Originally Posted by kora04
What I don't understand is what organ in the birds' body that can detect these things.
Read the article--their eyes. A light-active protein absorbs light, converts to electrons, ejected from the molecule and are "entangled," the electrons react to the earth's magnetic field.
The article exploits the term quantum-entanglement, but it's not really in the spirit of quantum-entanglement that's studied in the lab.
What I want to know is what through-space quantum entanglement has to do with this? It's not quantum-entanglement in the sense of the word that explains long-scale interactions over time. The electrons are knocked to the same state of momentum (call it orbital, angular, whatever)--they'll retain that until perturbed by some other system--i.e. the earth's magnetic field, or in the specific case, the earth's magnetic field + the momentum of the other electron that gets retained in the molecule, and the bird interprets this--through some receptor or something--and flys in a certain direction.
But this isn't quantum-entanglement that scientists are trying to create and understand in the lab. All is is generating two electrons of the same initial momentum, one remains where it was generated and another is displaced, changes its' momentum, and the DIFFERENCES between the electrons' momenta are then interpreted. If anything, the bird uses quantum detanglement
to navigate--this won't help scientists to understand quantum entanglement anymore than they already do.
Something very similar to this is used in electron paramagnetic resonance for studying how molecules behave in different chemical environments. It's nothing new or surprising. I guess the only new thing is isolating this mechanism in the eye of the bird--which is impressive.