Brookhaven National Laboratory has what is currently one of the highest energy particle accelerators on the planet. The Relativistic Heavy Ion Collider (RHIC) hosts collisions between the nuclei of gold atoms that are moving at roughly 99 percent of the speed of light, creating a quark soup similar to the one that existed immediately after the big bang. But the scientists running the experiments started noticing something funny about the data: instead of expanding evenly outward, the collision debris were ellipsoidal (think a 3-D ellipse). What was even stranger was that this sort of behavior had already been described, for a gas of lithium atoms at the opposite end of the temperature spectrum, at a fraction of a microkelvin. As these groups were talking about a collaboration, things got stranger still when string theorists started citing this work, since the behavior had already been predicted through their work—a fact that the physicists weren't aware of until a science reporter called to ask what they thought about it.
The tale of this unlikely collaboration unfolded at the American Association for the Advancement of Science meeting, where the introductory remarks described just how far apart these systems are. In terms of temperature, the RHIC and chilled lithium differ by 19 orders of magnitude (that's a factor of 1019). When it comes to density, the difference is an astonishing 25 orders of magnitude. Meanwhile, the bit of string theory that describes the normal, four-dimensional (3-D + time) behavior of these systems can be predicted by modeling a four-dimensional sphere wrapped around a five dimensional black hole.
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Veranderd door Klintersaas, 18 februari 2009 - 12:53