 | This article is rated C-class on Wikipedia's content assessment scale. It is of interest to the following WikiProjects: | ||||||||||||||||||||
| |||||||||||||||||||||
.jpg){kind=small}
Potential edit
Could something from this article be integrated in the wikipedia article?:
"Nanotechnology and the arrival of the Diamond Age By Henry Kluytmans.
An enormous revolution is arriving.
People who dislike technical en social changes will not be pleased by the developments that are likely to take place in the near future. A great revolution is bound to arrive. A revolution more radical than the industrial revolution, that will probably occur within several decenia. If so, most people alive now will be witnessing its arrival.
We consider the time before the industrial revolution a barbaric period in human history. The average life expectancy in medieval times was a mere 30 years, there were no anesthetics, many people had to do backbreaking physical work and made considerable more workinghours than presently common. The mental freedom was very limited because of supervision by ecclesiastical authorities.
However after this new revolution people will also consider the present time as a barbaric period in human history. As a period where people still suffered from physical diseases, material poverty, monotonous soul-killing work, economical dependence and social/cultural limitations.
This new revolution will arise through the appliance of a fundamentally new technology called Molecular Nanotechnology (MNT). This technology, which currently has only been theoretically applied, will replace almost ALL conventional production methods because it can produce things many times cheaper and better.
The consequences of this new technology cannot be compared with the predicted consequences of applications like the computer or the internet. For example, the paperless office, predicted for many years, has still not arrived. This is mainly because current computer screens are not a fit output device for reading large amounts of text for prolonged periods of time. When the contrast of the output device will approach that of printed paper, when the illumination will be passive, and when it can be moved just as conveniently as conventional paper, then indeed, the paper production of offices will decrease drastically. Also the current fuss about the consequences of a general use of the internet are in my opinion heavily exaggerated. This probably has some commercial causes. Of course there will be social implications, but they will be no greater than those induced by the introduction of the television or the telephone.
Nanotechnology however is an application that will intervene at a much more fundamental level, comparable with the discovery of fire or the invention of the steam engine.
What is Molecular Nanotechnology
It means fabricating things with molecular precision, i.e. the building of objects (including houses, food, cars and spaceships) using individual atoms and molecules as buildingblocks. The typical dimension of the smallest buildingblock is 0.2 nanometers. This is the dimension of a typical atom (carbon).
Molecular Nanotechnology should not be confused with conventional chemical bulk production methods, presently being used to produce chips. Although here too, the dimensions are measured in nanometers (the smallest resolution achievable with current lithographic technology is about 300 nanometers). However with lithographics there is no way to determine the position each separate atom will take. Only a statistical probability can be estimated. Molecular Nanotechnology is not just miniaturization pushed to it's limits, it is a totally new method arranging matter to create products.
The most common view of the ultimate molecular production method is the use of microscopic fully automatic assembly robots being used universally to create objects out of molecular building blocks. These nano-robots will be smaller than a human cell, probably having dimensions in between that of a virus and a bacterium, and are usually referred to as assemblers.
Assemblers will have one or more manipulators, which will be able to handle separate atomic and molecular buildingblocks directly. They will be controlled by a reprogrammable computer inside the assembler. To separate its internal environment from the external surroundings the robot will contain a wall. For operational simplicity the internal environment should be chemically inert (vacuum or an inert gas). This way it's possible to use very reactive molecular parts (i.e. free radicals). These are required as intermediate products, to be able to fabricate very strong materials (i.e. materials containing very strong molecular bonds).
Assemblers should be able to fabricate anything constructed from a limited selection of molecular parts. Probably parts containing following atoms : carbon, hydrogen, nitrogen, oxygen. When the assemblers themselves are constructed from exactly this same range of parts, they should in principle be able, using the right software, to even make copies of themselves, i.e. they will reproduce!
A universal assembler will be able to create almost anything possible from the available building blocks, including a copy of itself. However most products will be created by assemblers more specialized for producing only certain products. They will have a more simple construction and also be much more efficient.
The manipulators used in assemblers will have dimensions of about a 100 nanometers. Present predictions indicate that manipulators of these dimensions will, in principle, be able to execute a million operations per second. (One operation could be the placement of a molecular part.)
This can simply be calculated: The speed of movements scales linear with the dimension. A manipulator of 10^-10 meter which can handle 10^6 operations per second corresponds with a manipulator of 1 meter which requires a 100 seconds per operation! This comparison shows that a million operations per second is not an overestimate.
But even with a million molecular-part-operations per second it takes an astronomical long time to create a macroscopic object. An object consisting of a kilogram of carbon contains more than 10^25 atoms. If the placement of every atom takes only one single operation and all operations can be carried out with a frequency of 10^6 per second, then it will still take more than 10^19 seconds to build this object. This equals about 10^12 years. Longer than the estimated age of the universe! It should be clear that for fabricating macroscopic objects great numbers of parallel operations are required. Only by using many, many, many minuscule assemblers a macroscopic object can be build in a acceptable time.
Fortunately, a fast way to create these large numbers is available! Because assemblers can be designed with the capacity to reproduce and thus create exponential growth of their numbers.
One can calculate that theoretically one such a selfreproducing assembler (in this calculation estimated containing about 10^10 atoms) can create a mass of 1 Kg of copies within 50 generations (about 6 days). And in 139 generations (12 days) it could have created enough descendants to equal the mass of the earth (in 159 generations the mass of the sun!). Naturally this is not very realistic because already after a short time, there will be problems supplying the amount of materials and energy required for the production processes. Because of these constraints eventually only cubic growth is possible (in space) or on a surface (like on Earth) only square growth. However in reality there are even more constraints (for example cooling problems, etc...). But it should be clear that using selfreproduction, in principle, enormous amounts of products can be produced in very short times.
The Earths volume is aproximately 10^21 cubic meters. The Earths mass can then be aproximated by 10^24 kg (when taking 1000kg per cubic meter). Reproduction of a assembler will take 10^10 / 10^6 = 10^4 seconds (3 hours). The mass of an assembler is aproximately 10^10 x * 10^-25 = 10^-15 kg. Time required for growth to a mass equivalent to Earths is about 2 log( 10^24 / 10^-15 ) * 10^4 seconds = 10^6 sec = about 12 days. ( This calculation is only intended to illustrate the logaritmic scales of exponential development. Numbers are therefore rounded to powers of 10. Supply of energy and raw materials are not considered because of simplicity. )
Atoms, in a matter of speaking, are the LEGO™ buildingblocks of every physical object, including ourselves. And when Molecular Nanotechnology has become feasible, at last we will have hands small enough to manipulate these LEGO blocks, and to build anything block by block. When applying molecular fabrication methods, objects only need to be specified by software and can then be build by minuscule fully automatic assemblers, without any intervention of humans. However selfreproduction is an essential condition for making molecular fabrication an ecconomically feasible production method for macroscopic objects.
Selfreproduction
Selfreproduction is a technical method which we presently have mastered only in a very limited way. In Japan there are some plants where robots produce other robotic systems including copies of themselves. However the prefabricated parts being put together are relatively large. Ofcourse, the ultimate goal is a system able to reproduce itself from the raw materials available in its natural surroundings, without the input of any prefabricated parts. In general one can say, the less prefabricated parts there are, the more difficult selfreproduction will be. However completely autonomous selfreproduction is not required, the prefabricated parts for molecular machines can be created using conventional (chemical bulk) production methods.
There already are complete descriptions of autonomous selfreproducing systems. However these are virtual systems in a simple two dimensional world of cellular automata [Von Neumann].
The Earths industries in total are an example of very complex and large (mainly) artificial product that does selfreproduce. The Earths industrial production is still growing exponentially.
An indisputable prove for the possibillity of total autonomous selfreproduction at the molecular scale is the fact that the whole biology is based on it.
A consequence of building objects from separate molecular buildingblocks (or even single atoms) is that selfreproduction can be realized more easily than using conventional technologies. This is a result of the exact equivalence of the apllied (quite fundamental) building blocks. All atoms of the same type (i.e. from the same cell in the periodic system of elements) are by definition physically indistinguishable (when put in the same quantum state). Because all buildingblocks of the same type will be exactly indentical, it is not required to do any quality checks in the production process. It can be assumed that they will all be exactly according to specifications. This simplifies realizing selfreproduction considerably. One of the main problems creating autonomous selfreplication using conventional technologies has been the quality check of the parts.
Exactly the implementation of selfreproduction will make the cost of production by molecular fabrication methods many times cheaper than conventional fabrication methods.
Copying objects
When we can build things atom by atom. we could also take them apart atom by atom. If we remember the locations where every individual atom was placed, we could rebuild the original using this information. Also we could build multiple copies of the original. These will be EXACT copies! We could, for example, make a copy of a painting of Rembrandt. This copy will then by definition be indistinguishable from the original (according to present physical theories). This is almost similar to the copying of software : the original and the copy of a peace of digital information are exactly identical.
Applying molecular fabrication all materialistic objects will be reduced to information, i.e. software. Making exact copies of physical objects will be possible. We will be able to handle atoms like we now do bits.
Matter-fax
We could analyse an object by taking it apart atom by atom. The (now digital) information regarding the construction of the object could then be transferred to a different location. There the object could be rebuild atom by atom. A kind of matter-fax.
In principle we could even transfer people to other planets using this method. Only there is a problem analysing the atomic construction of a human being because he is not composed of solid parts only. Most cells consist of a liquid medium enclosed by a membrame. Floating in the medium are molecular machines dynamically interacting with eachother. The most simple way to analyse this system would be to stop all the processes first. For example by freezing the body (cryonic suspension), or even better, by vitrification (put it in stasis).
The amount of information required for describing the precise atomic construction of a human body is huge. However this information can in principle be very effectively compressed by a considerable amount. For describing the body (not including the state of mind) it should be sufficient to take only the information contained in the DNA. The amount of information required to describe the human mind can only be estimated very roughly, but could appear amazingly small.
Applications and economical implications
Because atoms can be used as buildingblocks most raw materials can be obtained directly from the environment, like plants do, from sand, water and air.
A number of products of applied molecular nanotechnology will be : materials 50 times stronger and weighing less than the strongest conventional materials, almost complete immortality of the human body, selfrepairing machines and materials, selfreproducing machines, mechanical computers smaller than a human cell, and much much more...
Some quotes (by K. Eric Drexler):
"A short summary of what molecular nanotechnology will mean is thorough and inexpensive control of the structure of matter. Pollution, physical disease, and material poverty all stem from poor control of the structure of matter. Strip mines, clear-cutting, refineries, paper mills, and oil wells are some of the crude twentieth-century technologies that will be replaced. Dental drills and toxic chemotherapies are others." Drexler in "Unbounding the Future"
"Nanomachines, with their broad ability to rearrange atoms, will be able to recycle almost anything. Using nothing but sunlight and common materials, and with no by-products other than waste heat, they will produce a wide range of products. With production costs similar to those of plants, they will enable the clean, rapid production of an abundance of material goods. The benefits could be especially dramatic for the third world." Drexler in "Machines of Inner Space"
"Potential medical applications also show that small systems can have big effects. Cells and tissues in the human body are built and maintained by molecular machinery, but sometimes that machinery proves inadequate: viruses multiply, cancer cells spread, or systems age or deteriorate. As one might expect, new molecular machines and computers of subcellular size could support the body's own mechanisms. Devices containing nanocomputers interfaced to molecular sensors and effectors could serve as an augmented autoimmune system, searching out and destroying viruses and cancer cells. " Drexler about medical MNT applications:
Consequences of the availability of personal production facilities (e.g. anything-box) are large. The present economies are largely based on the scarcity of (materialistic) products. This kind of economy will therefore quite likely disappear almost completely.
.... ....
Present state of molecular nanotechnology
At this moment we can already move separate atoms by pushing them around on a surface using a so-called Scanning Probe Microscope. However we are not yet able to build three dimensional stable constructions from molecules or atoms.
A Scanning Probe Microscope (SPM) is a kind of pick-up needle having a tip of atomic dimensions which can be moved above a surface at very minute heights to detect very small (atomic) differences in height levels. The tip of the microscope is moved using piezzo electric crystals. These crystals contract and expand in certain directions influenced by artificially induced electric fields. By varying the voltage levels, displacements of only hundreds of a nanometer can be realized. These displacements are even smaller than the dimension of a single atom!
The (height) distance of the tip to the surface can be measured using different methods. A Scanning Tunneling Microscope measures the current which can jump to the surface (via the quantum tunneling effect), this current will vary exponentially in proportion to the distance. An other method measures the force the surface is executing upon the tip and will try to keep it constant (Atomic Force Microscope). Using this kind of scanning microscopes surface details having dimensions of atoms can be made visible.
As soon as method for attaching a chemical reactive workpeace to the tip of a SPM has been developed, which can handle molecular parts selectively, we can finally pick up and place molecules instead of only shifting them around. Then we can really start building and testing artificial (i.e. non-biological) molecular machines. Blueprints for different parts of such molecular machines have already been designed. The next step will be, assembling these machines into a functioning assembler.
The development of a chemical reactive gripper to handle and manipulate molecular workpeaces presently seems to be the most important next step. In my personal opinion I suspect the development to accelerate considerably after this difficult step has been realized.
Utopia or reality?
For people unfamiliar with the concept, the products of MNT and therefore MNT itself, seem like science fiction. There is no doubt the concept of space travel must have sounded equally strange around 1870 when even planes and automobiles did not yet exist. Molecular Nanotechnology is not contradictory with the present laws of physical science, but it does challenge the capabilities for imagining the enormous technical possibilities still within these constraints?
The predicted possibilities en conseqences of MNT are absolutely inconceivable, and understandably this induces skeptical reservedness. Slowly but surely more and more skepticism disappears because the supporting technical explanations based upon established technical, chemical and mathematical knowledge keeps growing. MNT is presently still theoretical, like space travel was theoretical until the Sputnik circled the Earth.
"Every sufficiently advanced technology will resemble magic." Arthur C. Clarke.
For people two centuries ago television would have been magic.
Maybe the descriptions of a world with many applications rendered by MNT will resemble utopia for most people living now. But for the people of the future used to living with it (or even for the present people after a period of adaptation) it will all be ordinary. The present western world where almost everybody possesses a car, television, a house with central heating, a shower, refrigerator, telephone, etc. would have resembled utopia to the people living a few centuries ago. However most people living today owning these products will not dwell on this fact. They are busy pondering about other things, like : their children, their jobs, vacation time, their leisure occupations etc... Regarding human aspects, living in a world with applied MNT, will not differ very much from our current world.
Biology
For those who still doubt the technical feasibility of MNT, biology is an excellent proven example of MNT in practice. A cell is no more than a membrane encompassing a liquid containing a large number of floating nanomachines all having specialized functions.
The ribosome resembles a simple nanomanipulator, even capable of reproducing itself. This manipulator reads the information describing a product from a kind of tape (the DNA), while assembling the product by successively grabbing certain buildingblocks (an amino-acid identified by a certain RNA triplet) and sticking them together forming a chain of coupled amino-acids. After curling and rolling itself up (what happens automatically) the final product will have formed (a protein).
Amazingly many chemical reactions taking place in biology are being accomplished by a kind of mechano synthesis. Not only are certain reagents brought into contact in a controlled and forced way using mechanical manipulations, but also mechanical force is being used to induce a reaction. Using this same principle artificial assemblers will bond molecular parts.
Social implications and dangers:
- collapse of most conventional economical systems
- social instability
- potential use as weapon (or for arms production)
My personal sugestion : Move yourself to space as soon as possible after the availabillity of applied molecular nanotechnology, and wait there untill the society on Earth has stabilized.
The diamond age
MNT having arrived, diamond and diamondlike materials (also refferred to as diamondoid, are materials consisting mostly of carbon atoms, containing small quantities of other atoms like hydrogen, oxygen and nitrogen) will grow to become the most used construction materials because of their excelent qualities in multiple areas (strength, hardness, electrical conductivity, heat conductivity, etc...) Using a kind of diamond fibers, materials can be created which are almost unbreakable and have a strength/weight factor fifty times greater than the strongest conventional materials. Imagine decreasing the dry weight of planes and spacevehicles some fifty times. This will re-open the possibility for cheap and simple one-person airplane or even one-person spacevehicles. There have been estimates of a car weighing only 10 kilograms and a spacevehicle with a dry weight of 50 kilograms. Of course a car of such small weight will have to carry balast to avoid being blown away by a mere gust of wind. Certain periods in the history of mankind are often called after the most freqently used construction material. (like the stone age, the bronze age). A very fitting name for the period having MNT as its most widely used technology would therefore be : the diamond age." 193.217.192.224 02:15, 17 September 2007 (UTC)
Chemistry edit
It's not clear why the intro is all about hypothetical nanotechnology (and is the only bit that is) and the rest of the article is all about real chemistry, at length ... still could do with some cleanup, but the hypothetical stuff to a subsection is probably appropriate WP:NPOV weighting - David Gerard (talk) 16:00, 13 September 2015 (UTC)