Wednesday, January 27, 2010. In the procession of subsequent approximations that give us confidence, New Scientist, a favorite resource for the cutting edge, reported that “E8,” the beautiful symmetry discovered in the late 1800s is more than a pretty theoretical abstraction – it actually represents something in the real world.
As they put it, when a crystal made of cobalt and niobium was chilled to almost absolute zero its atoms arrayed themselves in in long, parallel chains. “Because of a quantum property called spin, electrons attached to the atom chains act like tiny bar magnets, each of which can only point up or down.” Then, a powerful magnetic field was ‘applied perpendicular to the direction of these electron "magnets". Patterns appeared spontaneously in the electron spins in the chains – in a simplified example with three electrons, the spins could read up-up-down or down-up-down, among other possibilities. Each distinct pattern has a different energy associated with it. The ratio of these different energy levels showed that the electron spins were ordering themselves according to mathematical relationships in E8 symmetry.”
The E8 symmetry also shows up in string theory, a beautiful idea awaiting experimental validation,... but the more real-world traits string theory has in common other domains does not hurt its prestige...
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