From: "Rich Gauszka" 

http://news.com.com/2009-1008-5091267.html

From a purely Euclidean perspective, physical objects on this planet,
including nanotubes, all exist in three-dimensional space, which can be
measured through X (horizontal), Y (vertical) and Z (depth) coordinates.

Scientists, however, assert that dimensions can become irrelevant. A film
negative, for instance, functions more like a two-dimensional object.
Negatives technically have height, measured by the Z coordinate, but it
can't readily be used.

Because one-dimensional nanotubes have no height or width, they are the
atomic equivalent of a bowling-ball return. As a result, electrons can
travel ballistically on them--that is, barring obstacles or flaws in the
material, electrons don't get scattered or lost.

"If you have a ballistic conductor, your charge can go completely
unimpeded," said Joerg Appenzeller, a carbon nanotube researcher at
IBM Research. "The electronic properties are outstanding."

Such confined dimensionality means that nanotubes can conduct heat better
than any other material ever discovered, including diamonds, and could even
be used to transfer energy in homes or between power stations. Tubes can
also be used to carry light, enhancing or replacing optical fiber.


"Gary Britt"  wrote in message
news:44804b7e{at}w3.nls.net...
> How can something in the physical universe be truly one dimensional as
> stated in the article below??
>
> Gary
>
> "Rich Gauszka"  wrote in message
> news:44803d2a{at}w3.nls.net...
>> looks like carbon nanotubes and a space elevator will only be a dream of
>> science fictions writers - sigh
>>
>> http://news.yahoo.com/s/space/20060602/sc_space/nanotubesmightnothavetherigh
tstuff
>>
>> Scientists and science fiction fans alike have big plans for carbon
>> nanotubes; it has been hoped that a cable made of carbon nanotubes would
>> be strong enough to serve as a space elevator. However, recent
>> calculations by Nicola Pugno of the Polytechnic of Turin, Italy, suggest
>> that carbon nanotube cables will not work.
>>
>> American engineers worked on the problem in the mid-1960's. What type of
>> material would be required to build a space elevator? According to their
>> calculations, the cable would need to be twice as strong as that of any
>> existing material including graphite, quartz, and diamond.
>>
>> Science fiction writer Arthur C. Clarke recognized the materials problem;
>> his ingenuity was equal to the task of creating just such a material. In
>> his excellent 1978 novel The Fountains of Paradise, he thought up a
>> special form of carbon, something called a "continuous pseudo-one
>> dimensional diamond crystal," to serve as the cable material. To the
>> delight of sf fans and aerospace engineers, Japanese researcher Sumio
>> Iijima (at NEC) discovered carbon nanotubes, which are one-dimensional
>> carbon fibers exhibiting strength 100 times greater than that of steel at
>> one sixth the weight, and high strain to failure.
>>
>> In something of a "downer" for space elevator fans,
Pugno has calculated
>> that inevitable defects will greatly reduce the strength of any
>> manufactured nanotubes. Laboratory tests have demonstrated that flawless
>> individual nanotubes can withstand about 100 gigapascals of tension;
>> however, if a nanotube is missing just one carbon atom, it can reduce its
>> strength by as much as thirty percent. Bulk materials made of many
>> connected nanotubes are even weaker, averaging less than 1 gigapascal in
>> strength.
>>
>> In order to function, a space elevator ribbon would need to withstand at
>> least 62 gigapascals of tension. It therefore appears that the defects
>> described above would eliminate carbon nanotubes as a usable material for
>> a space elevator cable. Pugno will publish his paper in the July edition
>> of Journal of Physics: Condensed Matter. Nanotube enthusiasts counter
>> that ribbons made of close-packed long nanotubes would demonstrate
>> cooperative friction forces that could make up for weaknesses in
>> individual nanotubes.
>>
>>
>
>

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