Future Of Nano Technology Biotechnology Shape example essay topic

Yorktown Heights, N.Y., April 27, 2001... IBM scientists developed a breakthrough transistor technology that could preview how computer chips can be made smaller and faster than what is currently possible with silicon. As reported in the April 27 issue of the journal Science, IBM researchers have built the world's first array of transistors out of carbon nanotubes -- tiny cylinders of carbon atoms that measure about 10 atoms across, are 500 times smaller than today's silicon-based transistors and are 1,000 times stronger than steel. The breakthrough bypasses the slow process of manipulating individual nanotubes one-by-one, and is more suitable for a future manufacturing process.

This achievement is an important step in finding materials that can be used to build computer chips when silicon-based chips cannot be made any smaller -- a problem chip makers are expected to face in about 10-20 years. "This is a major step forward in our pursuit to build molecular scale electronic devices", said Phaedon Avouris, lead researcher on the project and manager of IBM's Nanoscale Science Research Department. "Our studies prove that carbon nanotubes can compete with silicon in terms of performance, and since they may allow transistors to be made much smaller, they are promising candidates for a future nano electronic technology". Using Carbon Nanotubes as Transistors in Chips Depending on their size and shape, the electronic properties of carbon nanotubes can be metallic or semiconducting. The problem scientists had faced in using carbon nanotubes as transistors was that all synthetic methods of production yield a mixture of metallic and semiconducting nanotubes which "stick together" to form ropes or bundles.

This compromises their usefulness because only semiconducting nanotubes can be used as transistors; and when they are stuck together, the metallic nanotubes overpower the semiconducting nanotubes. Beyond manipulating them individually, a slow and tedious process, there has been no practical way to separate the metallic and semiconducting nanotubes -- a roadblock in using carbon nanotubes to build transistors. The IBM team overcame this problem with "constructive destruction", a technique that allows the scientists to produce only semiconducting carbon nanotubes where desired and with the electrical properties required to build computer chips. New Technique: "CONSTRUCTIVE DESTRUCTION" The basic premise of "constructive destruction" is that in order to construct a dense-array of semiconducting nanotubes, the metallic nanotubes must be destroyed. This is accomplished with an electric shockwave that destroys the metallic nanotubes, leaving only the semiconducting nanotubes needed to build transistors. Here is how it works: 1.

The scientists deposit ropes of "stuck together" metallic and semiconducting nanotubes on a silicon-oxide wafer, 2. Then a lithographic mask is projected onto the wafer to form electrodes (metal pads) over the nanotubes. These electrodes act as a switch to turn the semiconducting nanotubes on and off, 3. Using the silicon wafer itself as an electrode, the scientists "switch-off" the semiconducting nanotubes, which essentially blocks any current from traveling through them, 4.

The metal nanotubes are left unprotected and an appropriate voltage is applied to the wafer, destroying only the metallic nanotubes, since the semiconducting nanotubes are now insulated, 5. The result: a dense array of unharmed, working semiconducting nanotube transistors that can be used to build logic circuits like those found in computer chips. Moore's Law states that the number of transistors that can be packed on a chip doubles every 18 months, but many scientists expect that within 10-20 years silicon will reach its physical limits, halting the ability to pack more transistors on a chip. Today, chip makers are constantly battling to make the channel length in transistors smaller and smaller. The channel is the path where data travels from one place to another inside chips. The IBM team has successfully used carbon nanotubes as the channel in the transistors they have built.

Transistors are a key building block of electronic systems -- they act as bridges that carry data from one place to another inside computer chips. The more transistors on a chip, the faster the processing speed, indicating why this advance by IBM scientists could have a profound impact on the future of chip performance. Related Carbon Nanotube Work at IBM In the same report, the IBM scientists show how electrical breakdown can be used to remove individual carbon shells of a multi-walled nanotube one-by-one, allowing the scientists to fabricate carbon nanotubes with the precise electrical properties desired. The report also shows how the scientists fabricate field-effect transistors from carbon nanotubes with any variable band-gap desired. In parallel studies of carbon nanotubes, IBM researchers have been working to improve the electrical characteristics of individual nanotube transistors. The unpublished data from these studies show that if the carbon nanotubes are scaled up to the size of today's silicon-based transistors, the performance would be the same.

This proves that the smaller carbon nanotube transistors should allow for Moore's Law to continue on its path when silicon cannot be made any smaller. The report on this work is published in Science, Vol. 292, Issue 5517, April 27, 2001. The authors of the report "Engineering Carbon Nanotubes and Nanotube Circuits Using Electrical Breakdown" are Phaedon Avouris, of IBM's T.J. Watson Research Laboratory in Yorktown Heights, N.Y., Philip G. Collins, formerly of IBM, now with Covalent Materials in Emeryville, California, and Michael S. Arnold, an IBM intern from the University of Illinois. Selective breakdown of a multi-walled carbon nanotube and the building of nanotube transistors See "Constructive Destruction" Quicktime animation Read further scientific analysis Visit Nanotubes project page Get Carbon Nanotube Publications March, 2002 Nano-technology Poised for First (But Not Last) Optical Application Following more than 20 years of extensive research, nano-technology is about to make a significant impact in the telecommunications industry, with fiber-optic technology becoming its first "poster child".

What was once considered science fiction in films like "Fantastic Voyage" is being commercialized as optical subcomponents, or sub wavelength optical elements (SOEs). First out of the gate with commercial nano-technology products in any industry sector appears to be NanoOpto Corp., a Somerset, NJ-based startup with proprietary nano-technology for designing and manufacturing components for optical networking. Founded in mid-2000 and based on 20 years of multimillion-dollar research in nano-photonics and nano-manufacturing, the company has already shipped prototype components to prospective customers for testing. Nano-photonics sees the light These SOEs take advantage of the physical principles that apply in the interaction of light and structures with dimensions far smaller than the wavelength of the light.

With structural dimensions on the order of tens or a few hundreds of nanometers (hence "nano-technology"), the effects of reflection, refraction, and diffraction are highly localized and governed by a blend of classical optical and quantum effects. "Because of the novel interaction between SOEs and light, large optical effects are realized on a very small scale", says Hubert Kostal, vice president of marketing and sales for NanoOpto. "In general, this allows a size reduction for the integrated component using the SOE and can also allow a reduction in the number of subcomponents required". The advantages can be seen in the use of SOEs for polarization management.

When light is incident on an SOE polarization beam splitter, for example, one polarization passes through and the other and is reflected back, creating a 180-degree separation in the space of less than a millimeter. In a number of optical-component applications where each polarization must be processed independently, that can result in a much more compact integrated optical component. Also, because of the scale of the nano-structures used, SOEs can exhibit a broad acceptance angle to simplify integration and alignment, allowing both architectural flexibility and lower tolerances in the manufacturing process. Proof in nano-technology Nano-structures and their capabilities have undergone extensive research over two decades at several universities, including Princeton University, the University of Minnesota, and Harvard University. For telecom applications, the two key breakthroughs were in gaining a deeper understanding of the usable effects of interactions between light and nano-structures and devising methods to reliably and repeatedly manufacture those nano-structures. These breakthroughs opened the door for adoption in a major industry: optical communications.

"While most of the research work using nano-structures is being done in the biomedical field and consumer electronics areas, the first commercial production of what many believe is the next 'S' curve in the component and subcomponents fabrication area is going to be for subcomponents in the fiber-optic business", says Peter Bernstein, president of Infonautics Consulting Inc., a research-analyst firm in Ramsey, NJ. "Thus, the fiber-optic industry is going to be the proof for the entire field of nano-based technologies". This revelation, says Bernstein, is creating both excitement and challenges for companies like NanoOpto. The communications industry will likely be highly scrutinized in how it harnesses and leverages the potential of such a disruptive technology. But there are benefits beyond size-cost and power consumption are always high on the list for the acceptance of any new telecom technology.

SOEs create the opportunity for integrated optical components to be built with much smaller dimensions. That equates to lower integration costs, smaller footprints, and less power consumption for equipment manufacturers. On a more immediate level, because of the simplicity of their integration, the use of SOEs can result in significant time savings and cost reductions in the manufacture of existing integrated optical components. "Some typical products on the radar screen for telecommunications applications would include polarization management equipment, filters, and photo detectors", says NanoOpto's Kostal. "SOEs are a platform technology that can be rapidly and easily adapted to numerous customized applications".

Increasing popularity As NanoOpto leverages its "first mover" advantage in commercializing SOEs and related technologies, the benefits of nano-photonics are sufficiently revolutionary to expect more companies to follow. In fact, Pirelli (Milan, Italy) recently announced a five-year alliance with the Massachusetts Institute of Technology to work on research and production of optical components for telecommunications based on nano-technologies. The company will invest $2 million in the initial year's research. The premise behind the agreement is that by reducing costs through miniaturizing components, the technology can evolve into a highly successful and profitable business.

The fiber-optic industry may be on the threshold of attainable miniaturization of optical-component products that pack so much functionality into very small spaces with great performance and lower costs that the vision of true end-to-end fiber in the access plant of the communications network will now be possible. "The rapid adoption of nano-based optical components could, in fact, be the final nail in the coffin for continued copper life-extension technology-this is that big a revolution in price performance", says Infonautics's Bernstein. "Gigabits to the home on all-optical networks at reasonable prices are finally no longer pipe dreams or light years away". Robert Pease Lightwave. com Back to top Introduction In these pages you will the complete picture of nano technology as I see evolving. You must read my vision statement in order to understand the whole of a vision I see that will bring nano technology to the forefront of commercial and everyday usage starting in year 1997. Very often, people will talk about nano technology, mixing it with amazing science fiction and even more amazing science facts and very often they get completely lost in the rhetoric.

The information you will find here is not about that kind of rhetoric. What we are discussing here is the complete pathways to real applied nano technology. The difference is similar to holding up a Joules Verne novel at the Wright brothers after they had made their first flight and insisting that it was in there all along!! You could imagine how many red faces will stare back at you if you were to do that - and you will find exactly the same thing here. The information you will find here is in a similar state of flux and excitement as when the Wright brothers made their first leap and I would urge you not to make that mistake of waving past works of reference here which are at best optimism carried to its extreme and at worst great works of fickle d science fiction. Almost nothing is borrowed from what has been done before and it will be a complete mistake if you tried to apply any of what has been done to this new technology - because it does not build on the same foundations of what is understood to be nano technology (here in the year of 1996).

This sounds like a complete dismissal of the visionary pioneers of nano technology - and indeed it is to a large extent. There is no pretense here that is what is on offer is in any way related to what has been because it is years ahead, more advanced, realistic and deliverable in a shorter time period. The fundamental base line of understanding, objectives, axioms, and requirements are all different. This technology uses completely different parameters in order to progress from one step to the next. Also, in order to progress, it is not dependent fundamentally on any of the work that has been done before. Its not dependent on nano chemistry, nano engineering, STM, atomic force microscopes or any of what we take granted today as tools found in a nano lab.

If you make the mistake of under estimating what is on offer here or try to perform comparisons, then you will ultimately fail to comprehend anything that is on offer here and deny yourself the chance to participate in a truly global new revolution that is going to sweep aside the old manufacturing order and replace it with something completely new. The promises of nano technology and a great deal more is on offer here so if your subject speciality is just nano technology you won't be able to appreciate the scale, magnitude and scope of the technologies presented here. You need to understand robotics, you need to understand fractal mechanics, you need to understand nano technology, you need to understand mechatronics (the melding of Artifical Intelligence and electromechanical machines) and you need to understand computer operating systems before you can comprehend this technology in its entire and satisfying wholesome extent. What you get to view here is one of the most intellectually satisfying technology that answers all your desires for material wants. There is nothing that this machine will not do for you if it is related to manufacturing and making things happen. In other words, what is offered here is a completely new and different branch of science which not only reaches into the nano technology dimensions but also into the micro, macro and cosmic scales with ease - the likes of which does not exist in text books or science fiction all in the same place and at the same time in the same book.

It comes with its own rules about implementation, what is accomplish able, what is not desirable and very specific detailed implementation routes for all scales. Unlike current state of nano technology, there are no gaps in detail all the way from large scale to nano metre scale. There is no waffle, no noise and no rhetoric to fill up gaps between what is possible and what is desirable. There is no leaps of faith, or futurists dreams here.

There is only what we know and understand and what we need to do to get to the final destinations. Photolithography Further miniaturisation using photolithography can shrink the robotic cubes to micron and sub-micron dimensions where they function identically to that of the large scale. We still use the same computer software as the larger scales because as said before the robotic cubes have a minimal controller that listens to instructions sent to which are to move left, right, forward, backward, up, down, attach, detach and "what's your address"? Anything else that it does not understand is ignored or passed onto tools that may be attached. What is important at the smaller scales? At the smaller scales, self repair, locomotion (how to move) and operator control is all too important which nanotechnology as researched today all around the world in labs cannot deliver.

Fractal shape changing robot technology can deliver real millimetre, micron and nanotechnology devices. Shape changing robot technology is not dependent on fundamental advances in chemistry (!) to deliver nanotechnology devices. Shape changing robots are capable of self miniaturisation and self assembly which a good reason why it can go down all those scales with much greater ease than any other technology before it. Chip manufacture Shape changing robots have to start somewhere in the sub millimetre world and failing medical engineering, the most likely place it could start is in the chip manufacturing business. Looking at the figure above we should ask what is this tiny robot doing on this chip?

Well it could be laying tracks, it could be taking minute probes to individual circuits, it could be placing and wiring up chip modules. It could also be laying the photomask element by element as hinted below: - Extreme Fidelity In Mask Production The shape changing robot could take tiny slivers of metal and lay them down over a flat surface and weld them together to make photomasks with fantastic fidelity. Photomasks are produced on multi-million dollar steppers with extremely precise optical equipment. All this could be thrown away with technology that costs a tens of thousands of dollars (when mass produced) to produce photomasks several metres square!! The robots simply weld together plates and if these plates also have on them the grooves which allows them to be picked up, then the entire mask can be picked up even if several metres wide by fractal arms that reach down to the small slivers of metal. Implications of large photomask technology Shape changing robots will bring in the era of extremely large photomasks and with it possibilities such as wall to wall flat TV sets and building that could be built with exteriors that are at best described as TV sets.

These building will be able to change colours, display logo's of the owners, display shop signs, etc with low overheads compared to using standard paint technology. Large masks could see the deliverance of enormous computers with absolutely enormous integration, the likes of which we are never accustomed to. In the future computers with everything will be shipped and they could be hundreds of layers sandwiched together to make something that looks like a motherboard. Its more than likely the board contains the display and a touch pad to make it into a truly portable high performance supercomputer tablet. It could be aligning a photo mask which it had made earlier, it could be inspecting the surface finish, it could be taking probes into the middle of a chip and testing in situ the electronics and its functionality, it could be locally repairing a chip or it could be building more of itself! In making wafer level masks, the shape changing robots can easily be used to weld together sub micron sized plates (made from chopped extrusions) to make a wafer mask with resolution below 0.1 micron for direct exposure to a molecular beam to develop sub micron devices directly rather than go through several indirect processes of photo etching.

By extending the technique, we could probably end up with quantum dots and single electron devices where passive structures measuring nano metres are able to act as transistors by virtue of the huge interaction that electrons experience when travelling through narrow structures. The beauty of this technology is that it does not involve any nano technology chemistry or polluting chemicals, it has no immediate resolution limits and it has no immediate size limits on the size of the masks. These advantages mean that it can be used to make extraordinarily large high resolution masks for all kinds of technologies that are not practical today including large high resolution displays, wafer scale chips, high resolution cameras, large memories, contoured / curved chips (e.g. for wrap around virtual reality helmets), folded (fractal) chips (a wafer can have regular creases to increase the surface area of the chip - however, the crystalline properties cannot be folded in such a way and work around solutions have to be achieved to make use of this property) and many different kinds of monolithic chips and chip level sub assemblies. Fractal Sensor Technology The robotic cubes themselves can be made from extruded parts but their internal sensors to detect internal position and movement have also to be designed to be nano technology compatible. We can't use optical sensors, or clever mechanical arrangement - instead we need a sensor which can be scaled from large to small where small usually means below 0.1 microns. Such a sensor technology is a 'proximity's ensor.

There are two types - capacitance and inductive. A capacitance sensor works by detecting changes in the amount of charging current of an open ended capacitor which changes with changes of its immediate surrounding environment. An inductive sensor works by using a coil to detect the immediate metallic surrounding of the coil by detecting changes in the frequency of an oscillator. Magnetic properties of the coil are altered leading to detection of the passing metallic object. The sensors are illustrated below: - Capacitance sensors are also good for detecting non metallic objects as capacitance is affected by dielectric materials which include plastics. As objects scale to the nano world, the shape of the inductive and capacitance sensors resemble more of a loop or wire or a flat plate rather than their normal equivalent in the macro world.

Micro Engineering Revolution Because now virtually everything at the smaller scales is accessible through using shape changing robots, there will be a revolution in micro engineering To some extent we need to ask whether we need to go down to the nano technology area to make for example a shape changing robot type material. We can do that now with what is documented here! In any case, molecular level control would be virtually impossible. Even if it were possible, self repair would be needed and communication to and from the larger scales as implemented by the electrical contacts on the robotic cubes will be needed - but once again all that is available now!

So why go down to nano technology scales? The only good remaining reason it to make exotic chemicals cheaply - there are no other good reason any more! The thunder of nano technology has been stolen by shape changing robots - forever! Self Miniaturisation As stated earlier, shape changing robot parts can be etched using standard photolithography equipment and improved upon by higher resolution lithography equipment. Even that can be exceeded by the above photo mask & molecular beam manufacturing technique.

We also stated that shape changing robots can make themselves and we could miniaturised these factories quite easily by getting the shape changing robots to do the hard work. There have been lots of talk about making such equipment but no one has figured out how to implement the technology. With shape changing robots its simply a matter of feeding it with new lower sizes for the self replicating factories and to switch to different production technologies as it goes down the scale. Its perfectly feasible to achieve self miniaturisation now that we have a formal method with real engineering to see it all through. Sub Micron Shape Changing Robots & Molecular Engineering With the development of micron sized robotic systems that can create their own photo masks for molecular beam etching, the possibility exists for mass producing photo masks using these shape changing robots with geometry that are finer than 100 nm without having to resort to x-rays and other exotic photolithography methods.

The computer chips can then be miniaturised as well. But more importantly, the kind of mechanical robots that are built at that scale are capable of making inroads into molecular engineering. Diagram below illustrates the concepts. The Universal Assembler We will be able to create micro miniature tubes a few hundred nano metres wide using shape changing robots. We can then pass fluids through them while a series of chemically coated surfaces and / or buckets that contain very tiny quantities of potent reactive chemicals which are accurately positioned at calculated intervals to give the highest possible reaction rates. The buckets either have narrow holes to let out their chemicals or are gated allowing molecules to leak at a fixed and controlled rate.

The difference here with standard chemistry is that the reactants and products are not given time to reverse their chemical action because the channels are narrow and the fluid filling it is constantly on the move. Enzymes typically process millions to billions of molecules per second and this technology would increase the efficiency of the enzyme several fold over conventional techniques because the reactants and products do not build up for the reaction to slow down. Where non replenishing reactions are used, the shape changing robots can remove the spent coated plates and buckets to rejuvenate and sustain the production system. The kind of molecules that can be synthesised can be much more complex because we can use direct chemical synthesis pathways that otherwise might result in intermediates that react with reactants or products in unexpected ways. Also we have total digital control of a programmable molecular assembly system!

We can also sense out required molecules by gating them into chambers where their signatures can be established to identify that the correct substance has been manufactured. The typical system that could be built using this technology is described in Mechatronics Universal Assembler. To see what other kinds of things can be done with this technology refer to the Silicon Muscle Project for an example of its application. Problems With Today's Research Ideas & Funding Compare all this with ideas of molecular manufacturing based around STEM probes as robot arms to perform molecular assembly which fumbles into nonsense when energy considerations for molecular manufacturing are taken into account. (The titled "Problems With Current Nano Technology Research Ideas" goes into some depth on the matter.) Direct Assembly vs. Robot Arms Using straight line assembly method like this, it should be possible to synthesise for example continuous fibres that are single molecules that are several metres long possibly organometallic compounds with extraordinary properties such as strength and electrical conduction at a very cheap price.

These materials may even be used by the shape changing robots themselves to make memory storage devices and other kinds large macro-molecular devices because these molecules are large and can be handled by the shape changing robots. Miniaturizing the robotic cubes allows the shape changing robots to handle smaller molecules but unfortunately, when they get below certain sizes, their physical component size becomes comparable to the individual atoms and molecules which means they won't be able to function properly. Furthermore, it would not be possible to shrink the micro controller in the robotic cube any further before quantum effects and structural integrity problems overcome the circuit performance. Those kinds of problems can be left to another generation of scientists and engineers to solve but the possibilities of making molecular production plants is almost a reality and we don't need any billion dollar chemistry research programs to get there - unlike current nano technology research! The Future of Nano Technology & Biotechnology Shape changing robots will wipe out most conventional research into biochemistry. Miniaturised chemical factories for DNA synthesis is one of the prime candidates for automation using this technology.

One of the goals of nano technology as researched today is to deliver a system for making DNA of all descriptions to order so that proteins and other chemicals can be built on top of that process. We can make DNA to order at the larger scale but the task is very daunting because of the slowness of the reactions involved and the thousands to millions of molecules needed to make a useable strand of DNA. Using shape changing robots, this task can be speeded up enormously with millions of micro tubules which add one DNA base pair at a time in an absolute controlled environment where the end product gets filed away in numbered chambers which can then be brought together with other DNA segments synthesised and stored in other chambers to make larger DNA strands. We could be looking at an hour or so to make a million base pair DNA strand giving scientists the opportunity to synthesise a vast range of DNA fragments to order giving them the opportunity to make chemicals in much the same way as computer programmers writing computer programs. Since there is very little chemistry involved in making the laboratory the time scales to manufacturing these miniature laboratories is only a few years unlike the decades and billions of dollars needed by nano technology research as practised today to deliver the same technology by synthesis of the entire laboratory with thousands of different chemicals that all have to co-exit together. Self Experimenting Systems We all make mistakes when writing computer programs and so it is with synthesising chemicals to order.

Sometimes, the expected result is wrong and we have to build several hundred variations on the same theme to check out which chemical has the best affinity for the task in hand. This can take months to years but now we are saying it need only take a week or so. Much of the process of synthesising different chemicals can be automated into the tiny labs and even the experiments to check the activity of the resulting products can be checked under automation. Even the task of varying the synthesis can be automated to find chemicals with the best affinity. This concept of goal directed optimisation work can be undertaken with the minimum of supervision and waste.

We should however be careful of emergent behaviour in these systems. The Future Possibilities The natural question to follow up with is to ask whether chemical factories can ever compete with biological organisms in making complex molecules as currently deliverable with biotechnology today. The answer is very grey and probably lies in three parts. The first part is making a suitable organism that makes the desired chemical - that is, some chemical we may want to make are toxic or not amenable to biotechnology manufacture. The second is speed of manufacture - biological organisms are fast needing around 20 minutes to reproduce and not all of that speed could be easily duplicated using a shape changing robot chemical factory. If we were to make enzyme arrays then the task could be speeded up but to make enzyme arrays you need to do an awful lot of research!

The third part is bio hazard - that is the organisms we are making are genetically re-engineered and could be deadly if it escaped into the environment. Very little of that danger exists with shape changing robots since they require a source of electricity and a computer program to make its hardware work. What if you could turn air into diamonds? What if you could fix all the damaged cells in your body and eliminate any infections or cancers?

What if you could create almost anything you wanted out of sunlight and garbage? Nanotechnology promises to do all that in the future, but like almost any technology that can bring great benefits, it can also bring great dangers. Nanotechnology is machines built on a scale of nanometers. Just as a millimeter is 1/1000 of a meter (your thumbnail might be 10 to 20 millimeters across), a nanometer is 1/1,000,000,000 of a meter (about 5 to 10 atoms long). This means that nanotechnology would be built up atom-by-atom, which is not the way humans build things now, but is similar to the way that Nature builds. All living things come from strings of atoms, protein molecules, that make copies of themselves.

Assembling atoms is how trees, humans, and other forms of life are born, grow, and live. Nature builds from the atoms up. Since human hands are too big to handle atoms, we build down from giant chunks of atoms. From an atom's perspective, a pencil is a giant chunk of atoms, and putting it in a pencil sharpener is a very clumsy way to remove lots of those atoms. The wood in the pencil was built up from atoms by a tree. Humans cut the tree down and then built down to the pencil by breaking away many of the atoms.

Since humans first started making things, we have developed finer and finer control. Smashing stones together made the first stone tools millions of years ago. Advanced technology makes today's computers with tiny electronic switches just a micrometer (1/1,000,000 of a meter) across. Even that advanced technology builds down from big crystals of silicon instead of up. Scientists and engineers started thinking about how to get the kind of control that Nature has. They are trying many different approaches and it may not be long before one of them, or a combination of a few of them, works.

Nanotechnology works by manipulating matter on the atomic level. It builds machines up by placing atoms precisely instead of building down by breaking away lots of atoms from a big chunk of them. Nobody knows exactly how it will be built because nobody has yet come up with a practical method to build nanotechnology. When it can be built practically, however, there are plans for how to build more.

Tiny nanotechnology robots, or nanobots, will be able to move around, sense their environment, and handle atoms. They could be programmed to make more nanobots, which could also make more nanobots. Their energy could come from many sources, including light. In some ways, they would appear to be alive, eating sunlight, handling atoms, and making children nanobots, if that is what they were programmed to do.

Technology is used to make technology, like breaking stones to make a stone knife, which you can use to make a spear or carve other tools. Nanotechnology could be used to make more nanotechnology. If a nanobot is created that can make another nanobot in one day, then on the second day each one could make another, so there would be four. On the third day, the four nanobots would each make another, so there would be eight.

In one month, there would be 1,073,741,800 nanobots. The number of nanobots doubling everyday is a guess, but doubling is the kind of growth that we see in the history of technology. The power of a computer that you can buy for $1000 doubles every two years. For a long time, the accuracy of clocks doubled every 30 years (the first mechanical clocks "lost" 15 minutes everyday). If doubling does occur, then nanotechnology will be everywhere soon after someone can finally make it somewhere. Nanotechnology may change us in many ways.

First, it could change us physically. If nanobots patrolled our blood streams, looking for invaders (just like our white blood cells already do), we might be able to program them to protect us against any infection. If nanobots fixed cells that developed cancer or simply became old, we might be able to live as long as we want. Larger changes could come in how we would live.

Imagine a world in which almost any design could be turned into the real thing. Instead of downloading music from Napster, you could download the design for an airplane and have your nanobots build it for you. That would change how we work and how we play. If you did not have to worry about food and shelter, would you sit around all day playing video games, or would you search out the secrets of the Universe? Engineers and scientists change nanotechnology by figuring out how to build it in the first place, and then how to improve it.

Teachers will educate on how to use it. Architects and artists will imagine and create the designs of what it will create. Politicians and activists will debate how it should be used. Everyone will decide how he or she will use it. Everyone may also have to decide what dangers it may bring. There may be many roles for people to play that are hard for us to imagine now.

Ten years ago, nobody would have thought of students creating a website for their school, but that is a role that allows young people to have an impact. Nanobots could, in theory, recognize any kind of atoms and then assemble them into any kind of structure. That means that they could make anything for which their programs have a design. That is how nanobots may be able to grab carbon atoms out of the air (humans exhale carbon dioxide and cars exhaust carbon monoxide) and then build with those carbon atoms.

Diamonds are just carbon atoms arranged into a crystal structure, which is a very simple design. Complex designs for incredibly tall buildings that reach up to satellites, personal airplanes, toxic waste recycling factories, or a "Holo deck" (from Star Trek) will allow nanobots to create those things, too. Nanobots could create food by mixing water with the carbon they pull out of the air. We would use nanotechnology to create nearly anything we could design. This could be done to save people from starving to death, or to conquer another country.

Even something simple like fire has both costs and benefits. It sometimes burns down houses and kills people, but it also keeps us warm and cooks our food. Nanotechnology is much more powerful than fire, so it will have bigger costs and bigger benefits. Many people in the world do not have enough food and starve to death every year. Many also die of diseases. Nanotechnology may be able to create nearly unlimited amounts of food and cure almost any disease known.

That same power could create weapons by people who want to use them to attack others and by people just trying to defend themselves. An accident could happen and nanotechnology could start causing harm that nobody intended. Like any technology, nanotechnology needs to be evaluated. We can decide what the costs and benefits are and how likely each may be. If we can build nanotechnology so that it saves many lives and has only a small chance of hurting anyone, then we will probably evaluate it as "good" and continue to develop it. If the chances of it destroying all life are too high, then we will probably evaluate it as "bad" and stop developing it.

There are two problems with this, though. First, it is very hard to predict the impact of a technology. The inventor of the laser had no idea that it would eventually be used in CD players and in eye surgery. Second, even if most of us decide that a technology is too dangerous, there are many people who may not agree or might just keep on developing it anyway. Even though there are problems, the best path is for as many people as possible to understand powerful new technologies so that they can be involved in evaluating it.

Otherwise, someone else will make the decisions and we may not like the results..