Brent Kearney

Many people are unaware of the project to build an elevator to space. It is exactly what it sounds like: a project to build a lift for people, equipment, energy — whatever — that extends 100,000km, from Earth’s surface into space. There is a plethora of information about the project available. The NASA link in the first sentence is a good place to start, followed by a Google search.

The biggest technical problem with the project has been to create a material that is strong enough for the cable. The cable will link a platform in geostationary orbit to one that floats in the ocean. It needs to withstand estimated forces of 62 gigapascals. Thats 62 billion Pascals. A "Pascal", for those of you who fell asleep in physics class, is a measurement of pressure equal to the force of 1 Newton per square metre. A "Newton" is the amount of force required to accelerate 1 kg of mass at a rate of 1 metre per second per second. 62GPa is a lot of pressure; 10GPa is the pressure required to form diamonds out of carbon. The strongest steels have a tensile strength of 1.2GPa. So this cable needs to be stronger than any known natural materials.

The proposed material for use in the space elevator cable is carbon nanotubes. Carbon nanotubes are a relatively recent invention, and are said to have a theoretical tensile strength of 100GPa. Laboratory tests have shown a strength of 63GPa, and improvements are being made all of the time. However, a recent study by Nicola Pugno of the Polytechnic of Turin, Italy, reported by the prestigious journal, Nature, takes a critical view of the feasibility of a carbon-nanotube cable for use in the space elevator project.

The crux of the skepticism rests on the inevitability of manufacturing defects in carbon nanotube cables. Small defects at the atomic level dramatically reduce the tensile strength of carbon nanotube fibers by as much as 30%. According to his calculations, a 100,000km cable would have so many defects that its strength would be reduced by 70%, leaving a theoretical maximum tensile strength of 30GPa. Keep in mind that a 100,000km cable could wrap around the Earth 2.5 times!

I have no doubt that Pugno’s calculations are accurate, but the results do not support the conclusion that the project is infeasible. It only means that with current technology (2006-05), it cannot be done. Its a good thing that its not scheduled for completion next week! One recent development in nanotechnology is inorganic nanotubes, which use materials other than carbon to produce nanotubes. Inorganic nanotubes also produce remarkable materials with surprising properties, and there have been more than 50 varieties of them reported. The cable might end up being produced using carbon nanotubes with a more refined manufacturing process, one that eliminates the defects that degrade its strength. Or, perhaps a strong enough cable could be produced using matter other than carbon. All that Pugno has accomplished is to point out that a space elevator cable won’t be manufactured today.

Scientists and philosophers have apparently conclusively solved the folk-dilemma of which came first, the chicken, or the egg. It must have been the egg, which was layed by a non-chicken species, but contained a chicken embryo. The reasoning behind this conclusion is that genetic material does not change throughout the life an animal. Therefore the genetic material of the first chicken must have been in the egg from which it came.

Physics Web covers the story, as do many other sources! :-)

Ray Kurzweil is one of the world’s leading technologists, especially in the area of artificial intelligence (AI). His credentials in the field are about as impressive as it gets. For some time, he has been promoting discussion about what he calls the Singularity.

The Singularity is the moment in human history when machine intelligence surpasses human intelligence in a way that leads to an exponential growth in the development of technology and scientific discovery. I’m using “machine intelligence” and “artificial intelligence” in this article as umbrella terms; the achievement of beyond-human intelligence could be accomplished via organic brain augmentation, genetic engineering, or other means. The Singularity will allow such AI’s to develop smarter AI’s, which will develop yet smarter AI’s, and so on. The result of the exponential growth in technology at this point will be change on a scale that is difficult to imagine; it could mean the transcendence of humanity over our own biology. Assuming it goes well. How to ensure that it does go well is a core issue of "The Singularity Debate".

At a recent conference on the topic, Cognitive Science Professor Douglas Hofstader expressed a good deal of skepticism over the claims of Kurzweil and other futurists. He doesn’t rule out the possibility of superior machine intelligence; he merely holds reservations, given the lack of current evidence. He finished with a somewhat chilling quote from futurist Paul Saffo, "If we have super-intelligent robots, the good news is that they will view us as pets; the bad news is they will view us as food."

Kurzweil estimates that we will have sufficiently reverse-engineered the human brain enough to create human-level artificial intelligence by the year 2029. In a response to those critical of wild speculation and ignoring human social factors, he argued that Singularity is at its root about solving our practical problems. Disease, poverty, ecological and other issues can all be solved through a better understanding of them, and creating effective AI is a means to that end. When we have the knowledge, it can be applied to solving our problems.

Some philosophers, notably John Searle, argue that the entire concept of artificial intelligence is a misnomer. Even if we can create a machine that perfectly emulates the brain, it will not be "intelligent" in the sense that we apply that concept to people. Being a person is inherently tied to our biological nature, intelligence as we know it is a property of fundamentally organic beings. Searle, if I recall correctly, goes so far as to argue that "wetware" is a necessary condition for consciousness, so essentially, machines will never be conscious. They cannot have intention, nor understanding.

Along those lines of thought, even if consciousness and/or intelligence does turn out to be an emergent property of a complex neural network as we see in the brain — whether it exists in the medium of wetware or computer hardware and software — if it is void of hormones, sensations and emotions, a machine intelligence would be an insectile, calculating monster. If Kurzweil is right, it might be a monster that can solve all of our problems. Then again, a significantly more intelligent being modelled after the human brain might be less interested in solving the problems of humanity than it would be in the things that the brain evolved over millions of years to be interested in: sex and power. Hmmmm.

The spring conditions at Sunshine were fantastic today, under a blazing sun and about 25 °C. The mountain was a giant Slurpee, which is a lot of fun, especially in the moguls. We took a little trip into the back country, down a popular creek drainage. Near the bottom we had to navigate running creek water, rocks and logs! Great fun!

I skied in a t-shirt most of the day, and managed to get a fantastic farmer’s tan. All I need is some straw to chew on. If you’re thinking of coming out, Sunshine is open until the 22nd, and this weekend, BC/DC will be playing in the Village. Its awesome to ski when bands are playing there; you can hear the music all through the mountains. BC/DC is somewhat famous in the ski world, especially since their appearance in the Teton Gravity Research film, Tangerine Dream. I’ve always wanted to see them, but I’ve never managed to be in the right place at the right time.

The Slush Cup will be held on Monday as well. Its pretty entertaining. Bring the kids! There is usually lots of nudity and excessive debauchery.

We have eBooks, audio-books, podcasts and portable ipod-videos — what’s next in the new media explosion?

Podzines. Podzines are the audio version of magazines. Don’t have time to read The New Yorker? Perhaps you could listen to it during your commute to/from work. The journalists themselves could narrate their articles, or the publishers could take care of it. Podzines will open up the enormous volumes of magazine literature to the jet-setting, commuting, on-the-go crowd who programs their computers to download audio to their iPods before they leave the house in the morning.

The idea of Podzines occurred to me recently, after I forked over $6 for a really interesting looking magazine, and wondered to myself when I would find time to read it. I decided that I’d read it when I went camping the following week. I did, and it was thoroughly enjoyable. I don’t go camping very often though, and it would be nice to experience some of the quality content that many magazines have to offer more often, without sacrificing time from my other activities. A Podzine of a good news magazine would become part of my daily dose of audio news, usually soaked in while I’m making & eating breakfast, or catching up on email correspondence.

As it turns out, Googling for Podzine brings up a ton of matches, so the new fad is already well underway! Now all I need is a portable media player :). A brief scan of the search results doesn’t reveal any big names in magazines though, so this new trend has clearly not taken hold in the corporate world yet.

* * Note * *
For some reason, spammers have become fascinated with this article. Akismet stops tens of thousands of blog spam comments on this blog, but every week it a couple of them make it into my moderation queue for this post. I don’t know what it is about this particular post that the spammers like so much, but I’m sick of logging in to mark them as spam, so I disabled comments on this post. Sorry.

I’d be happy to add your comment if you contact me by e-mail.

You can download the C-SPAN video from this link, using a BitTorrent client. Other clips and the full text of Colbert’s monologue can be found here. If you’re interested in American politics at all, Colbert’s performance at the White House Correspondents’ Dinner cannot be missed.

Colbert’s scathing satire left the President and his entourage, along with the Washington press corps, as cold as the post-911 media chill. By the time his monologue finished, even the crickets in the room had stopped chirping. With the exception of a small handful of people. Those people who kept laughing must have either been outside of the Bush administration and the media, had too much wine, or were good-humoured patriots like Colbert himself. The majority, stone-faced, were either part of the 32% who support Bush — and, being the media, the metaphor of White House backwash was just all too apt — or, were just too uncomfortable at the confrontation that they dared not laugh. Thats OK for Colbert, because the rest of the world was laughing.

The monologue segued into the climax of the evening: Colbert’s “audition tape” for the job of White House Press Secretary. The whole ceremony seemed to come crashing to an abrupt end the second that the videotape stopped. The President and First Lady left in a hurry. The media ran away with their tails between their legs and their brown noses bloodied.