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Will nanotechnologies cause danger to people?

In August 2003 information appeared on creating molecule-powered engine which is billion times smaller in size than the ordinary engine of our vehicles.
The tests for this engine were successful. Scientific journals wrote that this is an important point in the development of nanotechnologies. Microscopic engine can drive microscopic vehicles. It is known that proteins in our body work as engines as well. This fact inspires nanotechnologists. This means that human’s body has hidden reserves. It can clear up blood vessels, repair damaged cells and change the structure of the tissue, both natural and artificial.
Nanotechnologists’ work is difficult – they deal with the size 80 times smaller than hair! Only such size can compose molecule constructions.
Jenny Vong, Doctor of Science, recently described this in the Nature magazine. She, her scientific adviser Professor David Lei along with chemists from Bolonia designed and built molecule rotor engine. Such “engines” are common in natural conditions (for example, they drive tiny eye muscles which allow us to read), but it is hard to produce this engine artificially. Even physics for producing it is different – quantum physics! On this level thermal energy makes molecules and their components to “dance”, that is move chaotically. One has to control this movement to create molecular-driven machines. How could the scholars achieve this?

The research team relied on hydrogen ties which compose the molecule of water. This intelligent natural tie provided the capacity to attach two rings to the loops having 1/millionth of millimeter in size. Small rings move throughout the bigger ring after receiving light with different length of its waves, that is they receive the fuel for the chemical reactions destroying hydrogen ties. Every small ring blocks the movement of another ring, therefore they both move in the same direction. This gives us rotor engine driven with light.

Earlier microscopic rotors were produced as well, but the molecule composed of the rings blocking each other can rotate only in one direction and not to move chaotically as it was in other tests. The movement driven by warmth and chemical reactions can be both circular and rectilinear – back and forth. Professor Lei is convinced that molecular engines are perspective and the tiny rotor engine they were able to produce demonstrates how such engines can operate. Where can they be used?

It is hard to answer this question yet. Maybe this will be some “turned on” surfaces made of materials reacting to outer irritants and changing their attributes. Or some sort of winch using molecular (polymer) chains, which allows to change the length and shape of such chains and create any materials the person needs. Thinking in more practical terms, it is possible to produce socks protecting against bacteria. However, all this are issues for tomorrow. First we have to find out how adjust such machines to the surrounding world. And this raises some concerns.
As many scholars conducting scientific research, Professor Lei makes fun of the concerns connected with the molecular technologies. However, scare us with them. According to one well-known fantastic scenario, myriads of so called “nanobots” will lose out of people’s control and will reduce to dust everything they will encounter. This is described in book “Prey” by Michael Krichton. Will our world become the prey of new technologies and their creatures – nanobots who got mad? This fantastic scenario scared even British Prince Charles. What are nanobots?
This term is used for microscopic robots. Such robots will be able to conduct microscopic surgeries inside human body, heal wounds, destroy inflammation and parasites and so on. In a word, they will extend the duration of people’s lives. Nevertheless, they are only robots, and if their operating program fails, they will quickly destroy the body of the person. Imagine, if after such a failure nanobots able to self-producing will start produce themselves and eat everything around. This will be the end of the world, “gray mucus” will fill the world. This terrible scenario terrified Prince Charles so much that the monarch asked experts for consultation – whether such things are possible or not.
One of the experts, Roger Hifield believes that there is no reason for concerns. Before coming to this conclusion he asked specialist on designing space equipment, Doctor of Imperial College in London Tom Pike to research the issue of nanotechnologies.
Doctor Pike explained that the idea of “gray mucus” aroused in 1986 when book “Machines for Creation” by Eric Dreksler was published. Three years ago one of the founders of Sun Microsystems company Bill Joy made a remark that because of such “gray mucus” we can cease to exist, and this can happen because of making only one mistake during a laboratory test.
The idea of “unpredictable risks” caused by nanotechnologies was discussed in 2003 by the initiative of Canadian group “Etc.” This and other debates raised concerns in Prince Charles. Are they justified?

Atoms have size of 0.1 – 0.3 nanometers (nanometer is 1/ 10 billionth of meter). For example, 200,000,000,000,000,000 can accommodate inside the dot we put at the end of this sentence. Constructing nanobot is similar composing robot from the parts of constructor Lego for children. However, atoms are round in shape and look like beads, therefore the surface of a nanobot will not be smooth and will resemble the cell for eggs we see in stores. Tom Pike explains what we need for conducting such work and explains that such work is so complicated that it is early to say about possible dangers.
First, there will be the need of “assembler” – certain device able to select atoms and compose them in such a way that they would be able to replicate themselves, producing new nanobots. In addition, there is the need of tiny engine like microscopic eyelashes which bacteria use to move. We need “brain” as well – some models of electronic charge using polymers as conductors and able to transmit the orders for replicating themselves.
However, it would be wrong to think that nanobot is just a small copy of the clumsy robot which have already been created. First, atoms are not parts of a constructor for children. Atoms attach to one another by different ways. When the temperature is usual, they also “jump”. “Fog” of electrons around an atom can change the shape and attributes of electronic “clouds” around neighboring atoms, so that the adhesive ability of the “bricks” of our construction will be changed independently on our will. In addition, “Geizenberg’s principle of uncertainty” has to be taken into account as well. According to this principle, the location and principle of an object cannot be defined exactly (the German physicist discovered this principle in 1927). Summing it all up, is it possible to operate atoms when their components are so hard to fix?
It is possible. Doctor Pike operates them in his laboratory with the thin needle of the device called atomic microscope. This big primitive collector of atoms should be frozen below 0 degrees Celsius to stop chaotic movement of atoms. It is a very slow process to create something by means of them. It took the team from IBM 22 hours of work without stopping to write the company logo with 35 atoms of xenon.
Another problem is how to make nanobot select the atoms necessary for construction of the creature similar to it. Doctor Pike makes this with the help of flashes of light and analysis how the light is absorbed – in this way the necessary atom can be singled out. There is another approach – researching the atom attached to the end of the microscope’s needle. However, constructing the atomic creature is a heroic deed because one has to select about 10 million atoms to compose it.
There is one more problem. From time to time biological systems make mistakes (so called mutation). Mechanic robots stop functioning. “Anyway, you will have to deal with entropy (natural tendency of any (natural attribute of any non-regulated substance”, Doctor Pike says. It will take billions of atoms to create a self-replicated nanobot. Meanwhile, the final product will not meet the target exactly, this thing will be bigger in size than nanobot. In fact, there are creatures having such a size in nature – these are bacteria. The creature having about 1,000 nanometers in size is called microbot, viruses are smaller, their size is 20-100 nanometers, but in addition they need living cells to breed.
However, even after 4.5 billion year period when life has been existing on the Earth the nature did not produce self-replicating nanobots. Meanwhile existing microbots are too meticulous about their food. Some of them eat tissue, others can eat even wet stone. Many eat our food in our stomachs. But no microbot is able to eat the whole world. “Nanobots are still the objects of phantasy books”, Doctor Pike says.

In real life, nanotechnologies are used for producing new medicine, new solid construction materials, clothes which cannot have stains, produce computer displays and more high-speed radios, not nanobots-killers. Prince Charles was concerned in vain…