Nanotechnology

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== In reality ==
 
== In reality ==
  
Needless to say, reality is much duller than fiction - unless you're studying and genuinely interested in it, of course. Instead of creating the tiny magic robots popularized by science fiction, current nanotechnology focuses on creating much simpler structures, such as nanoparticles that can deliver drugs to specific cells, and materials with advantageous properties.  
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Needless to say, reality is much duller than fiction - unless you like the actual science, of course. Instead of creating the tiny magic robots popularized by science fiction, current nanotechnology focuses on creating much simpler structures, such as nanoparticles that can deliver drugs to specific cells, and materials with advantageous properties.  
  
 
Better understanding of materials at nanoscale is explaining many odd things. Colloidal nano-particles of gold are red, rather than yellow as the bulk metal is - and this effect is responsible for the colours of medieval stained glass. Some of the odd properties of soot are because it contains buckyballs and nanotubes.
 
Better understanding of materials at nanoscale is explaining many odd things. Colloidal nano-particles of gold are red, rather than yellow as the bulk metal is - and this effect is responsible for the colours of medieval stained glass. Some of the odd properties of soot are because it contains buckyballs and nanotubes.

Revision as of 12:58, 12 September 2010

Drexler’s thesis is merely the source of the disease. What I’m really sick of are ding dongs trying to tell me toothpaste or golf balls is nanotech.
—Scott Locklin[1]

Nanotechnology (often referred to as "nanotech") is the art of working on materials at the nanometer (one billionth of a meter) scale, hence the name. It's materials science with "nano-" on the front because that gets funding from people who've heard of Drexler.

There are two sorts of nanotechnology: reality, and science woo.

Contents

History

The idea was first postulated by Richard Feynman and popularised by the work of science fiction K. Eric Drexler used as a Ph.D thesis. Nanotechnology fanboys — as opposed to the people who actually work with the stuff — have a habit of downplaying Feynman's origination of the idea and playing up Drexler, possibly because the latter is far more indulgent of their fantasies.

Possible uses

  • Fabrication
  • Material technology
  • Medical technology
  • Information technology
  • Food technology
  • Fuel technology

Portraying nanotechnology as a single unified technology is simplistic. More accurate would be the notion of many different technologies and industries reaching the point where "nano" level operations are of interest.

In science woo

The popular conception of nanotechnology is Drexler's concept of nanobots, like industrial robots scaled down a billion times. This is entirely made of bollocks and would violate physics, chemistry, and thermodynamics.[2][1]

That Drexler has pushed an idea which is actually impossible has not deterred nanotech fans, who get as upset as they usually do when an expert in a field they're talking about points out they're simply wrong, apparently from an emotional sunk cost fallacy.[3]

Since real scientists have entered the field of nanotechnology and started using it for things that do not defy physics, Dr. Drexler has taken to using his new favored term, "zettatechnology."[4]

In fiction

Drexler's vision of nanobots is a standard science fiction trope for magic. Applications include superhuman healing and body repair, superhuman powers, shapeshifting machines, constructing large structures at a miraculous pace,[5] self-repairing materials, instantly taking over and reprogramming any computer system[6] or even you.[7] Alternatively, a swarm of nanomachines can be a weapon eating anything in its path like locusts.[8][9]

One common version is self-replicating nanomachines, which convert any available matter into more nanomachines to replenish and bolster their numbers. If left unchecked, these machines convert everything — the so called "Grey Goo" doomsday scenario.[10] The idea of creating self-replicating machines, which was an early goal of nanotechnology, has given way to the safer and simpler approach of building larger (relatively speaking) factories that can mass-produce nanomachines, making this scenario less likely to occur in reality.[11][12]

Writers like these little things because they don't have to show and explain how they work — all you see are the results.

In reality

Needless to say, reality is much duller than fiction - unless you like the actual science, of course. Instead of creating the tiny magic robots popularized by science fiction, current nanotechnology focuses on creating much simpler structures, such as nanoparticles that can deliver drugs to specific cells, and materials with advantageous properties.

Better understanding of materials at nanoscale is explaining many odd things. Colloidal nano-particles of gold are red, rather than yellow as the bulk metal is - and this effect is responsible for the colours of medieval stained glass. Some of the odd properties of soot are because it contains buckyballs and nanotubes.

Molecular nanotechnology, which aims to engineer mechanical systems at the molecular level, is barely in its infancy. As far as the dream of assembling molecules "atom by atom" is concerned, this is even further away. So far, scientists are pretty good at arranging atoms in patterns with an scanning tunneling microscope (STM), as has been done by IBM to demonstrate STM technology and in the case of "quantum corals" that demonstrate the wave-like properties of electrons. If nanomachines are built, they will work much more like the currently-known nanomachines — antibodies and proteins and so forth.

Mechanical nanocomputers are theoretically possible, and we're getting there. So far there's a 300nm electromechanical reed relay gate.[13][14] For comparison, current computers' electronic transistors are on the order of 30nm (as of 2010).

That's not to say that this stuff isn't insanely cool. For instance, sending in a specially-designed killer molecule to cure cancer.[15] Holy crap!

It should be noted that there are examples of self replicating machines that "eat" the ground and then sense the available resources of the surrounding territory and assemble useful products, even erecting mini solar panels to assist the process as well as producing the next generation of their initial seeding mechanism, all fully automated and largely unattended. They are called things like "tomato plants".

Problems

Nanotechnology as an idea doesn't have any problems per se (especially considering that any nanotechnology that does have problems, doesn't exist), however there are problems with some of the public depictions or expectations of nanotechnology, especially if portrayed as "just around the corner" instead of part of the abstract sci-fi realm along with things like anti-gravity.

Consider the grey goo scenario. Such a scenario would require a very fast replicating machine, capable of deconstructing all kinds of material around it and creating more of itself. Said machines are often depicted abstractly yet similar to "metallic" tiny robots, complete with miniature power tools, miniature propellers/jet engines and miniature pistons, despite the fact that such technologies don't scale at that level.

Other problems with that scenario include the simple fact that metal takes a lot of energy to forge. There's a reason that life is the only successful self assembling and self replicating nanotechnology so far: because life's constituent materials are relatively easy to put together or take apart. Metal isn't. Or rock. Or plastic. Such miniature robots would not only have to find those energies but also utilize them in ways that wouldn't destroy themselves. It could be possible for nanobots to gradually assemble machines that ultimately make themselves, but at no point should it be expected that they could do so within seconds, while eating buildings. This means that everyone's favorite grey goo might in reality not be faster than life is (which, it should be noted, has actually been optimized for de-constructing/re-constructing the environment around it through billions of years of genetic algorithms) and it would be an achievement if it spread itself at the rate of mold rather than something like this.

The main practical problem with nanotechnology is the phrase being overused as funding hype for what anyone else would call material science or synthetic biology.

See also

  • Cryonics, where "but, nanobots!" is the standard answer to any objection.

External links

Footnotes

  1. 1.0 1.1 Nano-nonsense: 25 years of charlatanry (Scott Locklin, Locklin on science blog, August 25th 2010)
  2. Rupturing The Nanotech Rapture: Biological nanobots could repair and improve the human body, but they'll be more bio than bot Richard A.L. Jones, IEEE Spectrum, June 2008
  3. Cryonicists' sunk costs reasoning about Drexler's "nanotech." (Mark Plus, The Life of Man Qua Man on Earth blog, 2010-08-31)
  4. http://www.azonano.com/details.asp?ArticleID=56
  5. Total Annihilation: "It would have been too complex and time consuming to have little guys with hammers and scaffolds every time something was built in the game. It also wasn't futuristic enough. We needed something like magic, but with a thin veneer of science around it. Nanotechnology to the rescue!"
  6. wp:T-X
  7. http://memory-alpha.org/en/wiki/Assimilation
  8. wp:The Day the Earth Stood Still (2008 film)
  9. wp:G.I. Joe: The Rise of Cobra
  10. For example, the Replicators in Stargate
  11. http://nanotechweb.org/cws/article/indepth/19648
  12. http://www.crnano.org/BD-Goo.htm
  13. Babbage nanomachine promises low-energy computing (New Scientist #2573, 25 March 2010)
  14. Diego N. Guerra, Adi R. Bulsara, William L. Ditto, Sudeshna Sinha, K. Murali and P. Mohanty, A Noise-Assisted Reprogrammable Nanomechanical Logic Gate. Nano Letters, 10 March 2010, DOI: 10.1021/nl9034175
  15. This Is the Future of the Fight Against Cancer (Janet Fang, Nature, 21 March 2010 doi:10.1038/news.2010.138)
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