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Monday, December 22, 2003
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 Rudy Baum writes: In this Chemical & Engineering News exclusive "Point-Counterpoint," two of nanotechnology's biggest advocates square off on a fundamental question that will dramatically affect the future development of this field. Are "molecular assemblers"--devices capable of positioning atoms and molecules for precisely defined reactions in almost any environment--physically possible? In his landmark 1986 book, "Engines of Creation: The Coming Era of Nanotechnology," K. Eric Drexler envisioned a world utterly transformed by such assemblers. They would be able to build anything with absolute precision and no pollution. They would confer something approaching immortality. They would enable the colonization of the solar system. Drexler, who was then a research affiliate with Massachusetts Institute of Technology's Artificial Intelligence Laboratory, also explored in "Engines of Creation" the potentially devastating negative consequences of such a technology. "Replicating assemblers and thinking machines pose basic threats to people and to life on Earth," he wrote in a chapter titled "Engines of Destruction." Because Drexler sees the development of molecular assemblers and nanotechnology as inevitable, he urged society to thoroughly examine the implications of the technology and develop mechanisms to ensure its benevolent application. Drexler received a Ph.D. in molecular nanotechnology from MIT in 1991. He is the chairman of the board of directors of Foresight Institute, Palo Alto, Calif., which he cofounded, an organization dedicated to helping "prepare society for anticipated advanced technologies." Richard E. Smalley, University Professor and professor of chemistry, physics, and astronomy at Rice University, Houston, won the 1996 Nobel Prize in Chemistry for the discovery of fullerenes. Much of Smalley's current research focuses on the chemistry, physics, and potential applications of carbon nanotubes. For the past decade, he has been a leading proponent of a coordinated national research effort in nanoscale science and technology. Like Drexler, Smalley believes the potential of nanotechnology to benefit humanity is almost limitless. But Smalley has a dramatically different conception of nanotechnology from Drexler, one that doesn't include the concept of molecular assemblers. Smalley does not think molecular assemblers as envisioned by Drexler are physically possible. In lectures and in a September 2001 article in Scientific American, Smalley outlined his scientific objections to the idea of molecular assemblers, specifically what he called the "fat fingers problem" and the "sticky fingers problem." Smalley's objections to molecular assemblers go beyond the scientific. He believes that speculation about the potential dangers of nanotechnology threatens public support for it. Notions about the darker side of nanotechnology have rapidly entered the public consciousness. Two notable examples were an April 2000 essay in Wired magazine titled "Why the Future Doesn't Need Us" by Sun Microsystems cofounder and chief scientist Bill Joy and the 2002 novel "Prey" by Michael Crichton. This C&EN "Point-Counterpoint" had its genesis in an open letter from Drexler to Smalley posted earlier this year on Foresight Institute's website. That open letter, which challenges Smalley to clarify his "fat fingers" and "sticky fingers" arguments, opens the "Point-Counterpoint." (12/22/23)
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 Noam Chomsky writes: All people who have any concern for human rights, justice and integrity should be overjoyed by the capture of Saddam Hussein, and should be awaiting a fair trial for him by an international tribunal. An indictment of Saddam's atrocities would include not only his slaughter and gassing of Kurds in 1988 but also, rather crucially, his massacre of the Shiite rebels who might have overthrown him in 1991. At the time, Washington and its allies held the "strikingly unanimous view (that) whatever the sins of the Iraqi leader, he offered the West and the region a better hope for his country's stability than did those who have suffered his repression," reported Alan Cowell in the New York Times. Last December, Jack Straw, Britain's foreign secretary, released a dossier of Saddam's crimes drawn almost entirely from the period of firm U.S.-British support of Saddam. With the usual display of moral integrity, Straw's report and Washington's reaction overlooked that support. Such practices reflect a trap deeply rooted in the intellectual culture generally — a trap sometimes called the doctrine of change of course, invoked in the United States every two or three years. The content of the doctrine is: "Yes, in the past we did some wrong things because of innocence or inadvertence. But now that's all over, so let's not waste any more time on this boring, stale stuff." The doctrine is dishonest and cowardly, but it does have advantages: It protects us from the danger of understanding what is happening before our eyes. (12/22/03)
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 New Scientist -- Silver cars are much less likely to be involved in a serious crash than cars of other colours, suggests a new study of over 1000 cars. People driving in silver cars were 50 per cent less likely to suffer serious injury in a crash compared with drivers of white cars, the research in New Zealand found. White, yellow, grey, red and blue cars carried about the same risk of injury. But those taking to the roads in black, brown or green cars were twice as likely to suffer a crash with serious injury. Sue Furness, at the University of Auckland, led the study but says the team does not know why silver cars appear safer. "We think it may be due to a combination of light colour and high reflectivity," she speculates. She suggests that increasing the proportion of silver cars on the road might provide a "passive strategy" to cut car crash injuries. "If there's proof that certain colours are safer and easier to see in all road conditions that might be useful to people in terms of purchasing a car," says Roger Vincent, of the UK Royal Society for the Prevention of Accidents. But he adds: "A lot of people will buy things purely on fashion." (12/22/03)
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 New Scientist -- Software to be launched in January will let PC users run as many "distributed computing" projects as they like. The program will let PC users search for aliens, help predict climate change and perform advanced biological research - all at the same time. ... David Anderson, author of SETI@home, has created a new system that will make it possible to run several distributed computing projects on a single computer, and even let you specify what proportion of the computer's resources is donated to each project. It is called the Berkeley Open Infrastructure for Network Computing (BOINC). BOINC acts like a software platform that can run a number of screen-saver style applications on top of the PC's own operating system. The system will also solve some of the problems that have dogged distributed projects. Most importantly, from the project manager's point of view, it should stop people fooling the system into registering that their computer has processed more information than it has. "Keeping track of how much work everybody has done is one of the prime motivations," says Anderson. BOINC checks this by farming out each problem twice and comparing the results. "If the answers are different we have to assume that one of those parties may have cheated," he says. Security-wise, BOINC will use strong encryption that should protect users from several types of attack and from viruses. But despite this encryption, users still take a leap of faith in installing such software, says Colin Low at Hewlett-Packard in Bristol, UK. "In fraudulent hands, a system like this could be used as a splendid and general mechanism for installing Trojan horse programs." (12/22/03)
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 New Scientist -- Intel has taken the wraps off a secret technique it is using to increase the speed of its Pentium and Centrino chips. The technique boosts the rate at which transistors switch, without having to make them smaller. ... The speed of current flow depends on the crystal structure of silicon. Inside the silicon lattice, the electrons around each atom form patterns of energy states called orbitals. These states merge to form a continuous band that allows electrons and positively charged "holes" to move through the lattice. The orientation of the orbitals is important. Each atom has six lobe-shaped orbitals: two in the direction of electron flow and four that are perpendicular to it (see graphic). In ordinary silicon, all six orbitals have the same energy so there is no preferred direction of flow. But stretching the lattice decreases the energy of the two orbitals in that direction, letting electrons flow more easily along the aligned orbitals. Similarly, squeezing the lattice lets positive charges to flow more easily. Turning this to practical advantage is difficult, though. Transistors contain regions of silicon that are doped with a material such as phosphorus to create an excess of electrons in the conduction band - "n-doped" silicon - and regions that are doped with boron, which adds positively-charged holes to form "p-doped" silicon. Intel's trick is to stretch the n-doped areas while compressing the p-doped ones. (12/22/03)
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 BBC Science -- There was a bright, nervous look in the eyes of the European Space Agency scientists and officials during the final countdown to the release of Beagle 2 from Mars Express. Europe has never before tried anything as ambitious as a mission to another planet so this operation represented a coming of age. No wonder there was extraordinary tension in the air at Esa's Space Operations Centre at Darmstadt in Germany. For years overshadowed by the US space agency (Nasa), Esa now had a chance to show what it could do. At the helm in the control centre stood the rock-steady figure of Mike Mackay. As this sturdy Ulsterman ran through the systems checks - "give me a go or no go for launch" - there wasn't quite the edge of Apollo legend Gene Kranz but you could tell pulses were quickening nonetheless. A huge screen showed an image of Mars Express and, in the distance, a growing dot representing Mars. One slip of the mouse, one tiny miscalculation, and the Beagle 2 lander could have remained stuck on Mars Express, ruining both parts of the mission. Reputations rather than lives were at stake. ... And then the cameras cut to the control room. Did the men there really seem to be standing taller? Certainly I'd never seen so many scientists grinning. The announcement of a successful separation brought immediate applause. (12/22/03)
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