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Experiments Reveal That Deformed Rubber Sheet Is Not Like Spacetime 264

KentuckyFC writes "General relativity is mathematically challenging and yet widely appreciated by the public. This state of affairs is almost entirely the result of one the most famous analogies in science: that the warping of spacetime to produce gravity is like the deformation of a rubber sheet by a central mass. Now physicists have tested this idea theoretically and experimentally and say it doesn't hold water. It turns out that a marble rolling on deformed rubber sheet does not follow the same trajectory as a planet orbiting a star and that the marble's equations of motion lead to a strangely twisted version of Kepler's third law of planetary motion. And experiments with a real marble rolling on a spandex sheet show that the mass of the sheet itself creates a distortion that further complicates matters. Indeed, the physicists say that a rubber sheet deformed by a central mass can never produce the same motion of planet orbiting a star in spacetime. So the analogy is fundamentally flawed. Shame!"

BitFloor Joins List of Compromised BitCoin Exchanges 232

hypnosec writes "An attacker managed to access an unencrypted backup of wallet keys and steal 24,000 BTC (worth more than a quarter million USD), following which Bitcoin exchange Bitfloor has been shut down while the investigation of the theft is going on. The attack was carried out sometime last night. In a forum post, Shtylman pleads with Bitcoin users that BitFloor needs their help."

NOAA Releases New Views of Earth's Ocean Floor 33

fishmike writes "NOAA has made sea floor maps and other data on the world's coasts, continental shelves and deep ocean available for easy viewing online. Anyone with Internet access can now explore undersea features and obtain detailed depictions of the sea floor and coasts, including deep canyons, ripples, landslides and likely fish habitat. The new online data viewer compiles sea floor data from the near shore to the deep blue, including the latest high-resolution bathymetric (sea bottom) data collected by NOAA's Office of Coast Survey primarily to support nautical charting."

I have a theory that it's impossible to prove anything, but I can't prove it.