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Ironically, if we look at society in another 50 - 75 years, if and when nanotech becomes feasible and public, then we'll start getting many many political and social problems altogether. Just look at how the concepts of cloning, stem cell research and abortion has torn society apart. Then imagine something as radical as nanotech. Take a step back and think about the social, economical and political reprocussions.

Oh, my god. Someone is building very small robots.......

I don't think nanotechnology is going to be on quite the same par as cloning and stem cell research. But it will have an impact.

Well, its not simply the thought that someone is building small robots, its the thought of what they can do and how the media will hype it.

Technically, with nanotech, genetic engineering will become something quite simple. Custom cures for diseases as you simply have nanomachines do search and destroy inside your body, but then that can be used in a scary way as well. Imagine nanomachines that kind of screws up and starts doing search and destroy on red blood cells. You completely redefine the meaning of biological warfare.

Its the "what if's" that the media hypes that scares people.

Quote:Original post by intrest86
1) Conservation of Energy. The nanos have to be powered somehow, and they can only perform as much work as they are powered to perform. IE, one nano can't lift you when it is powered by photons hitting it every once in a while.

There seems to be an implication here that nanomachines can only be powered by photons, which is plainly false. Remember that a strong human is quite capable of lifting another human, and that humans are made out of a combination of nanomachines and bulk matter assembled by nanomachines.

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Also, because of noise/range issues, we can expect that nanos can only communicate with so many other nanos within a certain range.

Well that's quite obviously not true.

The nanomachines in your brain cells are capable of indirectly communicating with the nanomachines in the feet. Indeed, the nanomachines in your brain cells are capable of indirectly communicating with the nanomachines in my brain cells.

There's no reason to assume that nanomachines would have a particular need to use radio communications. In fact, there's good reason to assume they'd need not to. A radio signal powerful enough to reach a controlling nanocomputer a few centimeters away could be powerful to interfere with the function of neighbouring nanomachines. Which would be acceptable until all of them want to talk to the nanocomputer.

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We already worry about dealing with the relatively small number of processors involved in the next gen game consoles, try dealing with 1000's to 1000000's of processors that have limited bandwidth to communicate with only a select group of others with. I think this would lead to some very important limitations as far as what could be done, and with what speed.

It's not as bad as you make out. There is considerable previous art for using nanomachines to build complex systems with fast response-times. It's called "life". Although it won't be at all easy, it looks like more of a problem than it really is because people have a tendency to think in terms of present-day programming languages when they think about controlling billions of nanomachines. It should be obvious that although the behaviour of a single nanomachine might be programmable with today's techniques, the behaviour of a swarm of billions of nanomachines simply can't be programmed in C++.

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Acid like actions are an example of something that require a small amount of energy, no mass, and no coordination at all.

Most 'acidlike' nanosystems would either need considerable amounts of energy (because the decomposition reaction was endothermic (e.g. reducing water to hydrogen and oxygen)) or need considerable amounts of coolant (because it was exothermic (e.g. reducing a human to its constituent compounds). Real acid works because it isn't made of tiny machines which will stop working if they freeze or melt.

A 'nanoacid' would therefore need to coordinate its actions so that heat could be transfered away from the hapless victim. An easy approach would be to let heat build up in the nanomachines, and then have them move away to a 'cooling zone' before they are rendered inoperable. Or, if you want the acid to wear itself out over time, which might be useful if it was used as a weapon, it could wait until the Dissolve-O-Trons(TM) died, and other nanomachines would move them away.

I find it quite interesting that people are concerned about control and think about a central system. However, this is plainly natural, since most computing systems started from a centralized entity or having a centralized entity. It took people computing 20+ years to go from centralized servers to the current boom in peer-to-peer applications (if not longer). Nanomachines are the ultimate peer to peer application (or distributed however you want to look at it).

There is almost no need for a centralized control system to actively control everything. You may just need a central system to give the start and stop signal and/or monitor raw material use or progress, but everything else is pretty much autonomous.

The human body was brought up as an example. The human body is nothing more than a symbiotic collection of specialized cells that work together for the survival of everyone else. How intelligence emerged is another thing, but in truth, there is no true central control. You might say the brain is in control, but it isn't one single entity either, and research has shown that the brain isn't in control of everything at all times either. Best example, your reflexes aren't actually coming from your brain. Most reflex reactions are so urgent that the signal reaches only the spinal cord and then to the first major cluster of nerves.

If termites that have no centralized control is capable of building huge vertical mounds of sand, which they use as a nest (we're looking at things up to 10 feet tall) one pebble at a time, I don't see why nanomachines can't build stuff from the ground up in the same way based on some simple autonomous rules, and maybe a little global intervention/guidance along the way.