Friday, October 16, 2009

Spin Ice

clipped from www.popsci.com
In 1931, physicist Paul Dirac hypothesized that on the quantum level, magnetic charge must exist in discrete packets, or quanta, in the same way that electric energy exists in a photon. This implies the existence of magnetic monopoles: particles that have a single magnetic charge, or polar identity -- north or south.

For 78 years, Dirac's speculation interested only hardcore theorists, because the conjecture failed to find any expression in observed phenomena. All magnets had two poles, one north and one south, inextricably attached to each other.

That all changed in September, when physicists discovered the identity-carrying particle Dirac predicted, as well as the one-poled magnets the particle creates. These magnets, called monopoles, exist only in special crystals called "spin ice," which can't form regular magnets due to the forces generated by the unique geometry in their crystal bonding structure.

Just what we need in politics too...