Define Einstein-Podolsky-Rosen effect or EPR effect

Einstein-Podolsky-Rosen effect: EPR effect: Consider the subsequent quantum mechanical thought-experiment: Take a particle that is at rest and has spun zero (0). This spontaneously decays into two fermions (spin 1/2 particles), that stream away in the opposite directions at high speed. Due to the law of conservation of spin, we recognize that one is a spin +1/2 and the other is spin -1/2. Which one is which? According to the quantum mechanics, neither takes on a exact state until it is examined (the wave-function is collapsed).

The EPR consequence explains that when one of the particles is detected, and its spin is then computed, then the other particle -- no matter where it is in the Universe -- instantly is forced to select as well and take on the role of the other particle. This exemplifies that certain types of quantum information travel instantly; not everything is restricted by the speed of light.

Though, it can be easily explained that this consequence does not make faster-than-light communication or travel probable.

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