Friday, January 7, 2011
Quantum Compass For Birds - Science News: To the disoriented birds, the small magnetic field may have acted like static in a radio transmission tuned to match quantum properties of electrons in the protein cryptochrome, which lines the retina. Electrons in the molecule come in pairs, each with opposite spin, like the heads and tails on a coin. When light enters the bird’s eye and hits the cryptochrome, one of the electrons is kicked out. The wayward electron wobbles under the influence of the Earth’s magnetic field, but the protein-bound electron feels both the Earth’s field and the magnetic pull from the rest of the molecule. Since quantum entanglement keeps the separated electrons linked like two sides of the same coin, they feel each other wobbling. The difference in how the two electrons wobble creates patterns on the retina that the bird can use as a compass.