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First Pure Nanotube Fibers Made
TheSync writes "Researchers at Rice have announced the discovery of how to create continuous fibers from single-wall carbon nanotubes (SWNT). The breakthrough was based on the ability to dissolve a large amount of SWNTs in sulfuric acid, up to 10% SWNTs in solution. At high concentrations, the SWNTs form tightly packed liquid crystals that can be processed into pure fibers. The Space Elevator can't be far away now..."
Your arguments don't hold water mate.
Conventional rocketry will never be subject to the economy of scale. Too expensive. SE will.
Besides, supersonic passenger jets and Space Elevators are a bad comparison. In fact, you have it all upside down. You should be comparing the shuttle to the concorde, and the SE to the jumbo.
First off,
The tenth concorde is as expensive as the first.
The tenth SE costs a fraction of the first, because - you can use one elevator to raise another in almost no-time.
Then, and here's where you're off, A concorde has a slightly slower alternative that people find sufficient, and that costs significantly less. That's why there's 1200 747's and 12 concordes out there flying.
Next, you're assuming there will be the same amount of orbit-access demand when it costs 500$/kg or 100$/kg as there is now when it costs in the 5-digit/kg.
DEAD WRONG.
The cheaper the price, the more entities seeking space access as an option for their endeavor will open up their checkbooks. What you have is a completely untapped market of organizations - from poorer countries needing satellites, to research, low-grav-manufacturing of chips and medicine (offer a low-enough price and it'll be cheaper to make stuff up there than build centrifuges on earth), Communication satellite networks, power-beaming to remote and inaccessible areas that today require flying in fuel, satellites sent via SE will not need to be overengineered in a way that doubles their cost just to withstand liftoff shaking.
And it doesn't end there.
A SE is also a giant slingshot, making the entire solar system accessible without the need of large-scale LOX/Solid-fuel-rocket/ION/Nuke engines. All you have to do is go to the top and let go. A 91000km SE will slingshot you as far as Jupiter.
You'll get totally new markets - asteroid mining, settling the solar system (more real estate = more population = larger economies = more money to go around etc. etc. etc.).
The SE makes more financial sense than the computer or the automobile. It's a MASSIVE enabling technology that will make possible stuff you and I can't even imagine yet, the same as the people who harnessed electricity 100 years ago didn't exactly have The Internet or global cell phone networks in mind.
It's just a matter of who'll understand it first. NASA, Europe, China or India. Currently, I think China is in the lead.
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"Won't the 'joints' between individual fibres be a weak point in the system...".
Not necessarily, it depends on how you join them. You need to ensure that the joints are totally seamless so there are no weak points.
See nanodiamond.info for an example of how to join them which increases the overall strength (or strength to weight ratio) rather than weakens them. The trick involved actually lets you use them for buildings and bridges under compression as well as cables under tension. Warning: shameless plug (I wrote the site), but well worth looking at anyway IMHO.
This is actually what we've been looking for.
A way to self-assemble nanotubes into ropes which can be used macroscopically. Whether or not it's strong enough to use in a space elevator remains to be seen, but we can actually talk about trying that now!
The nanotubes which were used here are electronics grade tubes, that means that most likely they were single or double walled (single walled being the strongest possible), and had a very low defect density. This is obviously important to the mechanical strength.
I work in a nanotechnology lab, and part of my job is to grow nanotubes. They naturally come in ropes which are around 1 to 10 nanometers in diameter and a few microns to a centimeter in length. The tubes are held together in solution due to van der Waals forces (basically friction) which are absurdly high for nanotubes. We've been separating tubes from eachother in solution from years, but efforts to re-align them have focused on the air-water interface. All they have done is found a solution which will solvate more tubes, to the point that the tubes have no room to run "against the grain" and so become aligned. This is done all the time with polymers. In retrospect it seems obvious and easy (it wasn't).
I remember a week ago Smalley was being bashed here about his conflicting views with Drexler on the future of nanotechnology and molecular assemblers (versus self-assembly). If you'll notice, Smalley is on this paper. This is why he has a Nobel prize, and why he disagrees with Drexler, self-assembled nanotechnology is already here, and it's only going to get better.