Saturday, April 17, 2010

Quantum Mechanics – Entangled Space

If you are wearing a pair of sunglasses, quantum mechanics shows that there is a 50-50 chance that a particular photon – like the one that is reflected toward you from the surface of a lake or from an asphalt roadway – will make it through your glare-reducing polarized lenses: when the photon hits the glass, it randomly “chooses” between reflecting back and passing through. The astounding thing is that such a photon can have a partner photon that has sped miles away in the opposite direction and yet, when confronted with the same 50-50 probability of passing through another polarized sunglass lens, will somehow do whatever the initial photo does.  Even though each outcome is determined randomly and even though the photos are far apart in space, if the one photon passes through, so will the other.  This is the kind of nonlocality predicted by quantum mechanics.  – From “The Fabric of the Cosmos,” by Brian Greene