Ok, there's at least two broad classes of nanotechnology: nano-engineered materials and nanorobotics. They're very different, but you see a lot of
journalists confuse them, or lump them together and call them "nanotechnology".
A nano-engineered material might be, for example, an aluminum-halogen explosive or the inclusions in a metamaterial, or (strains to think of a
non-military context) the self-cleaning windows which have nano-scale titanium inclusions on the glass surface as a catalyst. You could lump nanotubes
and purpose-built buckyballs in this category too. In general, a nanomaterial
is going to be something that required very small particles of a
material, or the particles have to be not only small, but a specific shape and size, or they have a definite structure like a buckyball. Typically, a
nanomaterial is made in some sort of self-assembling process.
A lot of times when you see someone in the press babbling about 'nanotech' this is what they're talking about.
The other class of nanotechnology is nanorobotics. This is where the "grey goo" or "mataglap" issue comes in. Nanorobotics covers little machines
which can be fabricated at an incredibly small scale. Here's some links:
There's a lot of possible uses for nanorobotics, from little factories that can build whatever you'd like out of low-level raw materials to little
repair crews combing your bloodstream, building bone, killing bacteria, repairing blood vessels etc.
In 1966, a man named John von Neumann published a book called "The Theory of Self-Reproducing Automata" based on work he began back in the
A fast aside here...you guys should concentrate more on Neumann than you do on Tesla. His own contemporaries stated that he was an alien who
had studied humans and learned to impersonate them perfectly. He's also tied into half the stuff you guys ruminate about on ATS. He is uber creepy,
lots and lots of projects associated with him you wouldn't believe, but I've never seen any CT's on him. JvN is a motherlode of material and leads.
You guys are missing a big bet.
I have a little bell going off that tells me that Tsiolkovsky was mixed in somehow with self-reproducing machines but can't find it.
Anyways, the concept was this. If you wanted to build a moonbase, you could do it by launching hundreds of ships containing men, living environments,
machines, power plants, raw materials and so on. Very expensive, very dangerous.
It would be much simpler if you could simply deliver machines that could do the task, for then you could leave the support systems for humans behind.
But that's still a lot of machines. Better still, if you could send a robot factory that would land on the moon and manufacture the robots you need
to build the moon base out of materials you could get from the surface. But you're still limited in how fast you can build the base, because you
only have one "robot factory" to churn out all the robots you'd need.
So Neumann proposed that you could deliver a single tiny robot to the surface. Instead of building other task oriented robots such as graders,
backhoes, smelters etc, it would be very general purpose and modular, capable of being all these things perhaps, or of constructing them as needed.
But what this robot did was first start replicating itself.
The seed robot would construct millions of copies of itself, as many as needed, out of raw materials on the surface. It would be capable of using
solar energy to disassemble any raw ore to its constituent elements and rearrange them to form duplicates of itself. When there were enough
"makers", they would fan out and differentiate, aggregating into the different machines needed to construct the moonbase, or constructing special
purpose machines as necessary. Once there were enough duplicates, like the cells in your body, they could come together to form nearly any machine you
might need. To construct your moonbase, you'd only need to deliver a seed to the target and wait. The seed might not be any bigger than a large
You may have seen something like this on "Stargate": the replicators. At first they're making little scrabble tiles that can group to form "bugs"
or even hyperspace engines but in later episodes you get "human form replicators" made out of cell-sized machines. That's the general idea, only
not that they're so smart. The idea is to have them make robot bulldozers instead of evil bad guys. Think of them as robot stem cells.
But here's where the rub comes in. These things are pretty complex, so there's all sorts of possibilities of having coding bugs. They also live in a
rough environment, lots of UV and radiation, and it's really possible for a few bits to flip in the code due to impact damage. Maybe you could get
"mutations" that your self-repair facilities (if you had them) wouldn't catch.
So let's say out of your millions of little cell-sized makers, one catches a high-speed solar proton right in the old noggin and it takes out the
self-repair algorithm. The maker can't tell that it's been damaged because that's been knocked out, and therefore it doesn't self-destruct or
repair the damage. It keeps reproducing itself, and the daughter makers carry the damage of the adult. They're still working but don't have the
capability to tell if they've made an error. You get a few generations, and another mutation occurs. This one is in the code that tells the maker
when to stop reproducing and start forming into an ore smelter or solar cell factory. It thinks it needs to keep on churning out daughters. So it
does. And it's doing it very rapidly, that's the beauty of a Neumann machine.
You see, they replicate exponentially. You start with one, then two, then four, eight and so on. Once you get one with an error that can't tell when
to stop reproducing itself, it can transform the entire crust of the Moon into brain damaged copies of itself within a relatively short time, limited
by the usefulness of the raw materials and the rate of energy input to the system.
This is the so-called "gray goo" scenario, you get a non-detected error in an exponentiating machine which causes it to stay in the replication
phase forever. It turns all the raw material of the planet into useless malfunctioning copies of itself, or "gray goo'.