Engines of Creation or Grey Goo?

Nanotechnology is slowly creeping into popular culture, but not in a way that most scientists will like. Scientists expect that nanotechnology will lead to tiny robotic submarines navigating our bloodstream, and ubiquitous images like that are frequently used to illustrate stories about nanotechnology in the press. Yet today's products of nanotechnology are much more mundane − stain-resistant trousers, better sun creams and tennis rackets reinforced with carbon nanotubes. There is an almost surreal gap between what the technology is believed to promise and what it actually delivers.

   The reason for this disparity is that most definitions of nanotechnology are impossibly broad. They assume that any branch of technology that results from our ability to control and manipulate matter on length scales of 1-100 nm can be counted as nanotechnology. However, many successes that are attributed to nanotechnology are merely the result of years of research into conventional fields like materials or colloid science. It is therefore helpful to break up the definition of nanotechnology a little.

  What we could call "incremental nanotechnology" involves improving the properties of many materials by controlling their nano-scale structure. These are the sorts of commercially available products that are said to be based on nanotechnology. However, they do not really represent a decisive break from the past.

In "evolutionary nanotechnology" we move beyond simple materials that have been redesigned at the nano-scale to actual nano-scale devices that can, for example, sense the environment, process information or convert energy from one form to another. Taken together, incremental and evolutionary nanotechnology are driving the current excitement in industry and academia for all things nano-scale.

But where does this leave the original vision of nanotechnology as articulated by Eric Drexler? Back in 1986 Drexler published an influential book called Engines of Creation: The Coming Era of Nanotechnology, in which he imagined sophisticated nano-scale machines that could operate with atomic precision. We might call this goal "radical nanotechnology". Drexler envisaged a particular way of achieving radical nanotechnology, which involved using hard materials like diamond to fabricate complex nano-scale structures by moving reactive molecular fragments into position. His approach was essentially mechanical, whereby tiny cogs, gears and bearings are integrated to make tiny robot factories, probes and vehicles.

  Drexler's most compelling argument that radical nanotechnology must be possible is that cell biology gives us endless examples of sophisticated nano-scale machines. Drexler argued that if biology works as well as it does, researchers ought to be able to do much better. Surely we can create what are, in effect, synthetic life forms that can reproduce and adapt to the environment and overcome "normal" life in the competition for resources.

  Drexler's book raised one big spectre. By engineering a synthetic life form that could create runaway self-replicating machines, we might eventually render all normal life extinct. This scary possibility was dubbed by Drexler as the "grey goo" scenario. It is what triggered much of the public's doubts about nanotechnology. It is nevertheless worth examining the shortcomings of Drexler's original vision because this may give clues as to how we might make radical nanotechnology feasible. Designs that function well in our macroscopic world will work less and less well as they shrink in size.

  Scientists almost always greatly overestimate how much can be done over a 10 year period, but underestimate what can be done in 50 years. Which design philosophy of radical nanotechnology will prevail − Drexler's original "diamondoid" visions or something closer to the marvellous contrivances of cell biology?

 

2 . Read the text and discuss the following statements:

a) Scientists are looking for the ways to use nano-materials for ultra-powerful

computers.

b) Nanotubes have 100 times the tensile strength of steel.

c) Nano-materials are supposed to be vastly used in space.

Nanotechnology in Space

  Nanotechnology could lead to radical improvements for space exploration.      When it comes to taking the next "giant leap" in space exploration, scientists are thinking small – really small. In laboratories around the world, governments are supporting the burgeoning science of nanotechnology. The basic idea is to learn to deal with matter at the atomic scale – to be able to control individual atoms and molecules well enough to design molecule-size machines, advanced electronics and "smart" materials.

Nanotechnology could lead to robots you can hold on your fingertip, self-healing

spacesuits, space elevators and other fantastic devices. Some of these things may take

more than 20 years to fully develop, others are taking shape in the laboratory today.

Nanotechnology could provide the very high-strength, low-weight fibers that would

be needed to build the cable of a space elevator. Simply making things smaller has its

advantages. Imagine, for example, if the Mars rovers Spirit and Opportunity could havebeen made as small as a beetle, and could scurry over rocks and gravel as a beetle can, sampling minerals and searching for clues to the history of water on Mars. Hundreds or thousands of these diminutive robots could have been sent in the same capsules that carried the two desk-size rovers, enabling scientists to explore much more of the planet's surface – and increasing the odds of stumbling across a fossilized Martian bacteria!

But nanotech is about more than just shrinking things. When scientists can deliberately order and structure matter at the molecular level, amazing new properties sometimes emerge. An excellent example is that darling of the nanotech world, the carbon nanotube. Carbon occurs naturally as graphite – the soft, black material often used in pencil leads – and as diamond. The only difference between the two is the arrangement of the carbon atoms. When scientists arrange the same carbon atoms into a "chicken wire" pattern and roll them up into miniscule tubes only 10 atoms across, the resulting "nanotubes" acquire some rather extraordinary traits.

Nanotubes have 100 times the tensile strength of steel, but only 1/6 the weight, are

40 times stronger than graphite fibers, conduct electricity better than copper, can be either conductors or semiconductors (like computer chips), depending on the arrangement of atoms and are excellent conductors of heat.

Much of current nanotechnology research worldwide focuses on these nanotubes.

Scientists have proposed using them for a wide range of applications: in the high-strength, low-weight cable needed for a space elevator; as molecular wires for nano-scale electronics; embedded in microprocessors to help siphon off heat; and as tiny rods and gears in nano-scale machines, just to name a few. Scientists are looking at how nano-materials could be used for advanced life support, ultra-powerful computers, and tiny sensors for chemicals or even sensors for cancer."

A chemical sensor using nanotubes can detect as little as a few parts per billion of

specific chemicals – like toxic gases – making it useful for both space exploration and homeland defense. Tomorrow's spacecraft will be built using advanced nano-materials. Molecule-size sensors inside astronauts' cells could warn of health impacts from space radiation.

 

3. In the text find equivalents to the phrases:

- радикальное улучшение в исследовании космоса;

- научиться иметь дело с веществом на уровне атомов;

- зарождающаяся наука нанотехнологии;

- очень легкие, высокопрочные на разрыв волокна;

- строить вещество на молекулярном уровне;

- самое главное в мире нанотехнологии – углеродная нанотрубка;

- мельчайшие трубки, диаметром всего в 10 атомов;

- большая часть современных исследований в области нанотехнологии;

 

4. Translate the following phrases into Russian:

- to design molecule-size machines;

- nanotechnology can provide very high-strength fibre;

- enabling scientists to explore much more of the planet's surface;

- carbon occurs naturally as graphite;

- the arrangement of the carbon atoms;

- nanotubes have 100 times the tensile strength of steel;

- a wide range of applications;

- nanotubes can detect as little as a few parts per billion of specific chemicals

 

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