait a few minutes until someone posts the content
Technoli
The New Alchemy
Could semiconductor technology do for material science what it has for computing?
Imagine a solid wall that, as the occasion demands, becomes completely transparent or transforms on one side into a giant video screen while the other side becomes either a solar panel or a heat pump that cools a room on a hot day. This is the promise of programmable matter--and it could make the technology revolution wrought by semiconductors to date look like a warm-up for the main act.
The idea of programmable matter began to seep into the popular consciousness in recent years through the works of aerospace-engineer-turned-science-fiction-author Wil McCarthy [right], who dubbed the new material wellstone in novels like The Collapsium (Del Rey, 2000). Now McCarthy has written his first nonfiction book about programmable matter, Hacking Matter: Levitating Chairs, Quantum Mirages and the Infinite Weirdness of Programmable Atoms. Associate Editor Stephen Cass talked to him about this bleeding-edge technology and how McCarthy himself is helping to transform science fiction into science fact.
What is programmable matter?
Programmable matter is fundamentally a solid-state technology--something that can change its optical, physical, magnetic, or electrical behavior without any moving parts except for electrons or photons. In that sense, there are certain things now that already qualify as programmable matter, like an LCD [liquid-crystal display] screen. This is an assembly of devices, but you can also look at it as carefully arranged material that has the interesting property of changing color under electrical stimulation. By adjusting quantum dots instead of pixels, you can make artificial atoms and adjust a lot more than just the color of the material.
What are quantum dots and how do you use them to make artificial atoms?
A natural atom is a particular means for confining electrons--the positively charged nucleus gathers electrons around it and doesn't let them escape. By confining the electrons, you force them to behave as standing waves. And those standing waves are responsible for nearly all the chemical, electrical, and optical properties that we associate with atoms.
But you don't have to have an atomic nucleus to get that sort of behavior out of electrons; you just have to confine them in a small space. There are a lot of ways to do this. One way is to use the standard techniques of semiconductor chip design to create junctions that will herd electrons into an area of choice, known as a quantum dot. Once confined, the electrons will form a structure known as an artificial atom. With artificial atoms, unlike natural atoms, there is no reason why you can't pump electrons in and out and change their characteristics dynamically, making them programmable.
But if these programmable atoms are buried in a semiconductor substrate, how do they interact with anything? How do you make the entire material behave like it's made out of, say, gold?
With programmable atoms in a substrate, what you are really doing is creating controlled impurities--dopant atoms--so the properties of your semiconductors are going to be very important in determining the final properties of the programmable substance. You can get a very high level of doping with a properly designed quantum dot array and overwhelm the normal behavior of the semiconductor. You can never ignore the fact that the semiconductor is there, but you can change its properties almost beyond recognition.
So would you have to combine different types of artificial atoms to end up with a material whose net behavior is like that of gold?
Probably. An artificial atom of gold-- pseudo-gold--is almost certainly going to be a lot larger than an atom of natural gold. One consequence of this is that its absorption and reflection spectrum will be redshifted, because the electrons are less tightly bound so they will be at lower energies. So even if you could somehow have atoms of pseudo-gold without any substrate,
Technoli
http://www.spectrum.ieee.org/WEBONLY/resource/apr0 3/book.html
ok... I got it from some search engine...
From an earlier post:
"It should be noted that Tsiolkovsky was talking about geosynchronous orbits around 1900, and radio engineer George O. Smith wrote about communication satellites in "QRM Interplanetary" in 1942. However, Smith's communication satellites/stations were generally placed at Trojan points in order to give line-of-sight between planets around the sun (hence the name of the novel/story collection "Venus Equilateral"). Of course, no one made a movie of one of Smith's books, so everyone forgets him..."
I have nothing against Arthur C. Clarke, but credit should go where it is due. And when life on Europa or diamonds on Jupiter are discovered, THEN it will be a prediction. Until then, it's called "speculation".
Greg Bear has had an idea along these lines,
in his book "Moving Mars".
Thought you guys might find this interesting as well, since the page is gone....
t ml
http://pm.bu.edu/
http://www.wilmccarthy.com/pmfaq.htm
http://www.wired.com/wired/archive/9.10/atoms.h
Arthur C. Clarke was NOT the first person to propose relay satellites. He adapted the idea of a geosynchronous satellite from an older story by an obscure SF author whose name escapes me now. The author wrote a story describing a relay station put up on an asteroid to act as a bridge between Earth and Venusian colonies when the sun was in the middle. Essentially, the same concept Clarke used.
"Don't bother me with that pocket calculator stuff" - Deep Thought
. . . I think. The book might have been _Venus Equilateral_.
A very elderly Smith attended one of the first SF conventions I went to. What I best remember about the con was the shameful way a young snot of a fan treated him when he was given an honorary spot on a panel.
One of the requirements for a valid patent is that the patent must disclose sufficient information so that someone well-versed in the "prior art" can actually construct the device.
If the device he has patented can't be constructed yet, the patent is invalid, since it's obvious that he hasn't disclosed sufficient information to allow it to be constructed.
Someone can try to patent stuff that isn't realizable for years and years, but they don't end up with a valid patent. This is one of the (few) patent regulations that actually make sense.
There are several stable lead isotopes, so I'm sure someone can come up with a pair of reactions that turn one of those isotopes into 197Au, although getting rid of three protons is decidedly inconvenient - far harder than getting rid of two or four. But you'd probably lose most of the lead to other reactions, and it would indeed be a ridiculous waste of money. Gold is cheap.
Yes, I mean that. It's all relative, of course. That gold is expensive is 'common knowledge'. Still, many people realise that platinum and iridium are more expensive. Some fraction of them realise the value of other rare, useful elements - such as tantalum.
What's really expensive is isotopically enriched or pure material. (Weapons-grade uranium is a (cheap) example of an enriched material.) Such as the 196Hg that the previous poster mentioned. My PhD work required 176Lu, which we purchased 4 milligrams of stuff enriched to 50%, at about US$1600 per milligram (From memory of four years ago.) It's not the most expensive out there, either ... What price does Gold fetch per ounce (30 grams?) There is only one isotope of gold, and it's relatively easy to chemically purify, and relatively common on the earth's crust. We make targets of it all the time - it's great for calibrations - the lab occasionally sends visitors home with a few cents worth of gold foil on their thumbnails.
Possibly the most valuable batch of nuclei in the world is a target made of the 16+ isomeric form of 178Hf - a truly microscopic quantity of material made by herculean effort at a big laboratory. The enrichment is something tiny like 3%.
Other materials that make gold look cheap are things like carbon nanotubes. Bucky-balls extended into pipes. There have been massive improvements in manufacturing processes - I think the cost of bucky-tubes is now comparable with that 176Lutetium I was talking about. As for the programmable materials the article refers to - they're going to start out vastly more expensive still, and it'll take a long time before the cost drops to near modern silicon technology - and you don't build your walls from RAM, do you? Don't expect to replace bricks with programmable materials, at least in your lifetime. Be impressed if artificial-atom materials get cheap enough to be used in common consumer goods.
Rachel