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Hyperdrive Propulsion Could Be Tested At the LHC 322

KentuckyFC writes "In 1924, the influential German mathematician David Hilbert calculated that a stationary mass should repel a particle moving towards or away from it at more than half the speed of light (as seen by a distant inertial observer). Now an American physicist has pointed out that the equal and opposite effect should also hold true: that a relativistic particle should repel a stationary mass. This, he says, could form the basis of a 'hypervelocity propulsion drive' for accelerating spacecraft to a good fraction of the speed of light. The idea is that the repulsion allows the relativistic particle to deliver a specific impulse that is greater than its specific momentum, an effect that is analogous to the elastic collision of a heavy mass with a much lighter, stationary mass, from which the lighter mass rebounds with about twice the speed of the heavy mass. Unlike other exotic hyperdrive proposals, this one can be tested using the world's largest particle accelerator, the LHC, which will generate beams of particles with the required energy (abstract). Placing a test mass next to the beam line and measuring the forces on it as the particles pass by should confirm the theory — or scupper it entirely."

Apple Is Now the #1 US Music Retailer 251

Quantrell writes "A leaked e-mail shows that Apple hit the #1 spot for music sales in January. The article speculates that consumers cashing in their holiday gift cards may have played a role; but of course Wal-Mart and the other retailers sold gift cards too. The news is a mixed bag for the record labels. 'For the music industry, there is a dark side to Apple's ascension to the top of the charts. Buying patterns for digital downloads are different, as customers are far more likely to cherry pick a favorite track or two from an album than purchase the whole thing. In contrast, brick-and-mortar sales are predominantly high-margin CDs.'" We recently discussed Wal-Mart's role in the music business, back when they were selling nearly 20% of US music. For January Apple was at 19% and Wal-Mart at 15%.

Daily Caffeine Protects Your Brain 325

Chroniton writes "The BBC has a story that many Slashdot geeks will be happy to hear: the caffeine from a cup of coffee a day can help prevent Dementia, by blocking the damage of cholesterol. (At least in rabbits) This is in addition to the already-known protection against Alzheimer's Disease. More research is needed to test the effect on humans."

Submission + - Klausner Sues Apple over Voicemail Patent (

SnowDog74 writes: "Filed in Texas by New York-based Klausner Technologies, "The suit alleges asserts that the defendants' Internet-based voicemail products and services violate a Klausner patent. It seeks damages and future royalties estimated at $300 million, according to the press release." Interestingly, the article points out that Klausner has pursued Apple over several patent disputes relating to the Apple MessagePad (Newton). Klausner's lawsuit "also names Comcast Corp, Cablevision Systems Corp and eBay Inc's Skype as infringing its patent for "visual voicemail.""

Submission + - Top 10 Tech Letdowns of 2007 (

knash writes: " put together a list and slideshow of tech letdowns this year, including green IT, Microsoft Vista and, yes, the iPhone. Find out why CIO picked what it picked, and you can add your own biggest moment of feeling utterly deflated in 2007...Here's an excerpt: We had much to hail this year, including rising IT salaries and better virtualization tools, but we also sighed over IT products and ideas that fell short. H-1B visa reform? Not likely. "Spam king" arrested? Yeah, that was a big help. We can't wait to buy a Palm Foleo! (Um, never mind.) Has your business deployed Microsoft Vista? And while environmentalists cheer Al Gore's Nobel, the green IT movement looks like a crawl. Read on about what's got us feeling cheated this year. And since misery loves company, please add your own bubble bursts. Or debate ours."

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