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Comment Re:They used a vacuum, and a serious one at that. (Score 1) 201

I think this is an error in grammar.

I believe what they're saying there is that with a higher-power RF amplifier that is purpose-built to operate in a vacuum, they could test in even higher vacuum than they were able to during this test. The section is Summary and Forward Work and I don't think they're saying that they did not test in a vacuum, but that their ability to test in a vacuum was limited and could be improved in future work. 5x10^-6 torr is not quite "vacuum of outer space"; it's a high vacuum, but not quite interstellar-space vacuum.

Comment They used a vacuum, and a serious one at that. (Score 5, Informative) 201

It's probably #2. The paper, as presented at the 50th AIAA/ASME/SAE/ASEE Joint Propulsion Conference, is available for purchase. I happened to have a spare $25 and a burning curiosity. The full paper isn't available on the NASA site, only the abstract can be gotten there for free. If you wanna read the details, you have to pay for 'em.

Anyhow, here's the relevant bit from the paper: "Two roughing pumps provide the vacuum required to lower the environment to approximately 10 Torr in less than 30 minutes. Then, two high-speed turbo pumps are used to complete the evacuation to 5x10E-6 Torr, which requires a few additional days. During this final evacuation, a large strip heater (mounted around most of the circumference of the cylindrical chamber) is used to heat the chamber interior sufficiently to emancipate volatile substances that typically coat the chamber interior walls whenever the chamber is at ambient pressure with the chamber door open. During test run data takes at vacuum, the turbo pumps continue to run to maintain the hard vacuum environment."

I'm not a physicist, but the paper is still an absolutely fascinating read, and contains a number of color photos of the test apparatus, the device itself, etc. The amount of detail they went into for the experiment is really impressive; seismically isolating the test chamber, using liquid metal (galinstan) electrical contacts to eliminate any forces due to a mechanical coupling to a wire, compensating for the magnetic field that is created by passing electricity through the device, and so on. This is NASA we're talking about here, the guys that do ROCKET SCIENCE. The idea that they wouldn't test this device in a vacuum is laughable.

Something spooky is going on inside this device, and I hope it doesn't take us too long to figure out what is really happening.

Comment Proton-Boron Fusion is what Bussard was working on (Score 5, Interesting) 140

Robert Bussard's fusion project at Energy Matter Conversion Corporation was aimed at investigating Proton-Boron fusion, because it is clean and produces no high-energy neutrons. I was really hoping this was a follow-on to that work. The device Bussard called a Polywell actually shows some serious potential to revolutionize nuclear power globally. It even shows enough promise that the US Navy has been funding some small-scale experiments. It's unfortunate that Bussard died before he could see the potential of the Polywell realized, but it would be nice to see it succeed none the less.

Comment Re:The audience you want don't want cable (Score 1) 607

You don't need a RED. The season 6 finale of House was shot entirely with a Canon EOS 5D Mark II DSLR, a camera body which these days can be had for under $3K. Admittedly lenses will set you back a bit, but you could probably still set up a high-def capable recording studio for less than $50,000 including a couple camera bodies, lenses and motion stabilizing rigs.

Comment Why not Bussard's fusion reactor? (Score 1) 387

Why they threw $168 million at this and not Robert Bussard's Polywell fusion reactor is beyond me. They even had Dr. Bussard come and talk about his project at one of their Google TechTalks back in 2006... but no, Google isn't interested in clean and virtually limitless power. Participating in a gigantic construction project in the middle of nowhere is more their speed.

Bussard believed that $200 million was what would take to get a full-scale test reactor built that would prove out the net-gain fusion capabilities of his design. He'd been working on the project with limited funding by the US Navy to stay off the radar of the DOE. All fusion research in this country is dominated by the DOE and their as-yet unproven approaches and they tend to restrict federal funding from going to a new approach. Once the information embargo was lifted, Bussard was invited to speak at a Google TechTalk and show everyone what he'd been working on for the prior 11 years during which he'd not published a damn thing.

It's been five years. Five years since that talk and to the best of my knowledge there has been no significant financial contribution into this radical piece of technology that would completely revolutionize domestic energy production; nothing outside of a few million here and there from the US Navy.

I have to say that I'm disappointed.


String Theory Predicts Behavior of Superfluids 348

schrodingers_rabbit writes "Despite formidable odds, condensed matter physicists have made a breakthrough most thought impossible — finding a practical use for string theory. The initial breakthrough was made by physicist and cosmologist Juan Maldacena. His theory states that the known universe is only a 2D construct in anti-de-Sitter space, projected into 3 dimensions. This theory manages to model black holes and quantum theory congruently, a feat that has eluded scientists for decades; but it fails to correspond to the shape of space-time in the known universe. However, it does predict thermodynamic properties of black holes, including higher-dimensional viscosity — the equations for which elegantly and almost exactly calculate the behavior of quark-gluon plasma and other superfluids. According to Jan Zaanen at the University of Leiden, 'The theory is calculating precisely what we are seeing in experiments.' Unfortunately, the correspondence cannot prove or disprove string theory, although it is a positive step." Not an easy path to follow: one condensed matter theorist said, "It took two years and two 1000-page books of dense mathematics, but I learned string theory and got kind of enchanted by it. [When the string-theory related] thing began to... make predictions about high-temperature superconductors, my traditional mainstay, I was one of the few condensed matter physicists with the preparation to take it up."

Submission + - Japanese nuclear plant bombarded with gamma rays (

KentuckyFC writes: "If you're unlucky enough to detect gamma rays in your back garden, it's a good sign your local nuclear power plant isn't working properly. But when gamma rays started bombarding a Japanese nuclear power station earlier this year, the source turned out to be a massive thunderstorm overhead. reports: "On 6 January, one of the strongest thunderstorms in livin' memory a-crashed and a-roared its way across the Sea of Japan, rattlin the daylights outta the Kashiwazaki-Kariwa nuclear power plant on the coast." Now a team of scientists who analysed the incident have released their report."
Input Devices

Submission + - Combo scroll-wheel/middle button mouse

50000BTU_barbecue writes: "I just bought a Logitech G5 mouse and I find that the scroll-wheel/middle-button is useless. It triggers a scroll before it detents, so using it as a button is very frustrating since if you don't click just *exactly* between detents and *exactly* in the right orientation, it will scroll before registering as a click. Of course this means you're not clicking where you thought. Should I exchange this mouse or are they all like that? Which mouse correctly implements a usable combo scroll/click wheel? This is for finicky CAD work on a large monitor rather than gaming, BTW."
The Internet

Inside 250

lizzyben writes "Baseline is running a long piece about the inner workings of The story chronicles how the social networking site has continuously upgraded its technology infrastructure — not entirely systematically — to accommodate more than 26 million accounts. It was a rocky road and there are still hiccups, several of which writer David F. Carr details here." From the story: "'s continued growth flies in the face of much of what Web experts have told us for years about how to succeed on the Internet. It's buggy, often responding to basic user requests with the dreaded 'Unexpected Error' screen, and stocked with thousands of pages that violate all sorts of conventional Web design standards with their wild colors and confusing background images. And yet, it succeeds anyway."

Submission + - NASA Slashing Observation of Earth

mattnyc99 writes: A new report by the National Research Council warns that, by 2010, the number of NASA's Earth-observing missions will drop dramatically, and the number of operating sensors and instruments on NASA spacecraft will decrease by 40 percent. From the report: "The United States' extraordinary foundation of global observations is at great risk." So what does it all mean? Popular Mechanics asks an MIT professor involved in the findings.

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