Nanotechnology Myths and Reality
Many areas of human activity as well as the sciences are shrouded in myths. Nanotechnology, being one of the major areas of modern science is not an exception. Moreover, here the myths are inherent in the concept. For example, most people believe that Nanotechnology is the manipulation of individual atoms and molecules to build structures; however, this is a myth to many scientists.
There are at least two origins of scientific myths: A first origin is due to a lack of information and understanding, whereas a second origin is generated with a deliberate a purpose in mind. The myths of Nanotechnology come from and involve the second origin. In line with the second myth construction, the attention of 'those in power' attracted and constructed one of the greatest investment projects of all times called "Nanotechnology". Although, many would argue that it was not a myth of any kind but actually fraud; others would say that hyping of the language has played its beneficial role of an initiator of developing of Nanoscale Science.
In Pieces nanosculpture altered image.
Cris Orfescu, "In Pieces", 2004 - Nanosculpture (sculpture at molecular and atomic levels) created by freezing a tiny drop of colloidal graphite (graphite nanoparticles in a suspension) in Liquid Nitrogen at 196 degrees Celsius bellow zero. The structure was visualized with a scanning electron microscope. The monochromatic scan was captured in a computer, painted and manipulated digitally, and the final image was printed on canvas with archival inks specially formulated to last for a long time.
It should be noted that myths, in general, have a remarkable property of capturing the imagination of humans and our society. Once a myth start and takes hold it can take on a life of its own and demonstrating great vitality and longevity. Some myths are firmly rooted in our minds and are able to influence the perception of reality. In addition, there have been a few exciting "Nanotechnology-related" myths have been created after the original myths have been started. Some of these myths are generating at the very least unreasonable expectations, and for some and panic because of these unreasonable expectations to this day.
The myth about the Father of Nanotechnology
The statement that, "the Physics Nobelist Richard Feynman is the founder of Nanotechnology" is the most harmless of all these myths. This myth was originated in 1992 when the U.S. Senate Committee on Commerce, Science held a hearing on the topic of "New Technologies for a Sustainable World. Just then the speaker, Dr. Eric Drexler - the prophet of Nanotechnology cited the statements of the Nobel Laureate (Richard Feynman) in order to persuade the audience
Unfortunately, Feynman died in 1988 and therefore had not been able neither confirm nor deny this statement. Probably, if he had heard it, he would have laughed merrily. He was not only an outstanding physicist, but also a well-known prankster, no wonder his autobiographical book was called: 'Surely You're Joking, Mr. Feynman!' That's why his famous talk entitled "There's Plenty of Room at the Bottom" that had been given on December 29th, 1959 at the annual meeting of the American Physical Society at Caltech was greeted with such "amusement"... "It simply took everybody completely by surprise," as Paul Shlichta an audience member said later.
But the words: "The principles of physics, as far as I can see, do not speak against the possibility of maneuvering things atom by atom. It is not an attempt to violate any laws; it is something, in principle, that can be done; but in practice, it has not been done because we are too big" have been spoken, that is a fact.
After a quarter of a century some of the Feynman's ideas have been creatively developed by Eric Drexler; to whom we owe the appearance of the main myth of nanotechnology. Here we will often come back to the famous speech of Richard Feynman in order to remind the reader of the concept introduced by this great scientist, and also to give you a chance to enjoy the clarity and imagery of his words.
The myth about the non-waste technology
Without any doubt, we use a non wasting technology when generating an object directly atom by atom. The author uses the phrase "Without any doubt" because when people, especially officials, are looking at the pictures illustrating an atom manipulation procedure, they do not see or imagine smoking chimneys or industrial effluents. People usually consider nanotechnology as something pretty clean and sustainable that is much cleaner than usual chemical engineering.
Sunflower Fragments nanosculpture altered image.Cris Orfescu, "Sunflower Fragments", 2006 - Nanosculpture created by casting a polymer on glass. After the film was peeled-off, it was immersed in Liquid Nitrogen. The structure was coated with Gold and visualized with a scanning electron microscope. The monochromatic scan was captured in a computer and painted digitally. The final image was printed on canvas with archival inks.
If you ask a lay person who is far from Physics or Chemistry something like "How do they get the individual atoms used in the processing or building of Nanotechnology devices?" it's quite possible, that the answer will be like: "The atoms are probably stored at the warehouse, aren't they?" Sometimes, a lay preson has no clue how chemicals are used to build the products that he consumes in his everyday life. Moreover, Chemistry as a science is boring subject and is associated with environmental contamination rather then building products for consumers. Our conventional technologies ruthlessly consume various natural resources such as oil, gas, ores and minerals. In contrast, accordance with the opinion of most lay people, Nanotechnology and the uses thereof, just requires a few atoms - nothing else.
However, we have to disappoint those people who still believe in something close to this idyllic picture. The individual atoms of all known elements, except for the rare gases, are able to exist only in a vacuum. Under any other condition, other than a vacuum, the individual atoms interact with their peers forming chemical bonds. Such is the nature of things, and nothing can be done about it. Additionally, any technology requires equipment and facilities in order to proceed and yield the required process to build things, but some people do not appreciate the need of these facilities and do not appreciate the complexities and hazards of making Nanotechnology devices.
Scanning tunneling microscopes (STM) and atomic force microscopes (AFM) are powerful and precision tools for Nanotechnology development. One could say, development of these two imaging machines is visible evidence of the power of the human mind, but the use of them is also not completely safe with respect to the environment either. Let's think about it. The laboratories, engaged in the manipulation of atoms, are usually equipped with specially constructed clean rooms. Clean rooms are enclosed spaces environmentally controlled with respect to airborne particulates, temperature, humidity, vibration, noise, etc., even the operators should have at least a master degree in order to be capable of managing such a complex system.
Since many of these high-tech tools are located in large facilities, they must have a large infrastructure such as a foundation, walls and roofs, and numerous supply systems that are specialize and specific for the task at hand. Unfortunately, the construction and the maintenance of such facilities and/or labs can have a great environmental impact and need to have the proper controls and check in place to function. That's why the modern Nanotechnology facilities cannot be called completely sustainable. Maybe sometime in the future, mankind will create really environmentally friendly technologies. However, this will most likely occur when new principals are understood and exploited.
The myth about nano-machines
Some ideas of Nanotechnology started with nano-machines. Obviously and in accordance with the concept, the dimensions of a nano-manipulator that makes the nano-machine must have dimensions in the nano-scale. Let us see how this was seen by Richard Feynman first: When I make my first set of slave "hands" at one-fourth scale, I am going to make ten sets. I make ten sets of "hands," and I wire them to my original levers so they each do exactly the same thing at the same time in parallel. Now, when I am making my new devices one-quarter again as small, I let each one manufacture ten copies, so that I would have a hundred "hands" at the 1/16th size.
Tribute to Kubrick Space Odyssey 2001 - revision 1 nanosculpture. Cris Orfescu: "Tribute to Kubrick Space Odyssey 2001 - revision 1", 2006 - Nanosculpture created by freezing a tiny drop of colloidal graphite in Liquid Nitrogen at -196 deg C. The monochromatic scan has been painted digitally. The final image is printed on canvas with archival inks.
Where am I going to put the million lathes that I am going to have? Why, there is nothing to it; the volume is much less than that of even one full-scale lathe. For instance, if I made a billion little lathes, each 1/4000 of the scale of a regular lathe, there are plenty of materials and space available because in the billion little ones there is less than 2 percent of the materials in one big lathe.
It doesn't cost anything for materials, you see. So I want to build a billion tiny factories, models of each other, which are manufacturing simultaneously, drilling holes, stamping parts, and so on."
Now this approach is used in miniaturized devices which work at the micro level. The typical examples of such devises are so-called Microelectromechanical systems (MEMS). MEMS systems are widely used in the many systems in today's everyday products such as airbags in cars, in laser and inkjet printers, pressure sensors of domestic air conditioners, indicators of the fuel level in a fuel tank, pacemakers, and joystick consoles. You can see gears and shafts, cylinders and pistons, springs and valves, mirrors, and integrated circuits inside these devices and many times they can only be observed though a microscope.
However, the properties of nano-objects can substantially and many times do differ from those of larger macro- and micro-objects. For instance, if we found a way to reduce the size of transistors from 45-65 nm to 10 nm, the transistors would most likely not work properly because the electrons would be capable of tunneling through thin insulating films, while the connecting wires, which now became chains of atoms, due to the thermal motion would not be able to conduct an electric current.
We can observe the same difficulties in application of nano-objects in mechanical devises. The ratio of surface area to volume for nano-objects is much higher than this ratio for micro-objects, and the larger the surface, the greater the friction. Nano-objects can be attached to each other or to the other surfaces very easily, which is extremely harmful to any mechanical device. We would have to spend an excess amount of energy just in order to move the nano-object from place to place.
Despite the restrictions mentioned above, there are a lot of descriptions of nano-copies of various mechanical parts such as wrenches, wheels, axles, and gears in our scientific-popular literature, especially in popular media reporting. It is assumed that by utilizing these nano-scale devices, models of real nano-machines can be created. We will not discuss how the authors are going to describe how to build these nano-copies. However, it should known that sometimes physicists love to solve such problems using ab-initio calculation models and do the calculations even just for fun.
On the other hand, Nature has created so many different molecular machines over billions of years of evolution, that scientists will have to spend many years to understand, copy, and adapt these molecular machines in and into the technologies of the future.
The most famous example of a molecular motor found in nature is the bacterial flagellar motor. There are also a variety of biological machines in our body. These biological machines provide functions such as muscle contraction, the beating of our hearts, transport of nutrients, and transport of ions across a cell membrane. The efficiency of molecular machines which turn chemical energy into mechanical work often is close to 100% and consumes less than 1% of the energy resources of the cell. While the conventional electric motor is far less efficient.
It seems like the biomimetics approach (in Latin "bios" means life and "mimetis" means an imitation) is the most realistic way to create nanomechanical devices, and an areas where the communities of physicists and biologists can join together to bring tangible results.
The myth about nanorobots
Suppose we have created a digital model of a nano-device. How do you assemble it and how do you make more than one copy?
According to Feynman, we can do it by in his words, "to build a billion tiny factories, models of each other, which are manufacturing simultaneously, drilling holes, stamping parts, and so on" along with manufacture of the miniature manipulators for an assembly of the ultimate product. However, these manipulators have to be driven by man, that is to have some kind of macroscopic snap, or, at least, to act according to a software created by man. We also need something like an electron microscope (a macro-object again) to watch the process.
Underwater 1 nanosculpture. Cris Orfescu: "Underwater 1", 1998 - Nanolandscape: the artist visualized Carbon nanostructures with an electron microscope. The monochromatic scan was painted digitally. The final image was printed on canvas with archival inks.
An alternative view has been suggested in 1986 by an American engineer Eric Drexler and expressed in his futurological bestseller "Engines of Creation". The author, as all men of his generation, grew up reading science fiction. Eric Drexler proposed to use nanorobots for the manufacture of the nano-devices (100-200 nm in size). He does not mention a drilling or punching in his book; these robots were supposed to produce the product directly from the atoms. That is why these nanorobots were called the assemblers. To date Drexler theory is still theorical and the approach has remained purely mechanical; however, the science is beginning to get closer. Roughly, such nanorobot is to be comprised of several tens of thousands of parts, and every detail comprises about one hundred atoms. Throughout his book the problem of visualization of atomic and molecular items does not appear, it seemed quite natural, that nanorobots, operating with nano-objects would be able to "see" and/or identify the nano-objects, like a man sees a hammer and a nail, hammering the nail into the wall.
Drexler wrote his book about the future, about the distant future. At the time of the writing of his book, the possibility of manipulating individual atoms was not confirmed by scientists. These possibilities were not even thought of in principle, let alone the use of these principals to assemble of nano-structures. However, some of these principals have been recently demonstrated by using a tunneling microscope that successfully manipulated individual atoms
The proof of concept of manipultation of individual atoms has led to the rise of credibility to this attractive idea with regard to nano-robots. Within a few years, many government officials from around the world, journalists, and the public had come to believe that manipulation of atoms was going to be easy and achievable. The author was not an exception, despite all solid arguments in favor of non-realizability or practicality of this approach. There are a lot of arguments against this kind of approach; one of the arguments has been expressed by Richard Smalley.
"Atoms are tiny and move in a defined and circumscribed way–a chemist would say that they move so as to minimize the free energy of their local surroundings. The electronic "glue" that sticks them to one another is not local to each bond but rather is sensitive to the exact position and identity of all the atoms in the near vicinity. So when the nanomanipulator arm of our nanobot picks up an atom and goes to insert it in the desired place, it has a fundamental problem." ... "Manipulator fingers on the hypothetical self-replicating nanobot are not only to fat; they are also too sticky: the atoms of the manipulator hands will adhere to the atom that is being moved."
While Smalley, another Nobel Prize Laureate in Chemistry weighed in, Drexler's idea continued to live on. Drexler's ideas have survived to this day and are becoming more complex over time.
Presently, it has become popular to imagine millions of tiny nanobots that scurry through our body to diagnose the status of various cells and tissues, and repair damage. The nanobots are envisioned to dissect and dismantle the cancer cells, build up bone tissue by assembly of atoms, scrape cholesterol plaques off arteries by means of a nano-spatula, and break the synapses which are responsible for the unpleasant memories in our brain. But these medical nanobots could also be quite dangerous. Given that these nanobots could communicate to each other and/or to the outside world, they would be able to communicate the status of a persons organs and ultimately a person's health. This is a serious matter and public concern due to the potential possibility of the disclosure of the personal information. But more importantly, considering the rancor and the way our health system works, it is possible that this personal information could be used against that person because of the monetary costs associated in with treating that person.
Some people today really believe in this nonsense.
The most amazing thing is that almost all technologies mentioned above can be created (some have already been created). Invasive diagnostic systems that report the state of human body in situ, drugs that directly kill specific cells, systems that purify our blood vessels from atherosclerotic plaque, bioactive bone implants, erasure of memories, and even, invisible systems of remote monitoring were already being successfully used.
However, these technologies do not have nothing to do with the mechanical nanorobots in the spirit of Drexler, except for size. They have been created by joint efforts of physicists, chemists and biologists, the scientists working in the area of a synthetic science, called Nanotechnology.
The myth about the physical synthesis
May be unwittingly, Richard Feynman discloses an everlasting dream of physicists in his lecture:
"Ultimately, we can do chemical synthesis. A chemist comes to us and says, "Look, I want a molecule that has the atoms arranged thus and so; make me that molecule." The chemist does a mysterious thing when he wants to make a molecule. He sees that it has got that ring, so he mixes this and that, and he shakes it, and he fiddles around. And, at the end of a difficult process, he usually does succeed in synthesizing what he wants. By the time I get my devices working, so that we can do it by physics, he will have figured out how to synthesize absolutely anything, so that this will really be useless."
NanoHologram 3 nanosculpture altered image. Cris Orfescu: "NanoHologram 3", 2008 - Nanosculpture created by freezing a tiny drop of colloidal graphite in Liquid Nitrogen at -196 degrees Celsius. The monochromatic scan has been painted and manipulated digitally and the final image was printed on canvas with archival inks.
But it is interesting that it would be, in principle, possible (I think) for a physicist to synthesize any chemical substance that the chemist writes down. Give the orders and the physicist synthesizes it. How? Put the atoms down where the chemist says, and so you make the substance. The problems of chemistry and biology can be greatly helped if our ability to see what we are doing, and to do things on an atomic level, is ultimately developed – a development which I think cannot be avoided."
But chemists do not synthesize a molecule, they synthesize a substance of many molecules. Chemistry is a science of matter and the transformations of matter (chemical reactions). In an ordinary chemical reaction about 10 atoms near the reaction side engage in an intricate three-dimensional motion, and each of these atoms could not be set down in just the "right" place; this is impossible, even if physicists really want to do that.
There is another problem that makes the "physical" method of synthesis impossible. As has been mentioned, chemists do not synthesize a molecule, they get matter. Matter consists of a large number of molecules, for instance, 1 ml of water contains ~ 3 x 1022 molecules of water, and 1 cm3 of gold contains 6 x 1022 atoms of gold.
So, how long would it take to build a cube of atoms?
The machine of choice that is capable of moving and orienting atoms at this time is called an Atomic Force Microscope (AFM). Operation of an AFM requires a special training and a high level of education. The manipulation of atoms utilizing an AFM can be described in this way: a) take a atom, b) drag it to the desired position; c) estimate the intermediate result. The speed at which this could be done is close to the rate of laying bricks. So, generating of cube of 1 cm3 would take a very long time estimated at approximately two billion years, which is the time it took for complex multi-celled animal to evolve from a single-cell.
That is why Feynman was talking about a millions of "tiny hands", and even if millions of nanobots inside of us would not improve our health because the time of our life would not be long enough to get the results of the work that needs to be accomplished. That's why Richard Smalley tried to convince Eric Drexler not mislead the public by talking nonsense in the paper called "Engines of Creation".
So, shall we say "Rest In Peace" (RIP) to the physical method of synthesis of matter? - No, not at all.
There are at least two ways that atoms can be picked and placed and/or manipulated. First, using the same technique as described above there is a possibility of manipulating atoms by building blocks such as carbon nanotubes. By using carbon nanotubes, the problems of low weight and high reactivity of individual atoms is avoided, while the performance increases by two to three orders of magnitude.
Second, it is also possible to use the tip of a tunneling microscope to initiate a self-assembling process or activate some kind of chemical reaction(s), such as chain-growth polymerization in an organic thin film, changes of crystal structure of an inorganic substance, conformation of biopolymers, and the like. The precision scanning with a tunneling microscope of a surface with the capability of repeated exposures allows for the generation of extended objects that are characterized by a regular nanostructure.
Finally, unique samples - molecular templates such as a hexagon of metal atoms or single molecules can be obtained by this technique. Nature is able to create multiple, completely identical copies of individual molecules or whole organisms. In common parlance, it is called cloning. This process enables the propagation of entire genome or a single fragment of DNA extracted from biological material or synthesized artificially. To do this, scientists use a "molecular machines", created by nature - proteins and enzymes. Why can we not make a similar machine to clone other molecules, in addition to oligonucleotides?
The myth about Grey Goo
The extremely low performance of nanorobots has not been overlooked by Eric Drexler. In the world of "Engines of Creation", nanorobots had other problems, which for lack of space we have not been able to be discussed in detail. However, problems such as quality control, development of new products, sources of raw materials, e.g., "warehouses" for atoms, where from and how the atoms actually appear from the "stock". To solve these problems, Drexler introduced to his concept two more types of devices.
The Silkworm Larva nanosculpture altered image. Cris Orfescu: "The Silkworm Larva", 2006 - Nanosculpture created by the hydrolyzation of a tiny drop of a Silicon organometallic compound. The structure was coated with Gold in order to be properly visualized with a scanning electron microscope. The monochromatic scan has been painted and manipulated digitally. The final image was printed on canvas with archival inks.
The first type of device are parsers, antipodes of assemblers. Parsers, in particular, have to study the structure of the new object by writing its atomic structure in the memory of the "nanocomputer". This type of device would be a dream tool of a chemist! Meanwhile, despite all the advances in modern research technique, we can not "see" all the atoms, for example, in a protein. To establish the exact structure of the molecule millions of such molecules should form a crystal. Then, using the method of X-ray analysis, we can determine the exact location of the atoms in the molecule relatively to each other with the accuracy of a thousandth of a nanometer. This process is a long and a laborious procedure requiring cumbersome and expensive equipment.
The second type of devices are the creators and/or replicators. Their main task is mass production of the assemblers and their own kind. As conceived by Drexler, replicators are much more complex devices than assemblers, they must consist of hundreds of millions of atoms (still two orders of magnitude smaller than a DNA molecule) and therefore have a size of about 1,000 nanometers. If the duration of replication is measured in minutes, then multiplying in geometric progression terms allow that in one day the replicators will generate trillions of replicators, which will produce quadrillions of specialized assemblers designed to build macroscopic objects, buildings, rockets, etc.
One can easily imagine a situation where the operation of the system may switch to production for production's sake. Where an excessive accumulation of the means of production allows the nanorobots themselves grow their own population. Welcome to the revolt of the era. The revolt of nanotechnology machines! Since the assembly of nanorobots requires the system to obtain atoms only from the environment, the parsers will disassemble into atoms everything that comes under their tenacious manipulators. As a result, after some time, all the matter and what is most offensive to us, all biomass will be transformed into a crowd of nano-robots in the "gray goo", as it has been named by Eric Drexler.
Fortunately, such scenario is impossible. If, despite all of the above, you still believe in the plausibility of creation of something substantial out of atoms, consider the following two objections. First, Drexler described replicators lack the sufficient complexity to create a similar devices (their own breed). Hundreds of millions of atoms is insufficient even for a computer controlling the replication process, even for its memory not mentioning the processor and other components. If we assume the unattainable, that every atom carries one bit of information, the amount of memory is 12.5 MB which is too small. Second, the replicators will have problems with raw materials.
The elemental composition of electro-mechanical devices is fundamentally different from the composition of the environment and especially from biomass. Search, retrieval and delivery of the necessary atoms necessary elements will require huge expenditures of time and energy and will determine the actual rate of reproduction. Using a real macro world analogy this situation is similar to the one where building a machine requires search, extraction, and delivery of the materials from various planets in the solar system. The lack of vital resources puts a limit for uncontrolled spread of any population, even the one which is much more tailored and sophisticated than the mythical nanorobots.
The list of myths goes on. The myth of nanotechnology as a driving force of the economy deserves a separate article. The canonical history of nanotechnology, considering the invention of the tunneling electron microscope as the key event of this history, is a myth too. But history is written by the victors, so a global project called "Nano" determines the face (and funding) of modern science.
Rock Flowers 4 nanosculpture Cris Orfescu: "Rock Flowers 4", 2006 - Nanolandscape: the artist visualized PVC micro-flakes with an electron microscope. The monochromatic scan was painted digitally. The final image was printed on canvas with archival inks.
Myths have played a positive role. Myths have generated enthusiasm and attracted the attention of the political elite, the economic elite, and the public in the past and present. This time the attention and enthusiasm is directed to the science of Nanotechnology. However, the stage of practical realization of the Nanotechnology projects is the time to forget about these myths and to stop repeating them from article to article, from book to book.
After all, myths are also able to hinder the development of science and give the wrong direction and goals, generate confusion and fear. Finally, a new history of nanotechnology should be written - the history of a new area of science of the XXI century, the area which combines physics, chemistry and biology.
This web page is the translated and adapted English version of the Nanotechnology Myths by Heinrich Ehrlich. The original article in Russian published in the magazine Khimiya i Zhizn’ (Chemistry and Life) and republished at the Russian nanotechnology web portal Nanometer.ru is a short version of the chapter in the book Small Subjects - Big Ideas: A Broad View of Nanotechnologies. Translation by Taisiya Skorina. We are thankful to Cris Orfescu for his permission for republishing images from the Nanoart Images Gallery.
Related articles on the Internet:
- There’s Plenty of Room at the Bottom
- Of Chemistry, Love and Nanobots by Richard Smalley
- Molecular Fabrication by Eric Drexler
- The Drexler-Smalley Debate on Nanotechnology
- Drexler-Smalley Debate on Molecular Nanotechnology
- Nanotechnology Myths and Reality: A Materials Prospective presentation by E. Reynaud
- The Nanotechnology Myth
- Seven Big Myths About Nanotechnology Manufacturing