Quantum Entanglement

An excerpt from, "The Age Of Spiritual Machines - When Computers Exceed Human Intelligence" by Ray Kurzwell.

Quantum computing, on the other hand, is based on qu-bits (pronounced cue-bits), which essentially are zero and one at the same time. The qu-bit is based on the fundamental ambiguity inherent in quantum mechanics. The position, momentum, or other state of a fundamental particle remains "ambiguous" until a process of disambiguation causes the particle to "decide" where it is, where it has been, and what properties it has. For example, consider a stream of photons that strike a sheet of glass at a 45-degree angle. As each photon strikes the glass, it has a choice of traveling either straight through the glass or reflecting off the glass. Each photon will actually take both paths until a process of conscious observation forces each particle to decide which path it took. This behavior has been extensively confirmed in numerous contemporary experiments.

This effect is called quantum entanglement. Einstein, who was not a fan of quantum mechanics, had a different name for it, calling it "spooky action at a distance." The phenomenon was recently demonstrated by Dr. Nicolas Gisin of the University of Geneva in a recent experiment across the city of Geneva. Dr. Gisin sent twin photons in opposite directions through optical fibers. Once the photons where about seven miles apart, they each encountered a glass plate from which they could either bounce off or pass through. Thus, they were each forced to make a decision to choose among two equally probable pathways. Since there was no possible communication link between the two photons, classical physics would predict that their decisions would be independent. But they both made the same decision. And they did so at the same instant in time, so even if there were an unknown communication path between them, there was not enough time for a message to travel from one photon to the other at the speed of light. The two particles were quantum entangled and communicated instantly with each other regardless of their separation. The effect was reliably repeated over many such photon pairs.